Chapter 5: Flashcards
How do nebulas stay together?
Self gravity: the gravitational attraction among all the parts of the same object
How do nebulas create stars and planets?
Where there is a high density of gas, they collapse into stars. The left over stuff creates planets.
What is an interstellar or molecular cloud?
High density region of the space between the stars made up of mostly atomic or molecular hydrogen and dust
What is a nebula?
A cloud of interstellar gas and dust held together with self gravity
How does a protostar become a star?
- Gas in a nebula collects in clumps
- Clumps begin to spin and condense
- gravitational energy converts into thermal energy as the matter becomes more densely packed
-proccess continues through the protostar reaching 10,000 kelvin, where hydrogen fusion happens. Now it’s a star.
What happens to protostars with less than 0.08 the mass of the sun?
They cant reach 10,000 k, so they become brown dwarfs. Not a star, not a planet.
Where do planets form?
In a disk around the protostar called the accretion (collection) disk
What are the 3 determining factors of angular momentum?
- the mass of the object
- the speed of the object’s rotation
- how spread of the object is
What are the jets that a protostar creates?
Left over material that gets blown away form the accretion disk and caught in the wind above the poles of the protostar
What materials are in the accretion disk? Where are they located?
Rocks and metals (everywhere)
Water and Ice (middle and outer edge)
Highly volatile materials, like water, ammonia, and methane (outmost edge)
Why do planets migrate?
Happens through gravitational interactions with other planets.
What are the stages of an atmosphere?
Primary: captured gas during planet formation
Secondary: forms later due to volcanoes, comets which bring water and volatile materials, etc.
