# Thread: Mass of the solar nebula

1. ## Mass of the solar nebula

Can anyone point me to an article that gives an accurate value for the mass of the initial solar nebula? I've looked, but all I can find are values less than the mass of the Sun, which seems impossible. Am I missing something?

2. That seems impossible to me too-- there's no new mass being added. There is matter being lost, as there is a need to carry off angular momentum in order to be able to form a star. But after that process has gone on long enough to yield something you would call a star, then there's very little matter outside of the Sun-- so the mass of the solar nebula is pretty much the mass of the Sun, from then on. Are you asking what fraction of the mass must be carried off with the angular momentum? That's a frontier research question.

3. ## Could be anything

Originally Posted by parallaxicality
I've looked, but all I can find are values less than the mass of the Sun, which seems impossible.
That's because "solar nebula" is jargon for "everything that is left over after the sun is formed". The "solar nebula" is the part left over, from which the planets form. It is generally thought to be no less than about 0.1 solar masses (i.e., Weidenschilling, 1977; Ruzmaikina, Khatuncev & Konkina, 1993).

If you want the mass of the pre-solar nebula, out of which the sun & solar system formed, you are out of luck. There is no way to even guess what that would be, since we have no way of pinning down the pre-solar environment. Stars form when condensations occur in molecular clouds. The clouds can hold hundreds or even thousands of solar masses of gas & dust. Does the sun form alone, from a single glob, or does it form in a cluster? If it forms in a single glob, the minimum mass would be about 1.1 solar masses, the sun plus the solar nebula above. If it formed in a cluster, it could be anything.

4. Thank you. That doesn't make my job any easier, but it does make things clearer. Are you aware of any articles that make this distinction clear?

5. Originally Posted by parallaxicality
Thank you. That doesn't make my job any easier, but it does make things clearer. Are you aware of any articles that make this distinction clear?
You might like this article (Jeff Hester) demonstrating evidence that puts the sun in the big cloud scenario.

6. Thank you! It certainly livens up the story a bit :-)

7. Originally Posted by parallaxicality
Thank you! It certainly livens up the story a bit :-)
Indeed. We are all made of stardust, probably that one!

8. OK, so could someone who actually knows what they're talking about, (ie, not me) please tell me if this article, (the "Formation" section) makes sense, or is just a rambling mess?

http://en.wikipedia.org/wiki/Solar_System

9. I also would like to know.

However, it seems to match what little I have read. If it weren't late and after a long day, I would look-up aggregation. I want to say the article is describing aggregation.

I do recall reading how the fine dust and gas particles will grow into chondrules(?). Gas and dust have solar pressures working on them so their orbital speeds are not Kepleraian. This is important as when the particles reach a certain size, and probably dependent upon distance also, they begin to migrate inward. I suspect, and hope someone will confirm, that it is because the mass of these growing particles increase as the cube and their surface area as the square. So, as the particles grow the ratio of the solar pressure to their mass diminishes and they will migrate as they become more susceptible to Kepler motion.

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