Starship Asterisk*

I find that the Picture of the Day is presented in mirror image,
not as actually seen. Is there a reason for this?

Johnski

[quote="JohnD"]Another Q. about that Perseid picture:

These are billed as 'new' stars, but the region is clear of any gas or dust left over from their birth. Pictures of 'star-forming' regions as on the 29th November are dense with cosmic muck!
Does all the gas & dust form planets, or is it blown away by the new stars?

John[/quote]

Based on the distance (7000 ly) of the clusters, all the stars you see in the photo are mostly likely hot and massive young stars. Those stars blow out strong winds and radiation which push out any remaining gas and dust in their natal molecular clouds.

Another Q. about that Perseid picture:

These are billed as 'new' stars, but the region is clear of any gas or dust left over from their birth. Pictures of 'star-forming' regions as on the 29th November are dense with cosmic muck!
Does all the gas & dust form planets, or is it blown away by the new stars?

John

No, they're travelling in different directions more or less randomly, but with some tendency to move about the center of the cluster.

They're not all travelling in the direction of expansion of the universe, but in general, more of them will be heading away from each other than towards each other.

It is possible for two stars to hit each other as you describe, but incredible unlikely. The distance between stars is typically around a million to a billion times their diameter.

I assume you're talking about the Perseus double cluster from today:
http://antwrp.gsfc.nasa.gov/apod/ap071207.html

Iwould like to know if all stars travel in the same direction or can thy hit another star at a high rate of speed head on also are all stars traveling in the direction of the expansion of the universe.