Star formation

Definition

Star formation is the process by which dense regions within molecular clouds in interstellar space collapse to form stars. This often results in the creation of a cluster of stars rather than a single star.

5 Must Know Facts For Your Next Test

1. Stars form in molecular clouds, often called stellar nurseries.
2. The process of star formation typically begins with the gravitational collapse of a region within a molecular cloud.
3. Protostars are early-stage stars that form before nuclear fusion begins.
4. The Jeans instability criterion determines whether a region within a cloud will begin to collapse under its own gravity.
5. Star formation is often accompanied by the formation of protoplanetary disks, which can eventually lead to planet formation.

Review Questions

• What triggers the gravitational collapse in molecular clouds leading to star formation?
• What is a protostar and how does it differ from a main-sequence star?
• Explain the concept of Jeans instability and its significance in star formation.

Related terms

Molecular Cloud:

Large, cold regions of gas and dust where new stars are born

Protostar:

A young star still in the process of forming, before nuclear fusion starts

Protoplanetary Disk:

A rotating disk of dense gas surrounding a newly formed star, from which planets may eventually form