It may have been pertinent to point out that the Axial Tilt varies between 22.1 degrees and 24.5 degrees, the cycle is around 40,000 years, and that our seasons are drastically affected over time by the change. This change in tilt play a role in Milankovitch Cycles and, so it is theorized, the ebb and flow of ice ages. We are in an inter glacial period now.
and right now we are closest to the sun during S Hemisphere Summers and futher away during their winters. You would expect s hemishere would have more extreme seasons but they don't because there is much more water and less land than N Hem which heats and cools slower. But all those orbital factors change over time and of couse there is continental drift. A lot of stuff going.
Yes, great point. The Milankovitch cycles include the elliptical orbital cycle of about 100,000 years, and also recession of the earths axis (tilt) so in 13,000 years summer in N hemisphere will occur in January (26,000 year cycle). So what will be the outcome of summer in NH coinciding with being closest point in orbit to the sun? I assume we’ll be deep in an Ice age for the reasons you mention (waters specific heat capacity), but unfortunately I won’t be around to find out.
There are so many random factors that allowed life on Earth (e.g., magnetosphere, big satellite moon, Goldilocks Zone) that it comes as no surprise how rare life is in our galaxy.
You could be right, Anything is possible. Given the vastness of not only space but also time, it would be a remarkable coincidence to detect a signal in the short time that humans have been listening.@@Abmotsad
Interesting video, as always Alvin, but with many speculations. We used to say too that we, humans, exist thanks to the meteor that kill the dinosaurs. What grows in winter could grow in the regions that will have cold weather. There are solutions to the "new" problems you presented. Anyway, you always present a case that make us think as scientist, and this is what I like the most! Thank you so much for that!!!
I'm not going be a backseat driver. Thank you for the video, it was thought provoking. I especially like how you present the material, its easy to understand and digest. Keep up the good work.
Your part concerning snowball earth - would the effect not depend upon how much free water was available to create snow/ice? And consider that evaporating the oceans to a major extent would lead to a very salty - and thus possibly unfreezable - liquid.
Small issue: The implication that without the Moon we wouldnt have a tilt. The opposite could be true, that without the Moon stabilising the Earths axial tilt, the tilt would swing wildly around (Well, wildly on geological time scales.) This would also produce a whole host of problems not only making life different, but much more difficult. Im not sure how well proven the stabilising influence is, but assuming it is the case to produce the effects in the video youd somehow need to capture a big moon or otherwise stabilise the Earth without our being knocked over at all in the process.
@@ArvinAsh I wouldnt have thought the nature of planet formation as we understand it would be inclined to produce a perfectly vertical align planet that can remain stable by chance. This seems to be born out by the other planets with their wildly differing tilts and Mars which has been investigated in great detail and is understood to have swung by 10 degrees in just the last million years. Though I dont know all the mechanics involved.
@jk0621 Yes, it does. It is quite possible that Mars too was similarly hit with a large celestial body but ended up absorbing it over time, such that it did not form a large satellite.
According to recent estimates, axial tilts do not vary as much without a moon as previously thought. Originally, it was thought to be 20+ degrees, now its thought to be 5-10 degrees at most for a planet as large as earth, coupled with the fact there is a large gas giant only 4 AU more distant from the sun that banks on the eqrth (Jupiter is thought to be the main cause of the milankovitch cycles, with Venus being less so).
Growing up in Canada where we have long nights in the winter and long days in the summer, it was not a difficult concept to understand since we experience it directly. Explaining this to my friends who move here from tropical countries takes some effort. I have been to the far north when the sun was high in the sky at 2 AM. Really messed with my sleep.
Coal was mined and used to a small extent during Roman times and possibly before that, what happened in the 18th and 19th centauries was it was mined in ever greater quantities probably due to wood becoming scarcer in places like England due to increased ship and house building so less for fuel.
Hi Arvin, for a spherical earth when we say that it is tilted, what does it specifically mean A. Is the actual "North Pole" or northern most point on earth not at top of the sphere but shifted out 23 degrees B. Axis along which spin takes place is tilted but "North pole" is still at top of sphere C. Both North Pole and magnetic North Pole coincide with axis and are not at top of sphere Your insight will really put things in perspective for me. Thanks
With no tilt I would have to believe that the weather extremes would be much greater as both heat and cold areas would be more concentrated creating much stronger mixing layers.
I've always wondered if a locked planet, eg Mercury, with a super hot face and freezing cold rear face, has a goldilocks zone at the interface, and how thick that zone would be.
With no Moon to stabilize it's tilt, Earth's rotation would become unstable, wobbly, and prevent any consistent weather pattern over a long enough time to permit the evolution of life.
Without axis lilt there would be only one spring season..after third world war..i.e, after dropping nukes at North pole and South pole earth axis would be zero degree lilt. This will happen in 2036. Then after 2500 years due to natural calamities the earth axis tilts by 23.5degrees. This world drama cycle repeats every 5000 years identically second by second. What ever is happening has happened a cycle ago.
Besides haveing a 23.5 degree tilt, Earth's axis also wobbles like a top. Wobbles anywhere from 22.5 to 24.5 degrees. More upright the axis, ice age, more tilted, global warming.
Thank you for developing this topic. I thought that the lack of axial tilt would lead to constantly raging strong storms due to the difference between equatorial and polar temperatures. Was I wrong about this? :)
Pretty sure the lack of tilt would lead to stratification, & thus the atmosphere would be relatively calm, with no "trade winds" or ocean conveyor belt cycles. So there would be less opportunity for storms. The seasons cause the atmosphere to mix & move around (trade winids, oceanic conveyor belts), generating storms.
@@merion297 You need something to mix the areas together, such as axial tilt does. Picture a blender in which the ingredients for a Margarita have been dumped into, but the blender isn't plugged in. Very little mixing will occur. Sure, the elliptical orbit of the Earth, various tectonic forces, & the gravitational tug of the moon might provide some energy, but possibly not enough to overcome atmospheric "drag". This would be an interesting scenario to model, such as they are doing to forecast the effects of climate change, but the computing power to do so is beyond the reach of armchair speculators such as us.
Just basic logic but it would far more likely that things would move in a different pattern than come to a standstill. The 'blender' (the sun) is always plugged in. Even if always the highest over the equator the difference in more water being evaporated here would surely lead to movement around the earth. @@sideshowbob
@@barleyeducated8714 Well it's like predicting the results of human induced climate change. The Earth's climate is such a complicated system, with so many variables, even our best computer modeling attempts are still primitive & not definitive. This would be the same. More fun for us to randomly speculate lol.
I don't agree. That's a pretty tough "what if..." to figure out. There are no seasons within a few degrees of the equator and that's probably where humans started out. It's hard to judge what edible plants would be around because the plants we have now evolved with the seasons. Half the plants on earth now evolved in the equatorial zones with no seasons, (... life finds a way"). It doesn't take much science or imagination to see plants evolving in the cooler regions. Humans would settle in the comfortable regions. As far as innovation, we can only guess. People living in that world would think living someplace where the temperature swings by a 100° would be hellish. I think living in a world where you could migrate to your comfort zone and not have seasonal changes would be very peaceful.
Life is a mathematical impossibility unless someone created it in a perfectly designed setting. More than 2,000 variables have to line up just for life to be possible on a planet. Life would also be impossible were it not for our perfectly placed moon causing tides.
Variation in the tilt probably causes ice ages but albedo is not the only possible positive feedback. An asymmetric buildup of ice would shift the moment of inertia not to mention groundwater distribution. So cause and effect is not so straight forward. A simplistic correlation of tilt with ice ages has its problems. Not to mention variations in sun luminosity.
Our seasons would be much longer and hotter/colder. An example of this is the planet Uranus which is orbiting the Sun tilted at 82.23º, as if it was rolling. Winter at the poles last 42 years each during its 84 year orbit around the Sun. (Its poles receive more energy when they face the Sun but for unknown reasons the equator remains warmer.)
@@JohnnyAngel8 Maybe because its equator still receives sun light the entire year while each of the poles have chance to shed its heat for half year at a time.
more intense season, tropical temperature at summer in pole area and it going to snow in tropical area at sea level, even equator may see snow at sea level at summer and winter solstice
I get the feeling (just a quick thought), that not having an axial tilt would be conductive to aquatic lifeforms to develop more efficiently than terrestrial ones, since water acts as a safer, denser medium than air and it also offers some padding and intermixing of temperatures between latitudes due to currents maybe?
That's why we have astronomical and meteorological winters. The first is in reference to astronomical points in the Solar System; the second is in reference to the three coldest months of the year. Our calendars only list the astronomical moments. I do think that calendars should show "solstice" and "equinox" rather than "winter begins" and "autumn begins". Maybe some do but I haven't seen any.
As the Earth's temperature changes lag behind changes in the amount of sunlight received, it makes some sense to start seasons with the solstice or equinox. When I moved from the US to Australia 30+ years ago I found it strange to arbitrarily tag seasons by the calendar - first day of Summer is Dec. 1st, first day of Autumn is Mar. 1st, etc. In reality "seasons" are just convenient divisions around the solstice and equinox, and we can tag them however is convenient. Why not eight? Or two? Many tropical areas have a hot, a wet, and a dry season. That works for them.
Our solar system is a true work of art. The relationship between the sun, moon and earth is so amazing. It's almost like a matter of sheer coincidence, especially when it comes to the seasons and the lunar eclipse. The coincidence behind the distances between the sun, moon and earth is mind blowing. As I say, a true work of art. As if it were designed to be that way. Good thing too. Just look at our existence, and how animals and other forms of life thrive in their natural state.
