Double Cluster in Perseus - Stars (APOD 07 Dec 2007)

Comments and questions about the APOD on the main view screen.
Post Reply
John128
Asternaut
Posts: 2
Joined: Fri Dec 07, 2007 5:00 pm

Double Cluster in Perseus - Stars (APOD 07 Dec 2007)

Post by John128 » Fri Dec 07, 2007 8:39 pm

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.

User avatar
iamlucky13
Commander
Posts: 515
Joined: Thu May 25, 2006 7:28 pm
Location: Seattle, WA

Post by iamlucky13 » Fri Dec 07, 2007 10:31 pm

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
"Any man whose errors take ten years to correct is quite a man." ~J. Robert Oppenheimer (speaking about Albert Einstein)

User avatar
JohnD
Tea Time, Guv! Cheerio!
Posts: 1580
Joined: Wed Feb 16, 2005 2:11 pm
Location: Lancaster, England

Post by JohnD » Fri Dec 07, 2007 11:05 pm

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

starnut
Science Officer
Posts: 114
Joined: Mon Apr 10, 2006 4:55 am

Post by starnut » Sat Dec 08, 2007 1:37 am

JohnD wrote: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
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.
Fight ignorance!

John Clark
Asternaut
Posts: 1
Joined: Sun Dec 09, 2007 8:07 pm
Location: Scottsdale, AZ

Dec 7, 2007 - Perseus

Post by John Clark » Sun Dec 09, 2007 8:18 pm

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

Johnski

Post Reply