AST 101 Lecture Notes - Lecture 13: Redshift, Annie Jump Cannon, Orbital Velocity
9 Dec 2017
School
Department
Course
Professor
Document Summary
Small explosion on the stellar surface causes nova (novae) The explosion is caused by gas falling from a companion star. A star heats the surface of the second star, temperature increases and a flash is made. All stars in stellar clusters were formed almost at the same time. All of the stars in a cellar cluster have the same age. We know the mass and luminosity (amount of light per second) from the sun. From these numbers a model of the sun was created. For stars you measure the numbers and make models. The brightness of a star depends on distance and luminosity. Total amount of power the star radiates in space. Divide the luminosity by the area of a sphere to get brightness, As you move away from stars their brightness gets lowe. To calculate luminosity from brightness you need the distance. Shift of position in an object against a background of more objects.
