Proper Motion and Parallax

This is part of my complete intro Astronomy class that I taught at Willam Paterson University and CUNY Hunter. If you want to watch all the videos in the correct order, please visit my website at http://www.jasonkendall.com

The stars move in many ways. They are not fixed in the sky but changes slowly over the centuries.

Supplement the videos with "OpenStax Astronomy"
https://openstax.org/books/astronomy/...
3.3: Newton's Universal Law of Gravitation

https://openstax.org/books/astronomy/...
17: Analyzing Starlight

https://openstax.org/books/astronomy/...
18: The Stars, a Celestial Census

https://openstax.org/books/astronomy/...
19: Celestial Distances

https://en.wikipedia.org/wiki/Proper_...
Proper Motion

https://en.wikipedia.org/wiki/Radial_...
Radial Velocity

https://en.wikipedia.org/wiki/Stellar...
Space Velocity

https://en.wikipedia.org/wiki/Parallax
Parallax

https://en.wikipedia.org/wiki/Barnard...
Barnard's Star

https://en.wikipedia.org/wiki/Hyades_...)
The Hyades

https://en.wikipedia.org/wiki/Galaxy_...
Dark Matter from Galaxy Rotation Curves

http://schmidling.com/barnard.htm
Jack Schmidling's view of Barnard's Star

http://mentallandscape.com/V_RadarMap...
Radar Mapping of Venus

0:00 Introduction
2:33 Stellar Parallax
3:58 A star at a far distance
4:27 Parallax is defined to be half of the total shift
4:43 The definition of parallax distance
5:39 The Phases of Venus and the Distance to the Sun
7:26 Parsec Definition
10:14 Proper Motion: Stars moving across the sky
13:05 Proper Motion of the Hyades
15:41 Proper motions are cumulative
17:46 Case Study: Proper motions in the Big Dipper
19:52 Proper Motion depends on the Distance
21:10 Radial Velocity
24:03 True Space Motions
26:37 Why measure the space motions?