Classroom Aid - Galactic Center
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- Опубликовано: 18 сен 2024
- howfarawayisit....
In this segment of our “How far away is it” video book, we cover the structure of the Milky Way galaxy.
We start with a high-level description of the three main components: the galactic center with its black hole, the galactic disk with its spiral arms, and the galactic halo stretching far out in all directions using the European Space Agency spacecraft Gaia’s findings. We also show how full images of the Milky Way can be created from within the galaxy.
Using the full power of the Hubble, Spitzer, and Chandra space telescopes, we take a deep dive into the center of our galaxy with its central bulge. We detail the evidence for the existence of a supermassive black hole, Sagittarius A*, at the very center of the galaxy’s core. We cover and illustrate the work done by the UCLA Galactic Centre Group in conjunction with the new Keck observatory on top of the Mauna Kea volcano in Hawaii, and the Max Plank Institute for Extraterrestrial Physics in Germany and more recently and the European Southern Observatory with its array of Very Large Telescopes in Chile. This includes a look at how close the star S2 approached Sgr A* and what that black hole might look like. In addition, we cover stellar interferometry with ducks on a pond to see how these measurements were done.
Next, we go a level deeper into the nature of a Black Hole singularity. We cover the Schwarzschild radius, event horizon, accretion disk, gravitational lensing, and gamma-ray jets. We then actually build Sgr A*. In addition to the supermassive black hole, we take a look at a solar mass black hole.
We then cover the structure of the galactic disk including: the bar core, the two 3 Parsec arms, Scutum-Centaurus, Perseus, Sagittarius with its Orion Spur, Norma and the Outer Arm. We review the locations of various celestial objects we’ve seen in previous Milky Way segments, to show how close to us they are. We also cover the disk’s rotation and the Sun’s orbit. We look at our solar system’s Ecliptic Plane with respect to the galactic plane. And we cover the galaxy’s dust clouds and how we see them with radio astronomy. We also cover the galaxy’s rotation curve and its connection with dark matter.
Next, we cover the galactic halo. We start with Shapley’s globular cluster map that first showed that we were not at the center of the galaxy. We cover the size of the halo, the inner and outer halos orbital motion, and the newly discovered galaxy within our galaxy called Gaia-Enceladus. We end with recent discoveries of massive amounts of Hydrogen in the halo and this findings impact on the Dark Matter debate. And we end with a calculation of the entire Milky Way’s mass.
We end our galaxy coverage by illustrating how far one would have to go to take a picture that would include what we see in our illustrations. We conclude the chapter with another look at the distance ladder that took us across the galaxy.
@00:00 Beethoven, Ludwig van: Symphony No.9 in D minor Op.125, 'Choral' : III Adagio molto e cantabile; Daniel Barenboim & Staatskapelle Berlin; from the album “Beethoven : Symphonies Nos 1 - 9 & Overtures” 2004
@24:47 Tchaikovsky, Pyotr Ilyich: Symphony No. 5 in E minor, Op. 64; Bernard Haitink, Royal Concertgebouw Orchestra, Amsterdam, 2012
![The Milky Way [go to 4K edition] go to https://youtu.be/uVxrsJ5lZlQ](/img/1.gif)
Welcome back Mr. Butler. It's been a long time and you've been truly missed.
Always wanted to have a teacher like you or C. Sagan. I guess I’ll have to manage with RUclips.
Too bad the video is so short. Thank you.
If the James Webb telescope ever launches, it would be very interesting to see what it can add to this golden age of astronomy. Thank you for sharing sir.
Superb sir
Any word yet on when UCLA GCG will be releasing their final findings on last summer's closest approach of S-2 ?
It was supposed to come out in November 2018, and here we are 6 months later and still nadda.
This playlist covers that.
@@howfarawayisit You have quite a body of work uploaded, Sir - I look forward to perusing it. Meanwhile, I'd be truly grateful for any direct linkage or citation you might have regarding UCLA's GCG Final Report on S-02's flyby for May 2018 ... not a summary statement for the hoi polloi but the actual report itself. I already looked on their website and youtube pages and found nothing.
Thanks in advance.
@@RovingPunster S2 's pericenter crossing in 2018 was covered by the ESO VLTI. I cover it and how it did it in the full 4K 2019 edition of The Milky Way. UCLA was consulted.
@@howfarawayisit Thanks for the update. Yes, I saw the ESO press release at the time ... I've waiting for the UCLA GCG final report because this has sorta been their proverbial baby from the gitgo, and I was under the impression their data analysis report was going to be the most detailed, exhaustive and definitive one available within the community. Was I mistaken ?
Ghez did a speaking appearance last month, and was also quoted in the recent press releases about the latest composite image of the M87 SMBH, but I saw no mention of their final findings in either article, and there is still no new update on their website, which I find odd.
Thank you again, kind sir.
fascinating. thanks
Thank you.
So it is clear that black hole does not suck any object like star or planets. They only orbit around it.
Second!
Story of my life...
100 Million black holes in our Milky Way Galaxy, and they're invisible. Now this makes me think that even if there were other civilizations in our Galaxy, that they could never travel to Earth, because the odds of them getting sucked into an invisible black hole is too high. Not to mention invisible black holes out there between galaxies. Space... an Extremely dangerous place.
Hard Rock Master. I think space is a dangerous place to travel for many reasons, but not collisions with black holes, stars or planets. The distances between them are enormous and collisions are rare.