CAS AS 102 Lecture Notes - Protostar, Bipolar Outflow, Low Mass
Document Summary
Interstellar medium: this is the place where stars are formed. 1% of the ism material is in what we call interstellar dust. Dust is iron, silicon, carbon, start to stick together in cold, dense regions. It has to be a cold region so that they move slowly and gravity can make them stick together. Dust blocks light from stars, galaxies, etc. , this is called interstellar extinction. Certain wavelengths of light will interact with the dust in ism. Short wavelengths will suffer heavily from interstellar extinction. Cool red giant stars have a lot of dust around them. Interstellar reddening is when we think that a star is redder than it actually is because of the way that dust distorts the light from stars. Dust has its own emissions from 10-300k and emits in infrared. The ism is not uniform everywhere, not the same temperature or density. The ism has three types of gases: hot gas, cold gas, and warm gas.