There are many who say the same! I feel it as well! In 2012 the transformation started and it ends in 2030. Hence the Orwellian UN Agenda 21/30, World Economic Forum "Own Nothing and Be Happy!" by 2030.
4:11 why you don't specify that you're talking about the Northern Hemisphere. Since it's the opposite season in the Southern Hemisphere. So it's not ironic that Northern Hemisphere Winter is when we are closest to the Sun, since it is also the Southern Hemisphere Summer.
Just like he said, because the main contributor to seasonal temperature variation is earths tilt and not it’s distance from the sun. Saying that it’s summer in the southern hemisphere when the earth is closer to the sun confuses that point.
In 1437 grandson of Timur the Great Ulugbeg measured Earth axial tilt as 23.5047 or 23 degrees 30 minutes and 17 seconds by his quadrant in Samarkand observatory. In 2022 Earth tilt was about 23.4365 degrees. Difference in 585 years was about .0682 degrees, it makes 0.1166 degrees of changing of tilt for millennium. Tilt of Earth currently s being reduced until reaching a minimum value of 22.1 Degrees. Maximum axial tilt of Earth in 24.5 degrees was in 7068 BC in the last cycle.
With the ice caps building in depth the ocean levels would fall revealing more and more land surface. As temperatures fell hot arid regions would become livable and able to sustain crops. So maybe it would not become a 'problem' for tens of thousands of years if at all.
Question re the shortest day: the day with the earliest sunset is December 7. After that, the afternoons get a bit brighter later. The day with the latest sunrise is January 7; after that, the mornings get brighter earlier. What causes this? The 'shortest day' is actually the day midway between these two dates.
I've thought about this myself, but have never read anywhere as to why this is. So, I tried to come up with an explanation on my own. I suspect it may be due to the affects of the sidereal day. This is where the earth actually has to rotate 366.25 times a year in order to produce 365.25 days. It therefore also needs to rotate relative to a fixed point in space about four minutes faster than the 24hrs/rotation we experience in terms of day/night. If you could imagine for a moment a situation where the earth was "frozen in place" rotation-wise (meaning it didn't rotate at all), but still revolved around the sun normally, you would come to see that for each year, you would in fact have one full day - albeit a day that would take a full year, not 24 hours. With this day though, the sun would slowly rise in the WEST, and eventually set in the EAST about six months later. It would be a sort of long "backwards" day. In order to overcome it, and produce the 365.25 days we experience, you need the 366.25 rotations, which requires a touch more speed. As to what this has to do with the earliest and latest sunrises and sunsets being offset from their respective solstices, is that the reverse effects of the sidereal day is overcoming the very slow changes in sunrise and sunset that occur just before and soon after the solstice. If you consider this like a bell curve where the change in the length of the day approaches zero and then begins to reverse at the crest and trough of the curve, at those points the effect of the sidereal day is able to overtake the regular effects of the changing length of day since it is either approaching or slowly moving away from zero. It's sort of like in December the sun is setting earlier and earlier, but it is doing this ever more slowly, because things are soon about to reverse. The sun would keep setting earlier until the solstice in the second and third week of December, but the earth revolving around the sun is now having a greater effect on the day. The sidereal "backwards day" whose small effect is now relatively stronger, is able to kick it in the other direction a couple of weeks before you would normally expect the reversal. The sunrise meanwhile is occurring later at a greater rate than the sunset is happening later, but this changes at the solstice where the later sunset overtakes the later sunrise, which itself will not reverse for another couple of weeks - about the beginning of the second week in January. The two reversals are about a month apart, and again I think the effects of the sidereal day account for all this. Does any of this make sense? I perhaps haven't explained my suspicions effectively, or I'm simply incorrect. I sit around and sometimes speculate about things I've noticed but have been unable to really look up. The sidereal day thing I was able to look up a while back, after it struck me that you needed 366.25 rotations because of this "backwards day" that's created by going around the sun. I suppose that I could try typing in "solstice sunset/sunrise offset" or something like that to figure this out, but I have frankly begun hitting the Heineken's a bit early today and I barely was able to write out this mishmash. Anyway, cheers!
The minute I saw the title, I was reminded of Immanuel Velikovsky’s ‘Worlds In Collision,’ where he imaginatively describes where the North Pole was depicted as being cantered on the Boothia Peninsula, where the earth’s tilt was changed from where it was then, to where it is now, changing the temperature of areas in Siberia so much, that animals literally froze. All kinds of ice age species have been discovered in Siberia tens of thousands of years old almost perfectly preserved, while on the other side of the earth, whole areas of the northern part of the North American continent were suddenly made liveable.
Cool dude , there has to be a reason how a wooly mammoth freezes with undigested food in its stomach huh ? No one even contemplates this dynamic but you do 😊
@@rogerwolfe1888 Yes, I was quite fascinated with the explanation, though the probable causes of drastic climactic changes are perhaps due to much less dramatic swings than the earth shifting on its axis to that extent. A dramatic climate change occurred in 536 AD, due to a volcanic eruption which had been recorded in tree rings and ice cores, so if there were a volcanic eruption in the era of 40,000 years ago, this could be the cause. If there were a shift recorded in recent geologic timescale, there would be some evidence in the cores of drill samples in the oldest glaciers. Velikovsky’s imaginary prognostications set out from times without a real geological scale of events. The curious outcome of catastrophism would be that the ‘end of the world’ has already occurred.
@@effingsix3825 Do you have any thoughts on crustal displacement theory ? It is hard to prove but Einstein was very curious on the subject and we know the continents have gradually shifted over great periods of time but dramatic shifts of the earth crust is not usually accepted ! However some geological research does show that not all uplifts and geomorphology are slow but could be dynamic movements ! Any way I’m just an amateur who likes to think about such matters ! Have a nice day
@@rogerwolfe1888 I suppose that the earth’s mantle is a matter for geologists(good article in Wikipedia), though I really like the idea that the earth was once much smaller in size and literally grew, which separated the continents. There’s no evidence this is correct, except that the continents fit together quite curiously should the earth have been smaller at one time. I like the Electric Universe’s theory that earth was once a satellite of Saturn, which was at one time a brown or red dwarf that was captured by the Sun. This explains why the earth’s tilt is the same as other planets, which were once satellites to Saturn before capture. Other planets don’t have the same tilt. The solar system is quite unique in that it has smaller planets in the inner orbits, while gas giants such as Saturn, Jupiter, Neptune and Uranus are at the outer part of the system, quite the reverse wha5 is found in astronomy.
@@effingsix3825 that is fascinating and even in some ancient mythology Saturn plays a dominant role in how they view their creation ! Your probably very close to the truth because the migration of continents from Pangea makes more sense when you expand , it seems more natural and I’ve always wondered how the continents could migrate ? Thanks
Earth , Mars and Saturn all have about the same tilt. Doesn't the theory of how earth got it's tilt from a planetary collision then mean that these other planets also had the same type of collision, and isn't that just bit too unlikely to be the case?
I strongly disagree with this idea that we would never have evolved past some simple tribal life in the equatorial area's. There are many reasons beyond seasonal/ice-age/etc to travel around - and the temperate areas would still need fire tech. give it a long enough timeframe (hundreds of thousands of years) and I think we are more than that assumption, but how much more per unit of time? Who can ever say.
I know what you mean BINARYGOD. The whole idea is stupid to the point of being offensive. Ecological anthropologists should consider that if cold is such a stimulus to civilization then why do the Inuit have such a simple level of culture? Ditto Laplanders. It's still under debate whether the Nordic Vikings were anything more than brutal savages yet advocates of Nordic superiority swear on a Bible that every human advancement came from this one ethnic group. In reality left to their own devices they never developed past that crucial watershed of permanent settlements we call civilization. They were nomadic marauders preying on the permanent settlements of others like the warm weather Latins of the Roman Empire. Native Americans survived ice ages but didn't develop things like the decimal point until settling in middle American jungles and mountain tops. Before I finish there is a RUclips video dealing with this idea that subSaharan Africans never developed the wheel because they are stupid. That cold climate races developed bigger brains to survive the winter. First it turns out sub-Saharan blacks DID develop the wheel. However, it's an idea that never caught on because there was no need for wheels. They did not need to travel much. What little travel was done was by the use of beasts of burden, not wheels.
Hey everybody likes warm weather... But there's nothing stopping ancient Greeks from building their stone houses with a main plaza fireplace which made the stone of the upper family unit floors warm under their toes (sounds heavenly) in cooler climates. I agree with OP- we are explorers at heart and once the brave had traveled north and south, reporting the wealth of resources, people would migrate as they did with a tilted earth. The proof is the Eskimo such as the Inuit. Living in the Arctic Circle continuously. Fire and their basic technology allowed them to hunt whales and craft amazing weapons - why should anything be so different just because "it's cold" towards the poles?
If there were no tilt of the eart on its axis, now exists , the amount of sun light receiving by earth would be the same for the both position so there is no chance becoming more cold of northern and southern part of the earth
Yes, and somewhere in the galaxy, there is a planet whose axis of rotation is perpendicular to the ecliptic. On THAT planet, there is a Vimeo addressing how it would be impossible for complex life to evolve on a planet wit an axial tilt of more than 1 or 2 degrees. I'll bet it's interesting. A few stars away, there is a planet with an axis that points directly at its own sun (like Uranus). On THAT planet there is a TikTok video showing how it would be impossible for complex life to evolve without this special feature.
What would happen to the climate (particularly ice buildup near the poles) if Earth's tilt were more modestly different than the discussion here of zero tilt? Say 15 or 30 degrees? I've long wondered about that...
