Video Analysis of the SpaceX Crewed Dragon Launch

It’s kind of a big deal. SpaceX launched the crewed Dragon 2 into orbit and dock with the International Space Station. Here are two important facts to put this in perspective. SpaceX was founded in 2002 and had their first rocket to reach orbit in 2008 (the Falcon 1). There has not been a crewed spacecraft from the USA since 2011 when the space shuttle Atlantis launched.

So, how do you celebrate an event like this? Some people might write a song or draw a picture — -but I like to do some physics. That’s exactly what I’m going to do. How about a video analysis of the launch to estimate the acceleration of the rocket. Yup. Let’s get to it.

Oh, you missed the launch? Here it is.

The first part of the launch is the best to use for a video analysis. The goal here is to get the vertical position of the spacecraft as a function of time. To do that, I am going to use Tracker Video Analysis (free software and awesome) to mark the location of the rocket in each frame of the video. However, since the camera is also moving (and zooming) I will need some reference point to determine the correlation between pixels in the video and real distances. There is that nice launch tower, but once the rocket gets too far above that there…