Starship Asterisk*

Good Morning. Many of the craters seem to have a little "hill" in the middle of them. Is this a usual effect when some debris hits the surface? Yes it is, if the impact is forceful enough. If you can, try looking at the (our) moon through a small telescope or even binoculars and you will ...

To the question raised by Guest and others wondering about why the leading face of a tidally locked moon will have more craters than the trailing face an analogy might be of help. Think of a vehicle driving through rain. Some raindrops will hit the rear window, but many more will hit the front winds...

Not impossible perhaps but it seems to me that if there was a binary SMBH here then this entire galactic core area would be much more active than what is presently observed.

But, what do YOU, think Bruce? Convincing evidence (a large number of stars very rapidly orbiting something that’s so dim we can’t see it) leads this Bruce to believe in the existence of the Milky Way’s central Super-Massive Black Hole... Hi, other Bruce. I think it's likely that there's something ...

Assuming that they're real, and I agree Chris, they almost certainly are, Why Is todays APOD entitled "THE Black Hole in the Milky Way" since there are likely many BH's of various masses in our galaxy. Nit picking, but it would have been more correct to have added either Central, Super-Mas...

Having read the Wikedpedia entry and noting this... {Chapline} proposed that objects currently thought to be black holes are actually dark-energy stars. This idea incorporates the 1980 proposal by Robert B. Laughlin and Chapline that the surface of a dark energy star actually represents a quantum c...

However, I am open to improved explanations Bruce. Having just read your link I see that your source ain't no dummy.

An open minded Bruce

Some people -- e.g. http://en.wikipedia.org/wiki/George_Chapline -- have suggested that black holes might not exist. But, what do YOU, think Bruce? Convincing evidence (a large number of stars very rapidly orbiting something that’s so dim we can’t see it) leads this Bruce to believe in the existenc...

Now, that's a REAL blue dwarf. To avoid confussion and consternation in my unimportant opinion this term should be reserved for blue stars in the broader "white dwarf" sequence.

Bruce

Say, wheren't there similar looking troughs on Vesta?

Bruce

Looking at the full image - in the area around pixel location 1997,1652 - there's something curious, at least to my eye. Zoomed in, it's about 5 pixels (35 ish meters) across, and very sharply demarked. The obvious answer is that it's a small upthrust of some kind, or a large loose boulder - but to...

The striations running across the moon appear in many instances to be joining lines of impact crators. This especially noticable top right. Also perhaps emanating from the mjar right crator. Could this be like an "atmospheric" erosion where the atmosphere is something really erosive like ...

Does anyone else see the face-like appearance of the light blue nebulosity to the left of the bright nebula? I see a prominent nose, a puffy cheek, a pink hued eye socket, an ear and a trailing mane of hair, making it look like someone holding their breath against an underwater current.

Bruce

Ah, a little nuclear astrophysics for breakfast! Yum. Thanks Ann. The terminology won’t kill me but it does tick me off, and as I read through your delightful post I got even more steamed. :x So even stars like Achernar are dwarves!? (dwarfs? Which is correct? I’ve read scientific papers where the l...

In reality, the Sun is white. Ann I thought the Sun is actually green. So, what does this make the sun really, a white dwarf??? or a green dwarf??? Really now, why should a middle of the main sequence middle aged star be called a dwarf simply because it's smaller than over the hill bloated behemoth...

Thanks for the more complete explanation.

Bruce

Ann wrote: "The fascinating whitish shapes at right suggest low-mass star formation to me." I don't know about the mass of the stars involved but there is star formation going on there, as discussed in the last link in the Expanation. What draws my eye about this apod is the extremely dark...

Tsap wrote:shouldn't dust make light more red than blue?

Dust would, but not gas. Think of how a moonrise after a windy, dusty day (at least here in dry Texas) makes the moon look red, but with a clean sky it looks normal.

Ann, thank you sincerely for pointing out the comparison between Andromeda and M101 (the Whirlpool Galaxy?). What a dramatic contrast! So, what I thought of as evidence of a great deal of new star formation along Andromeda's rim was nothing compared to other galaxies. Very instructive. Am I correct ...

Yes indeed Anthony. This is a truly stunning image. One of the things I find a bit surprising about this is how much new construction is going on out in the 'burbs, of our galactic neighbor. There must be a lot of gas out along the rim of Andromeda to supply all these active star forming regions suc...

What would a version of this picture look like if everything < 12.5 billion years old was removed? Good question kimmeyh. I would imagine that the larger and brighter galaxies would be filtered out, but the great majority of the faint fuzzies would still be there, and those make up the large majori...

http://imgsrc.hubblesite.org/hu/db/images/hs-2012-37-c-web.jpg This image compares the angular size of the XDF field to the angular size of the full Moon. The XDF is a very small fraction of sky area, but it provides a "core sample" of the heavens by penetrating deep into space over a sig...

The danger from a black hole depends upon both it's mass and your distance from it. I think that a safe distance from a 150 solar mass black hole would be an unsafe distance from a supernova. Absolutely true. We'd be perfectly safe right here on Earth (or even on Venus) if the Sun were a 150 solar ...

The danger from a black hole depends upon both it's mass and your distance from it. I think that a safe distance from a 150 solar mass black hole would be an unsafe distance from a supernova.

Bruce

After thinking about this Black Hole in Orion idea and discussing it with others to the point of having my intial skepticism (which was exactly like Ann's reaction at first) melted away I submitted a post on another blog and called it "The Goldilocks Princple": Ok, so let’s assume that thi...