If , no, When the polar regions begin to accumulate more snow/ice, sea level will drop - as much as 100 to 150 meters, with coastlines retreating from many major population centers. Additionally, the weight of the ice has significant impact on the geology of the covered continents, depressing those areas covered, while tilting the uncovered areas up, possibly further impacting shoreline retreat.
Uncle Arwin, thank you very much for a wonderful episode, as always! I would really like an episode about the history of the Nobel Prizes in quantum mechanics with a brief description of each! And about the future of the Earth under the influence of the sun in 50 thousand years, 500 thousand years, 50 million years, 500 million years and until absorption by a red giant too 😊
Earth Orbit is dependent on it's Surface 9.8 Energy Conservation System Activity's, Concerving Sunlight Photons Energy's at Quantum level's in real time, to obtain, and maintain a weightless freedom of Orbital MOTION that instantly takes on stream lined up grades for Velocity, Spacing, Rotation, and Tilt, last but not least. Tilt is always in aggressive mode monitoring the Land Scape to open the widest possible areas for incoming Sunlight Photons Energy's Conservation, it's life line to stay in a weightless Orbit. Weightless Space Object's are easily powered by Photon Energy's. 😮 Photons Raining down to Earth creates a Surface SENSATION causing it's weightlessness to easily respond in a Tilt fashion.
@drkdrk7 Understood ! U're one of eight billion who believes in the Mythical Gravity MOTION, even when your very internal, and external Body MOTION are Energy driven, including Earth Surface 9.8 Energy Conservation System Activity's, such as Hurricanes, Tornadoes, Dirt Devils, Earth Quakes, Volcanoes, Atmospheric Wind, Satellite, Plains, Birds, Tectonic Plates, Earth Core, Lightening, Ocean Waves, Wild Life, Rising Gase's, Earth Magnetic Field, Aurora Burialis, Bullets, Cars, Clouds, Rocket Lift-off, Web Telescope, Marine Lives, Photons Energy Raining downward to Earth Surface, these are all Science FACTS of Energy's in MOTION. Warning: The Air U breathe Debunks Gravity in multiple ways, it keeps your Body in MOTION, It enables Ocean Waves, and Tree Leaves into MOTION. No one has to believe anything.
Yes, no tilt would have impact to evolutionary lines, yet evolutionary lines also rely not just on fittest, but also on luck, those lucky early propagate more with quantity being its own kind of fitness. Series of normal distributions yield Pareto distribution. Hence, even keeping the tilt, were you to simply rewind the clock and run again, you’d get a different earth in terms of flora and fauna.
Bill Gates wanna experiment with covering the sunlight and blow nukes on the Moon! When you read about his ideas and think about the influence he has with his money its scary? What if Bill Gates push away the Moon and block the sunlight and stop Earths tilt for fun? Gates have the money to travel and love on Mars and have a laugh terraform Mars and zip a drink meanwhile chaos and extinction follows on Earth!
@0:45 what's that? the tilt is responsible for our climate and seasons? Well maybe that is what is driving this "climate change" crap. It's also interesting to note that in the 1980's when the climate was actually hotter, the tilt was only 23 degrees, so half a degree change in the tilt can make quite a difference, it would seem.
I totally agree. Homo sapiens could not have arisen on a planet without an axis tilt. But not only because of the absence of periodic winter, but also because of the general stability of the climate. After all, our large brain developed precisely because of the need to adapt to major climate changes, which lasted not months or millions of years, but hundreds of years, when centuries of rains were replaced by centuries of drought, forests grew in the place of steppes, etc.
I wanted to add several points. Firstly, let's imagine that the Earth's axial tilt was not 23 degrees, but 90 degrees, similar to Uranus. In that case, the length of the terrestrial day would not correspond to the period of rotation. You would have a North Pole pointed at a tropical sun for months on end that would burn and sear that part of the Earth with 24 hours of TROPICAL daylight for months. Imagine a relentless demonic eye, burning the world. Meanwhile, the South Pole is plunged into 6 months of darkness. But this darkness would encompass a far greater portion of the globe than it does presently. The possibilities for snow and ice, and sea ice, would therefore seem infinite. The 64,million dollar question would be which side would predominate: the seating eyeball heat storm, or the maelstrom of winter glaciation? Secondly, let's all remember that although the Earth's ractual axial tilt has remained steady through the ages, it can actually wobble a little bit. It varies between 22-24 degrees. Yes, the pole wanders around in a circle, but the actual tilt is still very stable. Now suppose that the North Pole lists just a little, and we get a tilt of 24 degrees. Surprisingly, we get big effects. The African monsoon becomes a big factor in the Earth's climate. Suddenly, we get a greening of the Sahara. Water falls on the bare sand. Plants spring up. Game animals move north. Giant lakes appear, and once lost, mighty rivers start their flow. The result: a Sahara savanna, full of animals for men to hunt. It is no surprise that when different hominids left Africa, they did so when the Earth's axial tilt was 24 degrees, and the Sahara was a savanna. I am trying to imagine what those huge ancient rivers and lakes must have looked like. Certainly, the River Nile must have been very different. In a wet climate, it becomes a huge, long marsh. The ancestors of the Ancient Egyptians did not live there then. They might just go there to hunt, until that primeval river dried out a bit.
It seems that this ‘wobble’ or tilt of earth could allow many reflection of the suns direct rays from building up (in a fixed centre axis rotation) too
Arvin, you left out the wobble of the earth that causes the seasons to change over the "Great Year", and the fact that tectonic plate movement and vulcanism would continue. Also without the changing weather patterns and wind shift, it might not deposit much snow at the poles. One thing is sure though, it would certainly be different than it is now. A rally interesting subject to cover would be the shifting of the actual poles by 10 or 20 degrees!
The shifting of the poles by “10 or 20 degrees” is referring to the magnetic poles, not the geographic poles. Magnetic poles wander around, and occasionally flip North for South, the geographic poles are quite stable. There is a “precession of the equinoxes” which is the roughly 26,000 year cycle of the movement of Earth’s axis of rotation to move with respect to inertial space, similar to how a spinning top will have its axis of rotation precess in a circle.
@@jpe1 Yeah, I know all that, but I'm talking about the geographic poles, which are moving and have shifted a lot before. I know you think that the geographic poles are stable, but they are not. They are much more stable than the magnetic poles, but they do change and it would cause massive disasters if it happens again!
What would happen if the tilt was opposite? If the summer and winter seasons were flipflopped. The elliptical orbit would be opposite hemisphere in winter. More ocean water is in the southern hemisphere. It would have more effect on weather than no tilt.
That actually happens on a very long time scale. It's one of the factors of the Milankovitch cycles. Meaning eventually Earth's Northern hemisphere will be closer to the sun in summer and farther away in winter (the opposite of what it is now). Making the Northern hemisphere seasons more extreme (hotter summers, colder winters).
it mean winter is longer in north and summer shorter in north too because earth move faster in january around the sun, because we are closer from the sun and slower in july, because we are farther from the sun i read the difference is 2weeks
Earth is not habital in the long run? Its to unstable to sustain a culture who made advances like we done? Solar flares Tsunamis, Volacano eruptions and magnetic disturbances and we have to start over again? Its not Impossible that there could have been advance civilisations on Earth before?
Earth axis has a rotation as well as the earth rotating upon said axis. The axial rotation of earth takes 25,920 years, also known as the procession of the equinoxes. This information is not new! It was written down thousands of years ago in ancient Sanskrit literarure that came from India
That nifty tilt comes in handy to stimulate math. It's nice to know how many days till the beginning of planting, and the near last day to sow. And just how long is this lower light levels of winter going to last. But even if the Earth didn't have such a "drastic" tilt the stars at night could be used as some sort of counting mechanism. The sun rises on the same spot on the horizon and sets on the same opposite spot on the horizon. So there would very little help there for math skills. But at night, the stars move and change positions from day to day, to weeks, and so on as the Earth revolves around the sun. Always changing positions in a rhythmic way. That may just be what a new developing brain can use as to explore the why the sky changes at night. And that in turn could bring about a super intelligence just like Man.
Surprisingly this does not appear to be the case. On Jan 2, Earth was as close to the sun as it will get in its elliptical orbit yet we have the coolest weather of the year around this time in the Northern Hemisphere. In July, when Earth is farthest from the sun due to its elliptical orbit, we have the hottest weather in the Northern Hemisphere. What little effect the elliptical orbit has on seasons appears to be overwhelmed by the effect of the axial tilt.
Earth would be a permanently frozen snowball without the tilt. Do the ice caps melt on March 21, (or April 15 to account for the lag effects). NO. The glaciers would get bigger and bigger and reflect more sunlight and even the tropics would eventually freeze over. The oceans would be considerably smaller and perhaps 1000 metres less deep as so much would be locked up in the glaciers. I built an albedo model and it would take very little change in the solar insolation hitting the poles before this would happen. Maybe even just 3 degrees less tilt would result in the same snowball earth.
At 1:31 he describes the planet Theia's collision with earth as a factual, historical incident only to 'stress' at the end of the story that it is just an hypothesis.
It's the best theory we have. Modeling shows we end up with the earth/moon system we have now. Analysis of materials from earth & the moon are consistent with this explanation. So it's not just a random hypothesis. There are probably minor details to be tweaked, like with the big bang as well.
This might explain the lack of detectable alien techno signatures in our part of the universe. the Theia fluke impact plus the combination of other flukes like the creation of the moon in that impact and the dinosaur wiping asteroid and so on. All of these rare events gave earth the "winning ticket" for a civilization to thrive.
