NATS 1740 Chapter Notes - Chapter 14: Large Magellanic Cloud, Cosmic Dust, Spiral Galaxy

• School: York University
• Department: Natural Science
• Course: NATS 1740
• Professor: Randy Hoffman

Document Summary

Our galaxy consists of a flat disk with spiral arms surrounding a central bulge, with a roughly spherical halo surrounding everything. Globular cluster: spherical collection of stars that orbit a galactic core. Interstellar medium: clouds of interstellar gas and dust. 2 small galaxies in the milky way are named large magellanic cloud and small. The milky way is a large galaxy and several small galaxies orbit it. Disk stars orbit the galaxies centre in orderly circles that all go in the same direction, bobbing slightly up and down as they orbit. Orbits of halo and bulge are much less organized than disk. Halo stars swoop high above and below the disk on randomly oriented orbits. Using stellar orbits to measure the mass of the galaxy. We can calculate the mass of the galaxy within the suns orbit using the suns orbital properties and newton"s version of kepler"s third law.