Starship Asterisk*

Why oh why do astronomers insist on mispronouncing the Greek alphabet? It is not letter Nu, nor Mu. It's Ni and Mi (pronounced 'nee' and 'mee' as in the English words see, fee or bee). And by the way, Pi is also pronounced 'pee', as in... pee, not 'paï' as in pie - but fine I guess it's too late to ...

That spacecraft that flew close enough to the nucleous of a comet - I'm terrible with names but you know what I mean - discovered that it is more of a dirty snowball than a snowy dirtball - or was it the other way round? Anywho, if such a snowball was ever to collide with us, would we be in any dang...

Still, 7,000 light years across is a very very extremely huge place.
/NGC 6822 slaps impudent humans, who ya calling a dorf?

emanating from the central stars, visible in the center

I don't see any stars. Only a weird whiteish thing with a black centre.

Very interesting Bruce, especially your second hypothesis, i wouldn't have thought of that. Maybe one of the scientists can say if electromagnetism could be at play here? My very first thought when I saw this perfect egg shape in the picture and read "3 km diameter" was 'snowball'; Methone...

I am a bit puzzled. If this picture shows galaxies as they were 13 billion years ago, I would expect to see mostly irregular and/or spiral galaxies. 13 billion yrs ago and, already, plenty of oval-shaped galaxies where it seems star formation has already ceaced? Weird.

Anthony Barreiro wrote: And, come to think of it, is it a malapropism to talk about the geometry of an object 700 light years from Earth? Good point! I haven't googled it, but I think that "geometry" means "geo" + "metry" which might mean "Earth" + "meas...

Will we be able to continue receiving a signal from V1 even if/when it enters the heliosphere of a different star? (not very soon of course but it's bound to happen sometime, right?)
What information are we getting from V1 about the areas it's going through?

Many thanks for all this info Chris! Yes, I see now, the two bodies might have started with the same elemental 'heritage' billions of years ago but, you're right, without wind erosion, oxidation, or all sorts of mineralisation resulting from the presence of water, the Moon ended up looking quite dif...

A few questions I always wanted to ask about the Moon: Why is the moon so uniformly grey? In all the colour pictures I've seen of the moon (I can tell they are colour because e.g. of the astronauts' spacesuits) there isn't the slightest fleck of colour, ever. It looks like it's 100% made of concrete...

Ashes to ashes and dust to dust. It's the END of the world!, at the end of the world. Has any lightning been seen in the going's on out beyond our solar system, or is it just too small to be seen that far away?? We can expect lightning occuring only on planets, or large moons with their own atmosph...

That's an awesome picture. I feel so lucky that I live in an era that human technology lets us glimpse such wonders from gazillion miles away. I still regret though that the Huygens probe wasn't programmed to survive a bit longer than just the descent to Titan. After a voyage that took years and yea...

What will happen to the stars in the tidal tail? Are they forever lost in space? Are they going to form a blob "galaxy" that people on APOD will mock?

Wow Thanks Ann. I, I got a bit misty eyed there towards the end. Come to think of it, I always wondered, are there stars out there that "lost" their galaxy, stranded in the whatsimacallit, intergalactic medium i suppose? I've seen pictures of galaxies torn apart from gravitational encounte...

Beyond taking in the awesome photos posted each day, one of my favorite things about APOD is sharing it with my friends that don't care too much about science. With that said, I do wish that there was a "dumbed down" version of the text - no one ever reads it because they get confused and...

solseed.eric wrote: "We may think that ice forests are a laughable idea now but life will find a way to make them eventually and then vacuum forests and then the huge surface area of the outer icy worlds of Sol will be open to them." I very much doubt this. The only way there would be what...

My guess is when the solar system was still very young, the Earth collided with a third body the size of that ball - which I expect would make for a tremendous collision - that a) broke off a huge chunk of it and created our moon and b) was mostly water ice (like some moons of Jupiter or Saturn) whi...

Your site is totally awesome. I can't say whether the images or the caption is more important, they compliment each other. And they are both of such impeccable quality. Proof, I have been visiting APOD since 1998; I start the day with it (and a cup of coffee); almost all my desktop images are from A...

It's like seeing an hourglass from below.

When I first saw the photo, I thought the large stone would turn out to be a meteorite or something, but no.
Ok, it's a regular stone on a muddy field. Has anyone actually seen it slide when it rains?

So I was checking out the link about registering supernovae and I saw a post there about the correct way to write supernova in plural. Before I go any further, let me say here that I strongly support and admire science and in particular astronomy. But there is something that has been bothering me li...

If the origin of the nebula was two white dwarf stars spiraling into each other and exploding leaving nothing (or nothing visible) behind, shouldn't then the nebula have a more elaborate shape, say, like the cat's eye nebula?
This one is round like an orange!

That galaxy in front must be really enormous, and it doesn't seem to have any dust and looks quite reddish. It looks as if there is no new star formation going on and all the stars are super old. What do you say is to happen to such a big galaxy populated by Betelgeuse-like stars? How is it going to...

Thanks neufer! This is one strange nebula.
So, if I understand correctly, the initial hypothesis of a binary system was based on the observation of both silicates and PAHs in NGC 6302?

In the caption under the other photo of the Butterfly Nebula (APOD 2 June 1998) it said NGC 6302 is a binary star system. Where is/what happened to the other star?

Also, NGC 6302 reminds me of Eta Carinae.