In reality, humans need pretty specific conditions to live. Many organisms like bacteria can survive extreme temperatures. We need temperatures with a very small variance to survive. Cold temperatures especially are deadly without shelter. In extreme heat like 120F, you can do things to survive. Find shade, conserve energy, stay hydrated if you can. Stranded at -20F with no shelter and with a few hours you’re about to freeze to death. That’s a pretty small range for life to exist. Any slight change to earths orbit or tilt and we’d either be too hot or too cold.
*"what if it was 35 degrees"* Some things that would happen: Seasons become harsher, due to longer days and sun reaching higher angles in the sky in summer and the opposite in winter. Polar areas become a little less cold due to higher sun angles in summer Equatorial areas become a little less warm due to lower sun angle at the solstices
@@boulderbash19700209 yes. But in high latitude areas there is close to ZERO sunlight in winter, so increasing tilt barely changes sunlight in winter, but drastically increases sunlight in summer making the place overall warmer.
@@boulderbash19700209 it also mean summer and winter going to harsher, because more spot will be longer time in 24 h day and 24 h night, so it will have more time to be hotter and cooler it may mean new york may see at least 24 hours of full day and full night once by year while solstice
Losing seasons would be a problem, but the change would be gradual. We would have lots of time to adapt, and save the species we like most. If it happens quickly it would be due to a collision with a large asteroid. In that case, a change in the tilt would be the least of our problems.
No axial tilt since the earth cooled down after formation and perhaps Thea would have cinched the frozen earth described herein. That’s way, way earlier than life even became established. Everything would be vastly different, beyond conjecture.
The greatest paradox seems to be that, in spite of the monumental odds against our existence and the fact that we are here at all, we seem so intent on sterilising this planet. The jury is still out on whether there is really intelligent life on earth.
Many highly sophisticated societies developed ib the tropics. The human species evolved in the tropics. Fire was first used in Africa. Tropical Africa developed iron-working indepedently...I could go on...Also bio-diversity ishighest in the tropcs.I could go on..
I have forgotten the author of the following quote but he stated about the moon, "It is far easier to explain why the moon doesn't exist than to explain that it does". That's how weird our moon is.
While I can believe that a zero-degree tilt might accumulate ice at the poles, I do disagree about animals and plants. A stable climate without seasons only means that the weather stays the same at the same latitude. (Except for things like the Gulf Stream keeping Northern Europe warmer than, say, Siberia on the same latitude, just like it does today.) Animals and plants are dependent on seasons just like they are dependent on night and day. 𝙏𝙝𝙞𝙨 𝙞𝙨 𝙧𝙚𝙥𝙧𝙚𝙨𝙚𝙣𝙩𝙚𝙙 𝙖𝙨 "𝙬𝙞𝙩𝙝𝙤𝙪𝙩 𝙨𝙚𝙖𝙨𝙤𝙣𝙨 𝙩𝙝𝙚𝙮 𝙘𝙤𝙪𝙡𝙙𝙣'𝙩 𝙚𝙭𝙞𝙨𝙩", 𝙬𝙝𝙞𝙘𝙝 𝙞𝙨 𝙩𝙤𝙩𝙖𝙡𝙡𝙮 𝙬𝙧𝙤𝙣𝙜. Let me explain: Whatever the environment, nature learns to cope with it. After coping, nature finds a way to actually gain from it, whatever properties it does have. If you understand this, then it becomes trivial to see that if we had no seasons, nature would thrive just as well, but birds wouldn't migrate, and they could lay eggs any time, knowing that there's just as much food around. Farmers would get several crops every year everywhere (except on the ice caps, etc.). -- As an example: what if we didn't have night and day (yes, impossible, but humor me, please)? Then animals wouldn't need to sleep at all! Sleep exists because it is dark in the night. Since you can't see and do anything, the bodies of animals use that time for recharging. But with no nights, species would do the recharging on the fly, just like those sea birds that never land. They can't sleep either, or they become shark food. Sharks need to swim 24/7 because they have no air bladder. On a zero-tilt planet the species of plants and animals would be more stratified along latitudes than on the Earth. But just as abundant.
I highly agree that the earth gained a lot from the tilt and seasons. But, if it were to be influenced and started a path to no tilt, I'm not convinced that it wouldn't all work itself out on the big scale at any time of Homo Sapiens existing. We might loose some species, but there would still be a lot of variables and everything else would adapt. One item not mentioned - if the influence that caused the tilt to vanish didn't jack with the moon, then the tidal bulge would play differently, reshaping some of the land, right?
I have often wondered how the Earth would be without a tilt but didn't get many answers here, more 'this wouldn't happen, that wouldn't happen.' Bird and animal migration would be completely different. Trees wouldn't have annual rings as there would be no seasons.. Would the oceanic currents change and would that change the weather more? The video was interesting but unsatisfying.
The tilt of the earth causes four season. This four season causes hot and cold pressure. The cold wind will flow to hot aera. This will bring rain and also ocean current flow. If you want to know a planet have water or not, the chances it will have water when it tilt at certain degree.
The 360 degree ball stays upright wherever it is placed and has no chance of tilting. If the earth is 360 degrees round like this ball, then how come the earth only rotates at 23 degrees tilt? This means that the earth is not spherical in shape. Can scientists explain these doubts?
I don't think Dr. Attwood would be correct here. Generalizing technology as a way to keep warm is just false. Humans still would likely have invented the plow and learned to farm. The plow is regarded as the beginning of industrialization, not fire.
suppose 0°_tilt, both poles have ice caps permanently growing and growing! over time, at one point (= epoch in time; not point in geometry) the Northern ice cap would sit on the ocean floor and continue growing further in height. Would it grow so high, that the Earth's inertial mayor axis, and therefore the rotation axis flips 90° (even if the moon's gravity and the equatorial-rim try to stabilize Earth's Equatorial rotation)? Or Earth's stable rotation, would alter into a flip-flop rotation, on the other 2nd-axis?
So, what does axial tilt indicates? If all planets have one? Was the early solar system more packed and a free for all, those that remained are the ones that cleared and stabilized their orbit? Not just planets but protoplanets too.This is consistent with computer simulation and the formation of the Moon. Maybe throw in there Jupiter and Mercury small tilt base on mass, the inertia of Jupiter and the Sun defending Mercury.
The Eskimos, or Inuit, live in the acrtic, but didn't develop into an intelligent species while living there. They migrated to the arctic from the warmer climates in Africa and Asia. I doubt that an intelligent, tool making, humanoid culture could develop in a climate of permanent subzero temperatures.
It may have been pertinent to point out that the Axial Tilt varies between 22.1 degrees and 24.5 degrees, the cycle is around 40,000 years, and that our seasons are drastically affected over time by the change. This change in tilt play a role in Milankovitch Cycles and, so it is theorized, the ebb and flow of ice ages. We are in an inter glacial period now.
and right now we are closest to the sun during S Hemisphere Summers and futher away during their winters. You would expect s hemishere would have more extreme seasons but they don't because there is much more water and less land than N Hem which heats and cools slower. But all those orbital factors change over time and of couse there is continental drift. A lot of stuff going.
That’s what I’m talking about. That’s what I was saying earlier. You hit it on the news but much better than I did.😅❤🎉🥇🥵🔥😎👍💯👁️👁️
Yes, great point. The Milankovitch cycles include the elliptical orbital cycle of about 100,000 years, and also recession of the earths axis (tilt) so in 13,000 years summer in N hemisphere will occur in January (26,000 year cycle). So what will be the outcome of summer in NH coinciding with being closest point in orbit to the sun? I assume we’ll be deep in an Ice age for the reasons you mention (waters specific heat capacity), but unfortunately I won’t be around to find out.
I think it’s also pertinent to point out that the moon stabilizes our axial tilt.
@@jefferytokarsky1930 I think so too
"Ironically we are currently closer to the sun during winter."
The southern hemisphere enters the chat...
This summer is murderously hot 🥵
Yes, a bit of hemispherical chauvinism on display there!
@@mjmulenga3 Yeah I am pretty sure the sun is going through the most active phase of it's 11 year cycle. Lots of solar flares and such.
@@thejuanderful I read somewhere that this is the hottest year in recent memory in this corner of Africa. Feels like it.
Ah...the lands in proximity to the North Pole. That got labeled mistakenly the South Pole.
There are so many random factors that allowed life on Earth (e.g., magnetosphere, big satellite moon, Goldilocks Zone) that it comes as no surprise how rare life is in our galaxy.
How on Earth do you know how rare life is or isn't in our galaxy?
We haven't seen any yet. @@manshonyagger
@@drbuckley1 There could be millions of civilizations - even broadcasting ones - in our galaxy, and we might not know a thing about it.
You could be right, Anything is possible. Given the vastness of not only space but also time, it would be a remarkable coincidence to detect a signal in the short time that humans have been listening.@@Abmotsad
@@manshonyagger Because life has never and will never come from non-life. Yeah....we have a Creator called God.
Interesting video, as always Alvin, but with many speculations. We used to say too that we, humans, exist thanks to the meteor that kill the dinosaurs. What grows in winter could grow in the regions that will have cold weather. There are solutions to the "new" problems you presented. Anyway, you always present a case that make us think as scientist, and this is what I like the most! Thank you so much for that!!!
I'm not going be a backseat driver. Thank you for the video, it was thought provoking. I especially like how you present the material, its easy to understand and digest. Keep up the good work.
Your part concerning snowball earth - would the effect not depend upon how much free water was available to create snow/ice? And consider that evaporating the oceans to a major extent would lead to a very salty - and thus possibly unfreezable - liquid.
