How Big Was the Interstellar Cloud From Which Our Sun Formed?

-- Frank | April 7, 2020


Hi, I was wondering, what would be the estimated size of an interstellar cloud required to produce a sun-like star? Comparably speaking, how far from the sun’s current spot into and through the solar system might the cloud stretch?

-- Frank


The giant molecular clouds from which stars form tend to have masses of about 10^4 solar masses of gas and dust that has a size of approximately 50 parsecs.  Through a very slow process of gravitational collapse and fragmentation, this molecular cloud fragments into clumps that are about 0.1 parsecs in size and have masses in the range of about 10 to 50 solar masses.  Over a period of about 10 million years, these molecular cloud clumps form stars.  Since the original giant molecular cloud fragmented into molecular cloud cores, leading to the formation of many stars, one could say that the formation of our Sun derived from a molecular cloud fragment from this giant molecular cloud.

-- Jeff Mangum