Starship Asterisk*

Presumably, the Earth was subjected to the same "heavy bombardment" as the moon. Is is generally believed that (with some notable exceptions) evidence of this bombardment has been mostly washed away by our oceans, or what?

Never mind . . . got it now (the inset). It was just late arriving. Sorry!

I'm not getting the promised inset when I run my cursor over the image; anybody else experiencing this problem? Thanks.

Can anyone say whether the apparently linear "spokes" seen in the movie are real phenomena or simply artifacts of the way in which the images were processed?

If, as some might suggest, "the flow of time" is viewed as being nothing more and nothing less than the evolution of the physical universe (an evolution governed by rules which we strive to understand and which we refer to as the laws of physics), then is it possible for there *not* to be ...

Wow . . . that's a lot of salt!

I'm puzzled by the surface of the jetty. Water, even briny water, typically isn't lumpy. So is the substance on the surface of the jetty snow? In August? If not snow, then what?

An administrative question: why isn't the APOD for 14 November 2010 listed in the APOD archive? It still wasn't listed as of mid-day on 15 November.

I seem to recall reading somewhere in the dim past that low-level nuclear reactions continue to occur in the Earth's core, and that these reactions are part of what keeps the core warm. Is that not correct? The explanation which accompanies today's apod suggests that it is not correct.

Congratulations! Checking APOD is how I start my day. It puts my world into a useful perspective, helping me to better assess the importance of day-to-day issues relative to the grander scheme of things in the universe. Thank you and best wishes for many more great years!

An excellent, logical, understandable answer to the question of rotation . . . thank you! It makes perfect sense when seen this way. This also apparently explains why some stars (is it neutron stars?) rotate at unimaginably/unbelievably high rates . . . many rpm's?

Thank you for your helpful replies to my earlier question. Now, other questions which spring to mind are why do stars rotate at all, and why do some rotate faster than others? Seems quite odd. What spins them up?

How do we determine the rotation rate of stars (or even the fact that they rotate at all)? I can understand how we might do this for our sun by observing sun spots or other solar phenomena having a temporal duration, but how do we do it for more distant stars?

Hi jackbunny, Welcome to the APOD discussion forum! Sorry no one has gotten back to you sooner. Usually the more experienced "old hands" here (of whom I'm personally not really one, yet) typically reply to questions such as yours (and mine) on a timely basis. The reason I hadn't replied so...

Many thanks for the helpful replies!

http://apod.nasa.gov/apod/ap091201.html Apparently not being quite as serious a reader as the exemplar depicted in the link in the caption to the Veil Nebula APOD, I have not been able to identify the filaments in the lower left of the image. Can anyone please help? If so, I might be persuaded to gi...

Wow. I'd like to thank everybody who responded to my question for providing such helpful, informative replies, and for expanding the scope of the discussion in such interesting ways! Cheers to all!
Smitty

It appears to be pretty well accepted that there are black holes at the center of many spiral galaxies, but does anybody know (or has there been educated speculation about) what is at the center of a typical globular cluster? Is it a black hole? Other? And while I'm asking, are there any known reaso...

I expect it may be some sort of catalog labeling for the advanced alien race that is monitoring our progress on earth. :wink: Another friend suggested perhaps it was done by Superman during his rebellious, teenage years. Perhaps his version of carving his initials into a tree trunk? Super vandalism...

Ooooops! Please make that "visible in two out of the four images"! In addition to not having been near the moon that day I also wasn't near a math class. I don't feel so bad, however, knowing that four out of every three people are confused by fractions.

Has anyone else noticed the large, clear, prominent letter "S" stamped on our moon? It's clearly visible in two of the three images in the apod for 3 September. Guess that would be on the side facing away from earth? Hmmmm . . . the speculative mind could have a lot of fun with this! Of co...

You're correct about the interesting information, iamlucky13. Very educational as well as beautiful.

I only see it on the perimeter of the larger enhanced photo. Like maybe it is the edge of the photo.

Orin

The seam runs vertically up and down the image about 3/4 ths of the way across from the left. It can be seen in the "disconnects" of the star "spikes."

Smitty

The wonderful folks who put our beautiful APODs together typically do such a fantastic job that we seldom realize that they're probably often assembled from different parts. The slightly noticeable "seam" in today's photo, (6 Aug '08, NGC 1818: A young Globular Cluster), is just a little r...

Yikes! Frogs in Space! A race of hungry amphibians roaming through intergalactic space looking for water and food rich planets to plunder. If this doesn't unify the inhabitants of planet earth, what will? Defenders, set your phasers to stun!