Okay, so it was a partial Moon, but I could see all of the Moon!

[CKemu]

Last night I had my scope set up from around five in the afternoon to let it cool, just around 7:30 I was taking a peak at the Moon - looked gorgeous, but I noticed as my eye's adjusted to the dark that I could see the entire of the Moons surface, despite it being a cresent Moon.

Thought this was a smidge odd, so set up the DSLR, and took some long exposure snaps, obviously the visable cresent was bleached to oblivion, but I could indeed see the entire (visable half) Luna surface!

Is this light bouncing off Earth and hitting the Moon? Did one of you guys decide to shine a blumming large torch at it?

I presume the former, so is this a regular phenomenon, something seasonal and does it have a specific name?

[Ender Of Days]

Yep its Earth Shine,happens every month when you view a thin crescent moon,I got a few pics of it from the other day too ,

JJ..

[Ad Astra]

I noticed that the illumination on the dark portion of the disk was much easier to see when I moved to California than when I was in Illinois (in the center of the USA - 2000 miles from any ocean!).

I think that for a viewer in California, the light reflecting off the Pacific Ocean probably illuminates the Moon better than what little reflects off the Rocky Mtns. and prarie farmland for an observer in the MidWest.

I'm guessing that you may have the same thing in England - and probably a better view of the unilluminated disk than say someone in central Europe.

Dan

[Talitha]

Was it Galileo who first identified the glow as being light reflected back to the Moon from the Earth? I seem to recall reading that somewhere.

[MarySkater]

In the traditional ballad "Sir Patrick Spens," a sailor predicts a storm because:

"I saw the new moon late yestreen

With the old moon in her arm"

I can't say I've noticed it as foretelling bad weather...

Mary

[acey]

I noticed that the illumination on the dark portion of the disk was much easier to see when I moved to California than when I was in Illinois (in the center of the USA - 2000 miles from any ocean!).

I think that for a viewer in California, the light reflecting off the Pacific Ocean probably illuminates the Moon better than what little reflects off the Rocky Mtns. and prarie farmland for an observer in the MidWest.

I'm guessing that you may have the same thing in England - and probably a better view of the unilluminated disk than say someone in central Europe.

Dan

When you consider how far away the Moon is, the view you get from one part of the Earth is going to be almost identical to the view at the same time from any other part (except for a little parallax). If Earthshine is more easily visible in certain places then I'd put it down to local conditions or subjective perception. I do agree that there is great variability in the extent of the effect, but would suggest that background sky brightness (and Moon brightness) is probably the most significant factor. If you've got a low horizon then you have the best chance of seeing the thinnest crescent against the darkest sky, and hence (presumably) the most striking Earthshine. Though if you're viewing from anywhere around the Pacific then I suppose that half of the Earth is going to be more reflective. Clouds must also play a big role.

Edit:

I just checked Wikipedia and found that Earth's oceans are the least reflective part, rather than the other way round.

And it was Leonardo da Vinci who first explained the effect.

http://en.wikipedia.org/wiki/Planetshine

[Talitha]

And it was Leonardo da Vinci who first explained the effect.

Ah yes... thanks!

I had the right country, but the wrong century.

[bombassa]

Nevertheless I think it gives a pretty 3D'ish effect.

[Ad Astra]

Edit:

I just checked Wikipedia and found that Earth's oceans are the least reflective part, rather than the other way round.

And it was Leonardo da Vinci who first explained the effect.

Interesting! I still see the unlit disk much clearer (and more often) than I ever did in the Midwest. Perhaps it is desert skies for the win once again!

Dan