NavList:

It's something of an illusion. Although it certainly looks like the very brief "diamond ring" phase of an earth-based observer's solar eclipse, a lunar astronaut's solar eclipse should look like this for the entire duration of the eclipse, up to a couple of hours --and it's usually exceeedingly bright. The Sun's light refracts and scatters and makes an "Earth Ring". That's well understood. 

It's not so obvious that this Earth Ring is bright like a burning strip of magnesium (*) and stays that way through the duration of the eclipse. The Earth Ring would have a total apparent magnitude, even when the Sun is fully, deep behind the Earth, of about -15.5 (at brightest, somewhat lower under varying conditions). For comparison the Full Moon (not eclipsed) is around magnitude -12.5, but unlike the Full Moon, the brilliance of the Earth Ring is confined to a narrow sliver about half a minute of arc thick at most --just the apparent depth of the Earth's sensible atmospher as seen from the Moon. This is bright enough that I offer this prediction: the first "Moon tourists" who have the pleasure of watching a "solar eclipse" from the Moon (seen from the Earth as a lunar eclipse) will suffer some eye damage, though with any luck it would be temporary.

Rafael: maybe you would know? Do you think a thin strip of light like the dazzling-bright Earth Ring could do anything more than create annoying after-images? Of course, Moon tourists would necessarily be observing through glass, either through "space helmets" or through a window on some "habitat" station. That could be tinted, too.

Incidentally, there are images of the "solar eclipse" seen from the Moon and photographed (tv images?) by Surveyor 3 in April 1967. Although the image quality is lower, the overall appearance is quite similar to the new images from the Blue Ghost lander. 

I learned a couple of days ago, via a small note on the wiki page quoting an earlier APOD page, that these images from 1967 were re-discovered in the NASA image archives following inquiries by someone that I know personally, Russel Sampson, astronomer (now retired) at Eastern Connecticut State University. I emailed him yesterday, and he filled me in on some background... More than a decade ago Russ Sampson persuaded a NASA image archivist to dig these up, and Sampson assembled the frames into a brief animation which is now found online as a short "GIF" sequence. And how do I personally know Russell Sampson? He attended several of my celestial navigation workshops at Mystic Seaport about ten years ago, including my "Lunars" workshop. It's always "lunars", isn't it? :)

Frank Reed
* Not literally as bright as burning magnesium, but "like" that: a very thin strip of brilliant light.