Physics and Python stuff. Most of the videos here are either adapted from class lectures or solving physics problems. I really like to use numerical calculations without all the fancy programming ...

So now you have an Earth-Sun-moon model. You can try changing some of the parameters to see what happens. If you like, could modify the program to include the motion of the Sun due to the ...

If you need to re-run this model (in python), just click the "play button." In this model, both the Earth and Mars orbit a sun—please realize that this model is not to scale.

NASA’s Solar Dynamics Observatory captured this image of Earth and the moon transiting the sun together on Sept. 13, 2015. The edge of Earth, visible near the top of the frame, appears fuzzy ...