Mastodawn

Corey S Powell Apr 3, 2024

Only three humans have ever witnessed an eclipse of the Sun by the *Earth*. It happened while the Apollo 12 crew was returning home from the Moon, on November 21, 1969.

Fortunately, the astronauts filmed the moment so you can share in the experience.

https://archive.org/details/Apollo1216mmOnboardFilm [at the 4:50 mark] #space #science #nasa #eclipse

APOLLO 12 16MM ONBOARD FILM : NASA/Johnson Space Center : Free Download, Borrow, and Streaming : Internet Archive

Film taken includes a solar eclipse, Charles Conrad and Alan Bean on lunar surface, and scenes of Lunar Module (LM) during lunar orbital rendezvouz and...

Internet Archive

@coreyspowell although I think I see the sun eclipsed by the Earth every night. Not as spectacular at such close range, but I think technically correct.

Corey S Powell Apr 3, 2024

Seeing the complete circle of the Earth is what makes it into a very different type of event, I'd say.

@coreyspowell Oh, yes, but I do think we see an "eclipse of the sun by the earth" when the sun goes down. Just nowhere near as impressive. Even a lunar eclipse can sometimes cover the whole sun (total) and sometimes not quite (annular), leaving a ring, AFAIK. What we don't see, on Earth, is an "annular eclipse" of the Sun by the Earth.

Note the astronaughts did not see an annular eclipse either at that distance.

@coreyspowell Also, surely, if in an aircraft or hot air balloon, looking down, you can see horizon to horizon, complete circle of earth, and do that at sunset or at night?

Corey S Powell Apr 4, 2024

@revk The entire Earth backlit by the Sun, with light streaming through the atmosphere all around the limb? No.

@coreyspowell This "definition" is gradually changing to great a division between people at a certain hight, and the people on, say, the ISS.

Why not specify an angle of view to horizon, or a relative size as viewed?

By a simple dictionary definition, a sunset is an eclipse, sorry. 🙂

"an obscuring of the light from one celestial body by the passage of another between it and the observer or between it and its source of illumination."

Corey S Powell Apr 4, 2024

Show me the dictionary! 😉

@coreyspowell LOL, as I am sure you know, many. None of which have the extra conditions that you can see light around all the edge at once (annual eclipse would be, but astronauts did not see that either).

https://www.merriam-webster.com/dictionary/eclipse

https://www.dictionary.com/browse/eclipse

https://www.collinsdictionary.com/dictionary/english/eclipse (moon/sun specific!)

But to be honest, the view they saw was impressive, none the less.

Definition of ECLIPSE

Definition of 'eclipse' by Merriam-Webster

Corey S Powell Apr 4, 2024

Since this matters so much to you: sunsets are eclipses. Done.

I'm all in favor of having more people pay attention to the beauty of nature. If it helps to tell them that sunsets are actually solar eclipses, I'm all for it.

@coreyspowell OK, sorry, not that it matters any more than mere pedantry, sorry.

And if a sunset is not an eclipse, I have to ponder the technical definition of the necessary altitude where it changes from one to the other, etc, which its more "scientist" than just "pedant"...

🙂

As I say, it looked an awesome video.

Mans R Apr 4, 2024

@revk @coreyspowell I think most people interpret "eclipse" as the casting of a shadow by a planet or moon on another. That excludes people on the ground or in an aircraft. If a dictionary definition allows sunset/night to be called an eclipse, that is probably not intentional.

@mansr @coreyspowell that is an interesting distinction and could work. It would mean the Apollo 12 astronauts would not have seen an eclipse though, in that case, which is what started this discussion.

Steven (but a Goblin) 💚Apr 4, 2024

@revk @mansr @coreyspowell I have to ask, are you guys riffing on today's XKCD on purpose, or is it an accident?

Because if it's on purpose, these are some very funny posts.

https://xkcd.com/2915/

Eclipse Clouds

xkcd

@steven @mansr @coreyspowell and the previous one.

It is also the level of pedantry I’d expect from Randall.

Mans R Apr 4, 2024

@revk @steven @coreyspowell It's all quite simple, really:

☀️ 🌔 🌍 = solar eclipse
☀️ 🌍 🌔 = lunar eclipse
🌍 ☀️ 🌔 = apocalypse

Dan Neuman 🇨🇦

@mansr @revk @steven @coreyspowell If we're lucky it'll look more like
🌍 ☀️ 🌖

No more tides, though, which might mess up the sea life reproduction cycles.