When salty ocean water evaporates, it leaves behind the salt and absorbs the water molecules which would be freshwater😊
long time , no see Mr Ash. Good to have you back, Merry Christmas -:)
thank you. Merry Christmas to you as well.
Was about to ask a stupid question....glad i waited to see the end.
Small issue: The implication that without the Moon we wouldnt have a tilt. The opposite could be true, that without the Moon stabilising the Earths axial tilt, the tilt would swing wildly around (Well, wildly on geological time scales.) This would also produce a whole host of problems not only making life different, but much more difficult.
Im not sure how well proven the stabilising influence is, but assuming it is the case to produce the effects in the video youd somehow need to capture a big moon or otherwise stabilise the Earth without our being knocked over at all in the process.
Yes the moon does stabilize Earths tilt. But without the event that created the moon, how would the tilt have formed in the first place?
@@ArvinAsh I wouldnt have thought the nature of planet formation as we understand it would be inclined to produce a perfectly vertical align planet that can remain stable by chance. This seems to be born out by the other planets with their wildly differing tilts and Mars which has been investigated in great detail and is understood to have swung by 10 degrees in just the last million years. Though I dont know all the mechanics involved.
@jk0621 Yes, it does. It is quite possible that Mars too was similarly hit with a large celestial body but ended up absorbing it over time, such that it did not form a large satellite.
I have think the gyroscope functions in no gravity situations so the earth would be the same in space. It's just a big gyroscope.
According to recent estimates, axial tilts do not vary as much without a moon as previously thought. Originally, it was thought to be 20+ degrees, now its thought to be 5-10 degrees at most for a planet as large as earth, coupled with the fact there is a large gas giant only 4 AU more distant from the sun that banks on the eqrth (Jupiter is thought to be the main cause of the milankovitch cycles, with Venus being less so).
Growing up in Canada where we have long nights in the winter and long days in the summer, it was not a difficult concept to understand since we experience it directly. Explaining this to my friends who move here from tropical countries takes some effort. I have been to the far north when the sun was high in the sky at 2 AM. Really messed with my sleep.
I always tilt towards Arvin's videos! 🎉😊
Coal was mined and used to a small extent during Roman times and possibly before that, what happened in the 18th and 19th centauries was it was mined in ever greater quantities probably due to wood becoming scarcer in places like England due to increased ship and house building so less for fuel.
Great video Arvin!
Hi Arvin, for a spherical earth when we say that it is tilted, what does it specifically mean
A. Is the actual "North Pole" or northern most point on earth not at top of the sphere but shifted out 23 degrees
B. Axis along which spin takes place is tilted but "North pole" is still at top of sphere
C. Both North Pole and magnetic North Pole coincide with axis and are not at top of sphere
Your insight will really put things in perspective for me. Thanks
The axis of rotation of the earth is tilted relative to the plane of earths orbit around the sun.
With no tilt I would have to believe that the weather extremes would be much greater as both heat and cold areas would be more concentrated creating much stronger mixing layers.
I've always wondered if a locked planet, eg Mercury, with a super hot face and freezing cold rear face, has a goldilocks zone at the interface, and how thick that zone would be.
With no Moon to stabilize it's tilt, Earth's rotation would become unstable, wobbly, and prevent any consistent weather pattern over a long enough time to permit the evolution of life.
@@martinsmith60491 inch maximum. Enjoy the view.😅
Without axis lilt there would be only one spring season..after third world war..i.e, after dropping nukes at North pole and South pole earth axis would be zero degree lilt. This will happen in 2036.
Then after 2500 years due to natural calamities the earth axis tilts by 23.5degrees.
This world drama cycle repeats every 5000 years identically second by second. What ever is happening has happened a cycle ago.
I think a locked planet such as Mercury would need some type of atmosphere in order for a temperate zone to exist.
Besides haveing a 23.5 degree tilt, Earth's axis also wobbles like a top. Wobbles anywhere from 22.5 to 24.5 degrees. More upright the axis, ice age, more tilted, global warming.
Thank you for developing this topic. I thought that the lack of axial tilt would lead to constantly raging strong storms due to the difference between equatorial and polar temperatures. Was I wrong about this? :)
Pretty sure the lack of tilt would lead to stratification, & thus the atmosphere would be relatively calm, with no "trade winds" or ocean conveyor belt cycles. So there would be less opportunity for storms. The seasons cause the atmosphere to mix & move around (trade winids, oceanic conveyor belts), generating storms.
@@sideshowbob But wouldn't the huge temperature difference between the equatorial and polar regions just result strong winds?
@@merion297 You need something to mix the areas together, such as axial tilt does. Picture a blender in which the ingredients for a Margarita have been dumped into, but the blender isn't plugged in. Very little mixing will occur.
Sure, the elliptical orbit of the Earth, various tectonic forces, & the gravitational tug of the moon might provide some energy, but possibly not enough to overcome atmospheric "drag".
This would be an interesting scenario to model, such as they are doing to forecast the effects of climate change, but the computing power to do so is beyond the reach of armchair speculators such as us.
Just basic logic but it would far more likely that things would move in a different pattern than come to a standstill. The 'blender' (the sun) is always plugged in. Even if always the highest over the equator the difference in more water being evaporated here would surely lead to movement around the earth. @@sideshowbob
@@barleyeducated8714 Well it's like predicting the results of human induced climate change. The Earth's climate is such a complicated system, with so many variables, even our best computer modeling attempts are still primitive & not definitive. This would be the same. More fun for us to randomly speculate lol.
I like how people talk about events from billions of years ago like they were there.
I don't agree. That's a pretty tough "what if..." to figure out. There are no seasons within a few degrees of the equator and that's probably where humans started out. It's hard to judge what edible plants would be around because the plants we have now evolved with the seasons. Half the plants on earth now evolved in the equatorial zones with no seasons, (... life finds a way"). It doesn't take much science or imagination to see plants evolving in the cooler regions. Humans would settle in the comfortable regions. As far as innovation, we can only guess. People living in that world would think living someplace where the temperature swings by a 100° would be hellish.
I think living in a world where you could migrate to your comfort zone and not have seasonal changes would be very peaceful.
Life is a mathematical impossibility unless someone created it in a perfectly designed setting. More than 2,000 variables have to line up just for life to be possible on a planet. Life would also be impossible were it not for our perfectly placed moon causing tides.
*life as we know it.
Big distinction.
Variation in the tilt probably causes ice ages but albedo is not the only possible positive feedback. An asymmetric buildup of ice would shift the moment of inertia not to mention groundwater distribution. So cause and effect is not so straight forward. A simplistic correlation of tilt with ice ages has its problems. Not to mention variations in sun luminosity.
Love it, hooray Arvin!
What if the axial tilt was much greater, like 50 degrees?
Go spend a few Uranus years on Uranus and let us know :)
Our seasons would be much longer and hotter/colder. An example of this is the planet Uranus which is orbiting the Sun tilted at 82.23º, as if it was rolling. Winter at the poles last 42 years each during its 84 year orbit around the Sun. (Its poles receive more energy when they face the Sun but for unknown reasons the equator remains warmer.)
@@JohnnyAngel8 Makes sense. I guess Spring and Autumn would be shorter then, right?
@@JohnnyAngel8 Maybe because its equator still receives sun light the entire year while each of the poles have chance to shed its heat for half year at a time.
more intense season, tropical temperature at summer in pole area
and it going to snow in tropical area at sea level, even equator may see snow at sea level at summer and winter solstice
the bottom line is that EVERY object in the universe is MOVING and SPINNING. the amounts of both can vary widely, and they do
very clear explanation like a mass telecommunications expert.
How do we know Earth wasn’t tilted before Theia?
We don't. But even if it was, the collision still would have had a dramatic effect. Probably incurring the current tilt.
I get the feeling (just a quick thought), that not having an axial tilt would be conductive to aquatic lifeforms to develop more efficiently than terrestrial ones, since water acts as a safer, denser medium than air and it also offers some padding and intermixing of temperatures between latitudes due to currents maybe?
Considering winter to start on the solstice is plain crazy. 😂
That's why we have astronomical and meteorological winters. The first is in reference to astronomical points in the Solar System; the second is in reference to the three coldest months of the year. Our calendars only list the astronomical moments.
I do think that calendars should show "solstice" and "equinox" rather than "winter begins" and "autumn begins". Maybe some do but I haven't seen any.
As the Earth's temperature changes lag behind changes in the amount of sunlight received, it makes some sense to start seasons with the solstice or equinox. When I moved from the US to Australia 30+ years ago I found it strange to arbitrarily tag seasons by the calendar - first day of Summer is Dec. 1st, first day of Autumn is Mar. 1st, etc. In reality "seasons" are just convenient divisions around the solstice and equinox, and we can tag them however is convenient. Why not eight? Or two? Many tropical areas have a hot, a wet, and a dry season. That works for them.
Thanks!
Please also cover the oscillation of the axis and results thereof.
Our solar system is a true work of art. The relationship between the sun, moon and earth is so amazing. It's almost like a matter of sheer coincidence, especially when it comes to the seasons and the lunar eclipse. The coincidence behind the distances between the sun, moon and earth is mind blowing. As I say, a true work of art. As if it were designed to be that way. Good thing too. Just look at our existence, and how animals and other forms of life thrive in their natural state.
I have a strong feeling / impression that days (24 hours) have been passing faster than they did a few years back. I solicit your valued opinions
The giant Japan quake a decade ago may have altered our tilt.
There are many who say the same! I feel it as well! In 2012 the transformation started and it ends in 2030. Hence the Orwellian UN Agenda 21/30, World Economic Forum "Own Nothing and Be Happy!" by 2030.
