Forming Planets CEA Saclay simulation

New Worlds How long does it take to make a solar system? A. 1 million years. B. 10 million years. C. 100 million years. D. 1 billion years.

Gases in Space Supernova stars explode and create clouds of gas and dust. The gas includes hydrogen, helium, nitrogen, oxygen, etc. Crab Nebula, 1000 years old

Formation of the Sun Stars are formed by a gas/dust cloud contracting due to gravity. Orion Nebula, 1 million years old

Protoplanetary Disk Gases begin to swirl around the star. Inward from gravity Outward from heat Angular momentum is conserved. HR 4796A, 10 million years old

Collisions and Accretion From 10 to 100 million years, dust begins to stick together. This is called accretion, and is aided by gravity. Solid accretion toward star Gas accretion outward Radio image of Epsilon Eridani, 500 million years old

Migration There is more gas and dust near the star for formation. A planet moving outward can slow the spin of a star. Conservation of angular momentum Protoplanet 6 MJ, 2 million years old Keck telescope, 2011

Frost Line The heat of a star melts minerals that are close. Frozen “ices” dominate at greater distances. U Hawaii