Binary Stars: Visual and Spectroscopic

This is the first of two videos about binary stars and their applications. We learn that there are many types of binary stars, and some of the most important are very near to us. This is part of my complete intro Astronomy class that I taught at Willam Paterson University and CUNY Hunter.

0:00 Introduction
0:01 Apparent Binary Stars
2:31 True Binary Stars
4:28 True Binaries are gravitationally bound.
5:14 Types of True Binaries
6:40 The motion of the star Sirius across the sky
11:52 Measuring Masses
12:49 Why are Visual Binaries so Important?
13:40 Visual Binaries and Masses
14:58 Measuring the Masses of the Stars
16:25 Sirius "B" Mass Measured...
17:55 Spectroscopic Binaries
19:49 Spectroscopic Binary Real Data

[astroab]

Thank you for this amazing astronomy lesson, i just have one small question, how can we make the difference between an eclipsing binary star and a cepheid variable, i mean they both change their brightness, how can astronomers tell one from the other ?

[reemhaidar]

Could you tell me plz what is the simulator you used in showing Sirius motion?