Starship Asterisk*

Chris-- Reference? I am a bit doubtful. In any case not statistically or geologically meaningful, because ALL rocks, of any origin, become much scarcer with time, due to plate tectonics and erosion. The smaller and younger craters, which are heavily over-represented in the "confirmed" cate...

Manicouagan is not even close to being one of the oldest craters. Actually relatively young. Over 95% of the earth's history had already passed by the time it formed.

Although it is perhaps reasonable to call these "cliffs", they don't appear to be sheer cliffs (vertical, near vertical and/or overhanging). So I'm skeptical about the free fall references. Would guess given the low gravity these might be ski-able. Earth analogue is exposed normal fault sc...

Um, we do know many of the processes involved. We know the temperatures (low), the pressures (low), and to some extend the materials, (generally icy), we know the gravitational forces. And we know that the forces and chemistries are not fundamentally different than those on earth (at least in labs)....

AKA Messier's Nightmare.

trunkfish

they can change their spots, as this is going to do over time.

Also, the impact is not really "oddly colored". The interior of the crater seems quite similar to the areas near the limb of the moon in this image. Rather more interesting are the thick layer of light material exposed in the upper walls of the crater, and the prominent dark layer exposed ...

It would take a MUCH larger impact to "destroy" Mimas. 4 Vesta has a crater nearly its own diameter, and the Earth (now the Earth-moon system) seems to have survived a Mars-size impactor quite nicely. To destroy such a large body, you need to inject enough energy that at least a majority o...

The idea that galaxy mergers result in elliptical galaxies is challenged by this study:

http://www.sciencedaily.com/releases/20 ... 101719.htm

In this case there is so much gas and dust involved a merger would seem to guarantee a spiral.

Mars flexes his biceps.

So cold results in forearm fracture.

Oh well, the tats look great...

Say what? 22 million light years is not "far beyond" the local group.
Only ten times as distant as M31.
By comparison, if the Milky Way-Andromeda distance were scaled down to the radius of the earth's orbit about the sun, NGC3621 would lie halfway between Jupiter and Saturn.

Beautiful sunset. We're (except the pilots/frequent fliers?) just not used to looking DOWN on sunsets. I once descended into a sunset and it was unforgettable The broken cloudtops were almost black and the undersides of the clouds (seen through the numerous gaps), formed a network of brilliant red a...

"Tiger stripe" is a colorful but useless term. The prominent feature in this photo is a rift valley. To the right side of the picture it passes into a triangular region and thence into two symmetrical deformed belts at approximately 120 degrees to the rift trend. Although the symmetry of t...

Yeah, fake was not a good choice of word. I was merely curious whether the image was obtained as you describe (a composite), or whether it is possible to achieve this with a single exposure (short, to avoid streaking of the stars or foreground). In either case it is very well done. I'm not saying th...

There are no volcanic rocks in this picture!!! These buttes are composed of sandstone and mudstone. They are erosional remnants--quite unusual to be sure, but obviously stratigraphically continuous with the adjacent mesa. Another minor peeve: either this picture is quite cleverly done with high spee...