Celestial Navigation 101
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- Опубликовано: 16 дек 2023
- This video is of an introductory celestial navigation class I taught at my local sailing center. It covers the history and underlying principles but does not dig too deep into the details. It was recorded on a couple of cellphones, so audio and video quality is not ideal, but I thought it worth uploading for those who could not attend (it was a sold out class)... and as a primer for anyone taking the hands-on class I teach in the spring.
Here are links and other information related to the class:
Some general wayfinding and navigation info:
manoa.hawaii.edu/exploringour...
Polynesian Wayfinding:
hokulea.com/polynesian-wayfin...
theconversation.com/how-far-t...
Mayan Celestial Navigation:
www.cambridge.org/core/journa...
Viking Navigation:
www.vikingeskibsmuseet.dk/en/...
royalsocietypublishing.org/do...
The American Practical Navigator:
msi.nga.mil/Publications/APN
A free nautical almanac:
www.thenauticalalmanac.com/
Some useful navigation apps for your phone:
App: Sextant Stars
From: Sharpitor Elements
A digital equivalent of a Rude Star Idenitifier (sometimes called a 'Rudy'). Helpful for figuring out which stars you are looking at.
App: Stellarium
From: Stellarium Labs L.R.C.
Another app useful for identifying what you see in the night sky. You can change the location and time to see the sky as it would be under those circumstances.
App: Nautical Almanac
From: Capt. Skrypkin M.
Automatic Nautical Almanac lookup and calculation for the sun, moon, planets, and all navigation stars.
App: Sight Reduction
From: Navigation Algorithms
Automates the calculation of azimuth and intercept calculations and draws the resulting lines of position on a map.
If only Mitchel from Australia or for that matter, any flerf should be viewing this video.
I do hope you grasp the enormity of what you have done.
Brian will subject us to a four hour debunk attempt. 🤣
LOL!!
A four hour debunk where not a single fact will be uttered.
Great! Another opportunity to kick Brian around!!!
Flat earthers don't need navigation. They're content to babble at length about how they allege everyone else is doing it wrong.
Very interesting Thad. I'll have to continue the video another day. Watched a good portion of it.
Christmas has arrived a week early.👍
I was tempted to hold off and release this video on the anniversary of the initial 'Response to Tenth Man' video as another Christmas present to that crew... but ultimately this is not really a video aimed at flat earthers, just anyone interested in cel nav... so Merry Christmas! 🙂
Enjoy this PT. Looking forward to Part 2! Thanks.
Hi Petey, Brian's brain cell will have exploded by now!
@@marcg1686 😆
@@marcg1686 debatable if he even had ONE.
Excellent
Thad, the footage at the end, was that from your Baltic cruise?
No, that was a more recent sail on a 29 ft Catalina on Lake Michigan... one of the boats in the sailing center's fleet.
1:12:46 I found it interesting that because GPS can be jammed, the military has computers that identify stars and get their elevation angles for navigation. I'm guessing if they can do that, they can get very accurate position fixes.
It is not even new technology. I think I remember reading an article a while back about the U2 spy plane having something like that.
Great video. Very interesting indeed. I saw your demonstration using a globe to try and educate the flerfs. Is there any merit in doing the same on a Gleason map. Given that some proportion of flerfs think this is the go to flat map. Obviously it wouldn’t work but would certainly show the major issues with that variant of the mystic wafer. Keep up the good work 👍
I've actually done that, and it resulting in the fix being about 450 nautical miles off. I show that about nine and half minutes into my 'Correcting Brian's Logic' video. 😎
@@protothad837 brilliant. I missed that one. Off to watch. 👍
nifty
Timestamp 52:51 you show that the elevation angle measurement of the star is taken from the surface with a horizontal baseline (flat) earth. Then you imagine angles being measured from the center of a sphere. I notice you got your co-altitude from 90°. So you're using that celestial horizon line for your 90° right angle. That's green line is you making it flat. Welcome to flat earth!!!
Look more closely at the image. The green line is clearly not the surface. The surface is that curving thing below the green line. Your claim that a flat surface is needed is just a begging the question fallacy... a flat earth belief you've never put to the test by doing any actual celestial navigation. But I'm still willing to help you with that whenever you decide to move past parroting silly talking points. Who knows... you might actually have fun. It may even change your whole worldview. 🙂👍
It's not begging the question because you used 90° to get the distance on the surface from the ground position of the star. How do you get 90° on a sphere @@protothad837?
@@TB-xx8vj How do we get 90°? It's pretty obvious when you just look at the diagram. The surface is never a line in our angle. The 90 degrees is just the difference between vertical and horizontal. Horizontal is a line projected from our eye. It. Is. Not. The. Surface. Your assumption that the surface is a line in our angle is just a... (drum-roll please)... Begging the Question Fallacy. 😎
@protothad837 The begging the question fallacy is the circle you drew underneath the horizontal plane that you use to get 90° for calculating the distance from the ground position of the star. You have proven that you need a flat earth for celestial navigation.
@@TB-xx8vj _You have proven that you need a flat earth for celestial navigation_
If it also works with the circle underneath, then why are you begging the question by assuming that it's flat?
Latitudes are derived from flat earth elevation angle measurements of Polaris. Welcome to flat earth!!!
There's no such thing as a 'flat earth' elevation angle. Elevation angles are measured relative to horizontal, not the surface. Perhaps you should actually watch the video? 🙂
A horizontal baseline to measure elevation angles of stars is a flat earth. You need a flat earth for latitude on the surface. So it's silly to say the horizontal baseline is not the surface. Similarly, you need a horizontal plane for azimuth angles to get longitude on the surface.
Here's a good question. Why don't they use a globe on ships,@@protothad837? Is it because it doesn't work? 😂
@@TB-xx8vj No, it's just a dumbass question typical of a do nothing incompetent like you.
@@TB-xx8vj Latitude and longitude do not work on a flat earth. The longitude scale always matches the cosine of latitude, getting narrower both north and south of the equator (matching a sphere... not flat surface). This is reflected in every navigation chart, plotting sheet, and the very process of navigation itself. This might become clear to you if you make an effort to set aside your confirmation bias and actually think about what this video is showing you... and especially if you try the process for yourself.
Aha!!
I knew it!
All your previous video's are guilty of Ex Professo Fallacy!!!!!!!!!!!!!!
;-)
/s