4:11 why you don't specify that you're talking about the Northern Hemisphere. Since it's the opposite season in the Southern Hemisphere. So it's not ironic that Northern Hemisphere Winter is when we are closest to the Sun, since it is also the Southern Hemisphere Summer.
Just like he said, because the main contributor to seasonal temperature variation is earths tilt and not it’s distance from the sun. Saying that it’s summer in the southern hemisphere when the earth is closer to the sun confuses that point.
In 1437 grandson of Timur the Great Ulugbeg measured Earth axial tilt as 23.5047 or 23 degrees 30 minutes and 17 seconds by his quadrant in Samarkand observatory. In 2022 Earth tilt was about 23.4365 degrees. Difference in 585 years was about .0682 degrees, it makes 0.1166 degrees of changing of tilt for millennium. Tilt of Earth currently s being reduced until reaching a minimum value of 22.1 Degrees. Maximum axial tilt of Earth in 24.5 degrees was in 7068 BC in the last cycle.
My dad always said the Earth's axis is tilted because there are more horses asses than horses.
Your dad is not wrong...in the metaphorical sense. lol.
@@ArvinAsh It's always lived rent free in my brain.
I truly believe that your dad is correct.
With the ice caps building in depth the ocean levels would fall revealing more and more land surface. As temperatures fell hot arid regions would become livable and able to sustain crops. So maybe it would not become a 'problem' for tens of thousands of years if at all.
Question re the shortest day: the day with the earliest sunset is December 7. After that, the afternoons get a bit brighter later. The day with the latest sunrise is January 7; after that, the mornings get brighter earlier. What causes this? The 'shortest day' is actually the day midway between these two dates.
I've thought about this myself, but have never read anywhere as to why this is. So, I tried to come up with an explanation on my own. I suspect it may be due to the affects of the sidereal day. This is where the earth actually has to rotate 366.25 times a year in order to produce 365.25 days. It therefore also needs to rotate relative to a fixed point in space about four minutes faster than the 24hrs/rotation we experience in terms of day/night. If you could imagine for a moment a situation where the earth was "frozen in place" rotation-wise (meaning it didn't rotate at all), but still revolved around the sun normally, you would come to see that for each year, you would in fact have one full day - albeit a day that would take a full year, not 24 hours. With this day though, the sun would slowly rise in the WEST, and eventually set in the EAST about six months later. It would be a sort of long "backwards" day. In order to overcome it, and produce the 365.25 days we experience, you need the 366.25 rotations, which requires a touch more speed. As to what this has to do with the earliest and latest sunrises and sunsets being offset from their respective solstices, is that the reverse effects of the sidereal day is overcoming the very slow changes in sunrise and sunset that occur just before and soon after the solstice. If you consider this like a bell curve where the change in the length of the day approaches zero and then begins to reverse at the crest and trough of the curve, at those points the effect of the sidereal day is able to overtake the regular effects of the changing length of day since it is either approaching or slowly moving away from zero. It's sort of like in December the sun is setting earlier and earlier, but it is doing this ever more slowly, because things are soon about to reverse. The sun would keep setting earlier until the solstice in the second and third week of December, but the earth revolving around the sun is now having a greater effect on the day. The sidereal "backwards day" whose small effect is now relatively stronger, is able to kick it in the other direction a couple of weeks before you would normally expect the reversal. The sunrise meanwhile is occurring later at a greater rate than the sunset is happening later, but this changes at the solstice where the later sunset overtakes the later sunrise, which itself will not reverse for another couple of weeks - about the beginning of the second week in January. The two reversals are about a month apart, and again I think the effects of the sidereal day account for all this. Does any of this make sense? I perhaps haven't explained my suspicions effectively, or I'm simply incorrect. I sit around and sometimes speculate about things I've noticed but have been unable to really look up. The sidereal day thing I was able to look up a while back, after it struck me that you needed 366.25 rotations because of this "backwards day" that's created by going around the sun. I suppose that I could try typing in "solstice sunset/sunrise offset" or something like that to figure this out, but I have frankly begun hitting the Heineken's a bit early today and I barely was able to write out this mishmash. Anyway, cheers!
I've also read that less tilt = colder poles and warmer tropics. More tilt, inverse is true.
In general, yes that would be the case.
The minute I saw the title, I was reminded of Immanuel Velikovsky’s ‘Worlds In Collision,’ where he imaginatively describes where the North Pole was depicted as being cantered on the Boothia Peninsula, where the earth’s tilt was changed from where it was then, to where it is now, changing the temperature of areas in Siberia so much, that animals literally froze. All kinds of ice age species have been discovered in Siberia tens of thousands of years old almost perfectly preserved, while on the other side of the earth, whole areas of the northern part of the North American continent were suddenly made liveable.
Cool dude , there has to be a reason how a wooly mammoth freezes with undigested food in its stomach huh ? No one even contemplates this dynamic but you do 😊
@@rogerwolfe1888 Yes, I was quite fascinated with the explanation, though the probable causes of drastic climactic changes are perhaps due to much less dramatic swings than the earth shifting on its axis to that extent. A dramatic climate change occurred in 536 AD, due to a volcanic eruption which had been recorded in tree rings and ice cores, so if there were a volcanic eruption in the era of 40,000 years ago, this could be the cause. If there were a shift recorded in recent geologic timescale, there would be some evidence in the cores of drill samples in the oldest glaciers. Velikovsky’s imaginary prognostications set out from times without a real geological scale of events.
The curious outcome of catastrophism would be that the ‘end of the world’ has already occurred.
@@effingsix3825 Do you have any thoughts on crustal displacement theory ? It is hard to prove but Einstein was very curious on the subject and we know the continents have gradually shifted over great periods of time but dramatic shifts of the earth crust is not usually accepted ! However some geological research does show that not all uplifts and geomorphology are slow but could be dynamic movements ! Any way I’m just an amateur who likes to think about such matters ! Have a nice day
@@rogerwolfe1888 I suppose that the earth’s mantle is a matter for geologists(good article in Wikipedia), though I really like the idea that the earth was once much smaller in size and literally grew, which separated the continents. There’s no evidence this is correct, except that the continents fit together quite curiously should the earth have been smaller at one time.
I like the Electric Universe’s theory that earth was once a satellite of Saturn, which was at one time a brown or red dwarf that was captured by the Sun. This explains why the earth’s tilt is the same as other planets, which were once satellites to Saturn before capture. Other planets don’t have the same tilt. The solar system is quite unique in that it has smaller planets in the inner orbits, while gas giants such as Saturn, Jupiter, Neptune and Uranus are at the outer part of the system, quite the reverse wha5 is found in astronomy.
@@effingsix3825 that is fascinating and even in some ancient mythology Saturn plays a dominant role in how they view their creation ! Your probably very close to the truth because the migration of continents from Pangea makes more sense when you expand , it seems more natural and I’ve always wondered how the continents could migrate ? Thanks
Earth , Mars and Saturn all have about the same tilt. Doesn't the theory of how earth got it's tilt from a planetary collision then mean that these other planets also had the same type of collision, and isn't that just bit too unlikely to be the case?
Northern-centric view indeed.
Thanks, Arvin. I really enjoy your videos and your delivery style. Been following you the past three years or so.
I strongly disagree with this idea that we would never have evolved past some simple tribal life in the equatorial area's. There are many reasons beyond seasonal/ice-age/etc to travel around - and the temperate areas would still need fire tech. give it a long enough timeframe (hundreds of thousands of years) and I think we are more than that assumption, but how much more per unit of time? Who can ever say.
I know what you mean BINARYGOD. The whole idea is stupid to the point of being offensive. Ecological anthropologists should consider that if cold is such a stimulus to civilization then why do the Inuit have such a simple level of culture? Ditto Laplanders. It's still under debate whether the Nordic Vikings were anything more than brutal savages yet advocates of Nordic superiority swear on a Bible that every human advancement came from this one ethnic group. In reality left to their own devices they never developed past that crucial watershed of permanent settlements we call civilization. They were nomadic marauders preying on the permanent settlements of others like the warm weather Latins of the Roman Empire. Native Americans survived ice ages but didn't develop things like the decimal point until settling in middle American jungles and mountain tops. Before I finish there is a RUclips video dealing with this idea that subSaharan Africans never developed the wheel because they are stupid. That cold climate races developed bigger brains to survive the winter. First it turns out sub-Saharan blacks DID develop the wheel. However, it's an idea that never caught on because there was no need for wheels. They did not need to travel much. What little travel was done was by the use of beasts of burden, not wheels.
Probably a Type 10 civilization under contract to run universal simulations for that exact scenario could say.
Necessity is the mother of invention.
Most probably it's a very Eurocentric viewpoint.
Even though Europe claims its science to be of Greek origin which is from a warm region.
Hey everybody likes warm weather... But there's nothing stopping ancient Greeks from building their stone houses with a main plaza fireplace which made the stone of the upper family unit floors warm under their toes (sounds heavenly) in cooler climates.
I agree with OP- we are explorers at heart and once the brave had traveled north and south, reporting the wealth of resources, people would migrate as they did with a tilted earth.
The proof is the Eskimo such as the Inuit. Living in the Arctic Circle continuously. Fire and their basic technology allowed them to hunt whales and craft amazing weapons - why should anything be so different just because "it's cold" towards the poles?
If there were no tilt of the eart on its axis, now exists , the amount of sun light receiving by earth would be the same for the both position so there is no chance becoming more cold of northern and southern part of the earth
Great video👍🏽
Yes, and somewhere in the galaxy, there is a planet whose axis of rotation is perpendicular to the ecliptic. On THAT planet, there is a Vimeo addressing how it would be impossible for complex life to evolve on a planet wit an axial tilt of more than 1 or 2 degrees. I'll bet it's interesting.
