Jupiter Moon Velocities & Accelerations, Plus More M13 Music

Today I've listened to the relative accelerations (changes in velocity) between the four Galilean moons of Jupiter as they orbit the planet.  As you can see from the plot below, the values for the accelerations don't go much above 3 km/min/min either accelerating or decelerating.  That translates to 0.83 m/s/s, which is about ten times "slower" than Earth's gravitational acceleration -- or 0.1g.  Pretty cool.

I also show the usual plots of relative velocities....

Line color code:

• Cyan - Io / Europa
• Pink - Io / Ganymede
• Yellow - Io / Callisto
• Green - Europa / Ganymede
• Red - Europa / Callisto
• Blue - Ganymede / Callisto

... and orbits:

Finally, here is the velocity and acceleration audio:

Jupiter Today | 21 December 2015 | Velocity and Acceleration Audio



Continuing study of SDSS image of M13

I took this image of M13 from the SDSS:

and found the 115 brightest stars:

I then calculated the distance, in pixels, between the position of the star and what I determined to be the center of the cluster.  Thus, my calculation is the radial distance of the star from the center of the cluster.  I then converted this distance to an audio frequency and the brightness to an amplitude, and added them all up to get this:
 
The Sound of M13's 115 Brightest Stars I

I then took the ten closest stars to the center and made a tone with them, and then the next ten, and then the next, and the next until I had eleven different tones each containing the audio distances of ten stars.  In what you're about to hear, I run each 10-tone sound for 14 seconds, with one second of overlap.  No idea what this means, if anything.  But I sure do like the sounds produced.

The Sound of M13's 115 Brightest Stars II