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Nebula and star formation

by Sastronaut
Tags: formation, nebula, star
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Sastronaut
#1
Mar24-14, 04:24 PM
P: 66
Would you expect to find stars being made more easily in a cool, high-dense nebula or conversely a hot, high-dense nebula? Looking at for example the pillars of creation which is a stellar nursery, but what would be classified as hot and cold? relatively speaking. thoughts? thanks pf!
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Damo ET
#2
Mar25-14, 06:27 AM
P: 89
Cold nebula. It is far easier for gravity to do its thing when the gases are cool. I am not sure of the temperatures off the top of my head.


Damo
Cosmobrain
#3
Mar25-14, 07:05 AM
P: 66
On the other hand, if the cloud is hot, it is gonna take less time for the star to ignite because it already has some temperature. However, I don't think that temperature wold be significant.

cb

D H
#4
Mar25-14, 08:13 AM
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Nebula and star formation

Temperature is very significant. Stars don't form from hot clouds. They form from cold molecular clouds, with temperatures less than 20K or so.
Cosmobrain
#5
Mar25-14, 11:22 AM
P: 66
Quote Quote by D H View Post
Temperature is very significant. Stars don't form from hot clouds. They form from cold molecular clouds, with temperatures less than 20K or so.
How can a temperature of only 20K be significant? How can it disturb the formation of a star? Just wondering?

thanks, cb
Drakkith
#6
Mar25-14, 04:28 PM
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Quote Quote by Cosmobrain View Post
How can a temperature of only 20K be significant? How can it disturb the formation of a star? Just wondering?

thanks, cb
Hotter clouds resist gravity since the temperature determines the outward pressure the gas will have. During the initial collapse of the cloud, when it is still a long way off from forming a star, it needs to be very cold in order for gravity to bring it together. Remember that the density of these gas clouds is still very very low, as is the gravitational force the cloud exerts on itself.
Sastronaut
#7
Mar26-14, 09:12 AM
P: 66
Okay so cool/dense cloud for the star, but when you have proto-star forming and the gas around it is heating up...would that hot gas/dense then be more beneficial for proto-planet development?
Drakkith
#8
Mar26-14, 06:09 PM
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Quote Quote by Sastronaut View Post
Okay so cool/dense cloud for the star, but when you have proto-star forming and the gas around it is heating up...would that hot gas/dense then be more beneficial for proto-planet development?
I think that depends on what you mean by "beneficial".
Sastronaut
#9
Mar31-14, 02:04 PM
P: 66
your right that is relative drakkith


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