Starship Asterisk*

You're looking at a close-up; in fact a little piece of the pelican. To see the pelican follow the "Pelican Nebula" link. I think we're seeing the top of its head, but in a different kind of view.

Very nice APOD.

So may we infer the brighter parts are moving toward us?

After posting that comment it occurred to me the Sun is probably the strongest broadcaster in the area on those wavelengths also, so maybe the bright area is pointed toward the Sun, and it really is a shadow situation.

Ok, this is a "radar image". Presumably it's made from the waves sent from point R to asteroid A and which bounced back to point R. But it sure looks like the "light" source is to one side and the other side is in shadow. What's going on here?

It's Nov. 5, 10 am ET and no new APOD. I hope there's no serious problem. In my experience this is very unusual.

I love this. It blows up really well.

I'm guessing that bubble-like galaxy(?) in the upper right is known and has probably been an APOD subject in the past.

Very nice APOD.

As I understand it there are competing hypotheses about the "waterfall" itself, one holding that it's a shock wave, which presumably would over time manifest itself more toward the top and right of where we see it now, and the other hypothesis holding that it's a jet, likely moving out fro...

What created the Waterfall Nebula? No one knows. You might consider saying instead, "We don't know." Else you are speaking for all persons, which is patently absurd, and smacks of pontification. If the APOD folks say "no one knows" something about astronomy there's a good chance...

Another great APOD. Visually striking and educational.

I'm surprised at Ganymede's position in relation to Io, and also in relation to the banding of Jupiter. We apparently see Jupiter so that its equator is "in the middle" - that is, the horizontal bands on Jupter or not seen to form any kinds of "arcs". But Ganymede appears to be ...

Another great APOD. Thanks again everyone involved.

Great image, great APOD. Does anyone know what fraction of the sunlight the rings actually block from Saturn in, e.g. the season we're viewing? I'm thinking they could really complexify the atmospheric dynamics if there are those giant areas of real shadow that move slowly over the hemisphere. In th...

Very nice.

I'm with alter-ego and OrionEridanus. Fun to look at and conjecture on but I also don't see the big deal.

But, just for the record, let me be the first to mention Cthulu.

I also thought Mercury was tidally locked Orin, but according to the Wikipedia article they did radar observations in 1965 that disproved that. I suspect you and I read some of the same pre-'65 Sci Fi. I found the animation to illustrate a Solar day very confusing. Partly I blame my lack of coffee, ...

Earth’s Oceans: A Cometary Source After All? Getting water into the inner Solar System is an interesting exercise. There has to be a mechanism for it, because the early Earth formed at temperatures that would have caused any available water to have evaporated. Scientists have long speculated that w...

I'm guessing with the M81 encounter and its results that became a tough place to live, what with all the supernovae and their radiation. And of course such a future lies in store for the Milky Way (M0?) when Andromeda flies by in a while. Exciting times. Nice APOD. neufer, let's consider an alien ra...

Thus are religions founded. One event then another and it's (too) natural to assume causation. If there was video going around of a CME followed by a comet there'd be a few people thinking CME's cause comets.

Nice pic. The link from yesterday's APOD to today's doesn't work and on yesterday's there's something about an astronomy picture of the week I was not allowed to access.

I'm having a problem with the link from the Discussion back to the APOD.

This is a wonderful APOD. One of my favorites for sure!

Ann, once again a relevant and informative reply. Thank you.

Area scales as the square of radius or diameter (in general, length) so if the diameter of the sun is 100 times earth's, the area is 10,000 times earth's.

I looked at that and immediately thought The Scream.

Yet another great APOD.

Beware of kooky ideas expressed with certainty, in astronomy as well as politics.

Another great APOD. And what's with that Richat Structure, anyway?

Again, very nice image and a great APOD.