A few stars away, there is a planet with an axis that points directly at its own sun (like Uranus). On THAT planet there is a TikTok video showing how it would be impossible for complex life to evolve without this special feature.
Is there a RUclips planet? I mean like RUclips runs everything?
😂😂😂
What would happen to the climate (particularly ice buildup near the poles) if Earth's tilt were more modestly different than the discussion here of zero tilt? Say 15 or 30 degrees? I've long wondered about that...
If , no, When the polar regions begin to accumulate more snow/ice, sea level will drop - as much as 100 to 150 meters, with coastlines retreating from many major population centers. Additionally, the weight of the ice has significant impact on the geology of the covered continents, depressing those areas covered, while tilting the uncovered areas up, possibly further impacting shoreline retreat.
Always a good day when AA posts a new episode. That's coming up right now !
this is saying my gurlfriend each time she is about to beat my face
I'm like what are you about to do ?
and she is like that's coming up right now !
I sure agree!
Uncle Arwin, thank you very much for a wonderful episode, as always! I would really like an episode about the history of the Nobel Prizes in quantum mechanics with a brief description of each! And about the future of the Earth under the influence of the sun in 50 thousand years, 500 thousand years, 50 million years, 500 million years and until absorption by a red giant too 😊
Earth Orbit is dependent on it's Surface 9.8 Energy Conservation System Activity's, Concerving Sunlight Photons Energy's at Quantum level's in real time, to obtain, and maintain a weightless freedom of Orbital MOTION that instantly takes on stream lined up grades for Velocity, Spacing, Rotation, and Tilt, last but not least. Tilt is always in aggressive mode monitoring the Land Scape to open the widest possible areas for incoming Sunlight Photons Energy's Conservation, it's life line to stay in a weightless Orbit.
Weightless Space Object's are easily powered by Photon Energy's. 😮
Photons Raining down to Earth creates a Surface SENSATION causing it's weightlessness to easily respond in a Tilt fashion.
@@rayagoldendropofsun397 stop smoking crack dude
@drkdrk7
Understood !
U're one of eight billion who believes in the Mythical Gravity MOTION, even when your very internal, and external Body MOTION are Energy driven, including Earth Surface 9.8 Energy Conservation System Activity's, such as Hurricanes, Tornadoes, Dirt Devils, Earth Quakes, Volcanoes, Atmospheric Wind, Satellite, Plains, Birds, Tectonic Plates, Earth Core, Lightening, Ocean Waves, Wild Life, Rising Gase's, Earth Magnetic Field, Aurora Burialis, Bullets, Cars, Clouds, Rocket Lift-off, Web Telescope, Marine Lives, Photons Energy Raining downward to Earth Surface, these are all Science FACTS of Energy's in MOTION.
Warning: The Air U breathe Debunks Gravity in multiple ways, it keeps your Body in MOTION, It enables Ocean Waves, and Tree Leaves into MOTION.
No one has to believe anything.
Yes, no tilt would have impact to evolutionary lines, yet evolutionary lines also rely not just on fittest, but also on luck, those lucky early propagate more with quantity being its own kind of fitness. Series of normal distributions yield Pareto distribution. Hence, even keeping the tilt, were you to simply rewind the clock and run again, you’d get a different earth in terms of flora and fauna.
I would like to see a discussion of what the Earth would be like if it was MORE tilted; say 30 or 40 degrees.
Bill Gates wanna experiment with covering the sunlight and blow nukes on the Moon! When you read about his ideas and think about the influence he has with his money its scary? What if Bill Gates push away the Moon and block the sunlight and stop Earths tilt for fun? Gates have the money to travel and love on Mars and have a laugh terraform Mars and zip a drink meanwhile chaos and extinction follows on Earth!
@0:45 what's that? the tilt is responsible for our climate and seasons? Well maybe that is what is driving this "climate change" crap. It's also interesting to note that in the 1980's when the climate was actually hotter, the tilt was only 23 degrees, so half a degree change in the tilt can make quite a difference, it would seem.
We have Winter and Summer starting 21 or 22 days before the solstices.
Hello Arvin
I totally agree. Homo sapiens could not have arisen on a planet without an axis tilt.
But not only because of the absence of periodic winter, but also because of the general stability of the climate. After all, our large brain developed precisely because of the need to adapt to major climate changes, which lasted not months or millions of years, but hundreds of years, when centuries of rains were replaced by centuries of drought, forests grew in the place of steppes, etc.
I wanted to add several points. Firstly, let's imagine that the Earth's axial tilt was not 23 degrees, but 90 degrees, similar to Uranus. In that case, the length of the terrestrial day would not correspond to the period of rotation. You would have a North Pole pointed at a tropical sun for months on end that would burn and sear that part of the Earth with 24 hours of TROPICAL daylight for months. Imagine a relentless demonic eye, burning the world. Meanwhile, the South Pole is plunged into 6 months of darkness. But this darkness would encompass a far greater portion of the globe than it does presently. The possibilities for snow and ice, and sea ice, would therefore seem infinite. The 64,million dollar question would be which side would predominate: the seating eyeball heat storm, or the maelstrom of winter glaciation?
Secondly, let's all remember that although the Earth's ractual axial tilt has remained steady through the ages, it can actually wobble a little bit. It varies between 22-24 degrees. Yes, the pole wanders around in a circle, but the actual tilt is still very stable. Now suppose that the North Pole lists just a little, and we get a tilt of 24 degrees. Surprisingly, we get big effects. The African monsoon becomes a big factor in the Earth's climate. Suddenly, we get a greening of the Sahara. Water falls on the bare sand. Plants spring up. Game animals move north. Giant lakes appear, and once lost, mighty rivers start their flow. The result: a Sahara savanna, full of animals for men to hunt. It is no surprise that when different hominids left Africa, they did so when the Earth's axial tilt was 24 degrees, and the Sahara was a savanna. I am trying to imagine what those huge ancient rivers and lakes must have looked like. Certainly, the River Nile must have been very different. In a wet climate, it becomes a huge, long marsh. The ancestors of the Ancient Egyptians did not live there then. They might just go there to hunt, until that primeval river dried out a bit.
I learned so much with this video such as Arvin has hair.
It seems that this ‘wobble’ or tilt of earth could allow many reflection of the suns direct rays from building up (in a fixed centre axis rotation) too
Arvin, you left out the wobble of the earth that causes the seasons to change over the "Great Year", and the fact that tectonic plate movement and vulcanism would continue. Also without the changing weather patterns and wind shift, it might not deposit much snow at the poles. One thing is sure though, it would certainly be different than it is now.
A rally interesting subject to cover would be the shifting of the actual poles by 10 or 20 degrees!
The shifting of the poles by “10 or 20 degrees” is referring to the magnetic poles, not the geographic poles. Magnetic poles wander around, and occasionally flip North for South, the geographic poles are quite stable. There is a “precession of the equinoxes” which is the roughly 26,000 year cycle of the movement of Earth’s axis of rotation to move with respect to inertial space, similar to how a spinning top will have its axis of rotation precess in a circle.
@@jpe1 Yeah, I know all that, but I'm talking about the geographic poles, which are moving and have shifted a lot before. I know you think that the geographic poles are stable, but they are not. They are much more stable than the magnetic poles, but they do change and it would cause massive disasters if it happens again!
Wonderful 👍
Tilt creating seasons and harvests, moon induced tides, strong protective magnetic field - we have all the advantages
Have you reviewed the 3 body problem? Thanks!
What would happen if the tilt was opposite? If the summer and winter seasons were flipflopped. The elliptical orbit would be opposite hemisphere in winter. More ocean water is in the southern hemisphere. It would have more effect on weather than no tilt.
That actually happens on a very long time scale. It's one of the factors of the Milankovitch cycles. Meaning eventually Earth's Northern hemisphere will be closer to the sun in summer and farther away in winter (the opposite of what it is now). Making the Northern hemisphere seasons more extreme (hotter summers, colder winters).
it mean winter is longer in north and summer shorter in north too
because earth move faster in january around the sun, because we are closer from the sun
and slower in july, because we are farther from the sun
i read the difference is 2weeks
I'm never this early .....I guess it already started losing it's tilt
Earth is not habital in the long run? Its to unstable to sustain a culture who made advances like we done? Solar flares Tsunamis, Volacano eruptions and magnetic disturbances and we have to start over again? Its not Impossible that there could have been advance civilisations on Earth before?
Would the masses in the mantle be candidates for leftovers from Thea ?
yes, in fact, I saw a paper about 2 weeks ago where they found evidence that supported your idea.
🙏 Finally I understand it.
Thank you for the content! A little thing to consider - winter does not kill viruses.
Yep. They're digging them up outta the permafrost and toying with them in labs all over this planet.
Earth axis has a rotation as well as the earth rotating upon said axis. The axial rotation of earth takes 25,920 years, also known as the procession of the equinoxes.
This information is not new! It was written down thousands of years ago in ancient Sanskrit literarure that came from India
Bye watching the stars rotate around the earth
I enjoyed your video.
What would a lack of tilt (0 degrees say) have on the formation of the continents, ie: from Pangea to how the continents are shaped now?
Planets knowledge is very different than what we are taught
That nifty tilt comes in handy to stimulate math. It's nice to know how many days till the beginning of planting, and the near last day to sow. And just how long is this lower light levels of winter going to last.
But even if the Earth didn't have such a "drastic" tilt the stars at night could be used as some sort of counting mechanism. The sun rises on the same spot on the horizon and sets on the same opposite spot on the horizon. So there would very little help there for math skills.
But at night, the stars move and change positions from day to day, to weeks, and so on as the Earth revolves around the sun. Always changing positions in a rhythmic way. That may just be what a new developing brain can use as to explore the why the sky changes at night. And that in turn could bring about a super intelligence just like Man.
I also think the elliptic orbits also plays a role in seasons
Surprisingly this does not appear to be the case. On Jan 2, Earth was as close to the sun as it will get in its elliptical orbit yet we have the coolest weather of the year around this time in the Northern Hemisphere. In July, when Earth is farthest from the sun due to its elliptical orbit, we have the hottest weather in the Northern Hemisphere. What little effect the elliptical orbit has on seasons appears to be overwhelmed by the effect of the axial tilt.
Earth would be a permanently frozen snowball without the tilt. Do the ice caps melt on March 21, (or April 15 to account for the lag effects). NO. The glaciers would get bigger and bigger and reflect more sunlight and even the tropics would eventually freeze over. The oceans would be considerably smaller and perhaps 1000 metres less deep as so much would be locked up in the glaciers. I built an albedo model and it would take very little change in the solar insolation hitting the poles before this would happen. Maybe even just 3 degrees less tilt would result in the same snowball earth.
At 1:31 he describes the planet Theia's collision with earth as a factual, historical incident only to 'stress' at the end of the story that it is just an hypothesis.
It's the best theory we have. Modeling shows we end up with the earth/moon system we have now. Analysis of materials from earth & the moon are consistent with this explanation. So it's not just a random hypothesis. There are probably minor details to be tweaked, like with the big bang as well.
Thanks.@@sideshowbob
My question is how would the moons orbit and gravitational effect have upon the tides if the world was perpendicular to its equatorial plane?
This might explain the lack of detectable alien techno signatures in our part of the universe. the Theia fluke impact plus the combination of other flukes like the creation of the moon in that impact and the dinosaur wiping asteroid and so on. All of these rare events gave earth the "winning ticket" for a civilization to thrive.
Anyone else having problems with Arvin’s videos not appearing in their feed?
In reality, humans need pretty specific conditions to live. Many organisms like bacteria can survive extreme temperatures. We need temperatures with a very small variance to survive. Cold temperatures especially are deadly without shelter. In extreme heat like 120F, you can do things to survive. Find shade, conserve energy, stay hydrated if you can. Stranded at -20F with no shelter and with a few hours you’re about to freeze to death. That’s a pretty small range for life to exist. Any slight change to earths orbit or tilt and we’d either be too hot or too cold.
And it's all by chance😅
@ngonihwata2653 Yes, it could've just been chance. A much stronger probability than your book of Iron Age Middle Eastern fables.
Is the tilt of 23.5 degrees ideal for life as we know it, or would a different tilt be beneficial? What if it was 35 degrees?
Uranus has about 90 degree tilt.
*"what if it was 35 degrees"*
Some things that would happen:
Seasons become harsher, due to longer days and sun reaching higher angles in the sky in summer and the opposite in winter.
Polar areas become a little less cold due to higher sun angles in summer
Equatorial areas become a little less warm due to lower sun angle at the solstices
@@HugoFilho. You know that longer day in summer equals to longer night in winter, right? Right?
@@boulderbash19700209 yes.
But in high latitude areas there is close to ZERO sunlight in winter, so increasing tilt barely changes sunlight in winter, but drastically increases sunlight in summer making the place overall warmer.
@@boulderbash19700209 it also mean summer and winter going to harsher, because more spot will be longer time in 24 h day and 24 h night, so it will have more time to be hotter and cooler
it may mean new york may see at least 24 hours of full day and full night once by year while solstice
Losing seasons would be a problem, but the change would be gradual. We would have lots of time to adapt, and save the species we like most. If it happens quickly it would be due to a collision with a large asteroid. In that case, a change in the tilt would be the least of our problems.
what is the least percent of tilt earth could have without turning into snowball?
No axial tilt since the earth cooled down after formation and perhaps Thea would have cinched the frozen earth described herein. That’s way, way earlier than life even became established. Everything would be vastly different, beyond conjecture.
“Cold weather promotes invention.”
Careful…. 😆 This is a dangerous subject!
Indeed.
The greatest paradox seems to be that, in spite of the monumental odds against our existence and the fact that we are here at all, we seem so intent on sterilising this planet. The jury is still out on whether there is really intelligent life on earth.
Many highly sophisticated societies developed ib the tropics. The human species evolved in the tropics. Fire was first used in Africa. Tropical Africa developed iron-working indepedently...I could go on...Also bio-diversity ishighest in the tropcs.I could go on..
I have forgotten the author of the following quote but he stated about the moon, "It is far easier to explain why the moon doesn't exist than to explain that it does". That's how weird our moon is.
While I can believe that a zero-degree tilt might accumulate ice at the poles, I do disagree about animals and plants. A stable climate without seasons only means that the weather stays the same at the same latitude. (Except for things like the Gulf Stream keeping Northern Europe warmer than, say, Siberia on the same latitude, just like it does today.)
Animals and plants are dependent on seasons just like they are dependent on night and day. 𝙏𝙝𝙞𝙨 𝙞𝙨 𝙧𝙚𝙥𝙧𝙚𝙨𝙚𝙣𝙩𝙚𝙙 𝙖𝙨 "𝙬𝙞𝙩𝙝𝙤𝙪𝙩 𝙨𝙚𝙖𝙨𝙤𝙣𝙨 𝙩𝙝𝙚𝙮 𝙘𝙤𝙪𝙡𝙙𝙣'𝙩 𝙚𝙭𝙞𝙨𝙩", 𝙬𝙝𝙞𝙘𝙝 𝙞𝙨 𝙩𝙤𝙩𝙖𝙡𝙡𝙮 𝙬𝙧𝙤𝙣𝙜. Let me explain: Whatever the environment, nature learns to cope with it. After coping, nature finds a way to actually gain from it, whatever properties it does have. If you understand this, then it becomes trivial to see that if we had no seasons, nature would thrive just as well, but birds wouldn't migrate, and they could lay eggs any time, knowing that there's just as much food around.
Farmers would get several crops every year everywhere (except on the ice caps, etc.). -- As an example: what if we didn't have night and day (yes, impossible, but humor me, please)? Then animals wouldn't need to sleep at all!
Sleep exists because it is dark in the night. Since you can't see and do anything, the bodies of animals use that time for recharging. But with no nights, species would do the recharging on the fly, just like those sea birds that never land. They can't sleep either, or they become shark food. Sharks need to swim 24/7 because they have no air bladder.
On a zero-tilt planet the species of plants and animals would be more stratified along latitudes than on the Earth. But just as abundant.
I highly agree that the earth gained a lot from the tilt and seasons. But, if it were to be influenced and started a path to no tilt, I'm not convinced that it wouldn't all work itself out on the big scale at any time of Homo Sapiens existing. We might loose some species, but there would still be a lot of variables and everything else would adapt.
One item not mentioned - if the influence that caused the tilt to vanish didn't jack with the moon, then the tidal bulge would play differently, reshaping some of the land, right?
I have often wondered how the Earth would be without a tilt but didn't get many answers here, more 'this wouldn't happen, that wouldn't happen.' Bird and animal migration would be completely different. Trees wouldn't have annual rings as there would be no seasons.. Would the oceanic currents change and would that change the weather more? The video was interesting but unsatisfying.
The tilt of the earth causes four season. This four season causes hot and cold pressure. The cold wind will flow to hot aera. This will bring rain and also ocean current flow.
If you want to know a planet have water or not, the chances it will have water when it tilt at certain degree.
The 360 degree ball stays upright wherever it is placed and has no chance of tilting. If the earth is 360 degrees round like this ball, then how come the earth only rotates at 23 degrees tilt? This means that the earth is not spherical in shape.
Can scientists explain these doubts?
I prefer my planets shaken, not stirred.
หินเป่า>หินยาน>หิน=ธาตุชนิดหนึ่ง+ สมาธิ +แรงกระตุ้น หรือแรงบันดานใจ=ศรัทธา
I really like your channel, Arvin. Been subscribed for a while now, but you’re a cool chap! We like the subtle contrarianism.
I don't think Dr. Attwood would be correct here. Generalizing technology as a way to keep warm is just false. Humans still would likely have invented the plow and learned to farm. The plow is regarded as the beginning of industrialization, not fire.
suppose 0°_tilt, both poles have ice caps permanently growing and growing! over time, at one point (= epoch in time; not point in geometry) the Northern ice cap would sit on the ocean floor and continue growing further in height. Would it grow so high, that the Earth's inertial mayor axis, and therefore the rotation axis flips 90° (even if the moon's gravity and the equatorial-rim try to stabilize Earth's Equatorial rotation)?
Or Earth's stable rotation, would alter into a flip-flop rotation, on the other 2nd-axis?
So, what does axial tilt indicates? If all planets have one? Was the early solar system more packed and a free for all, those that remained are the ones that cleared and stabilized their orbit? Not just planets but protoplanets too.This is consistent with computer simulation and the formation of the Moon. Maybe throw in there Jupiter and Mercury small tilt base on mass, the inertia of Jupiter and the Sun defending Mercury.
It makes me wonder if the drastic weather change is due to the axis changing . :O)
The Eskimos, or Inuit, live in the acrtic, but didn't develop into an intelligent species while living there. They migrated to the arctic from the warmer climates in Africa and Asia. I doubt that an intelligent, tool making, humanoid culture could develop in a climate of permanent subzero temperatures.