Tag Archives: gravity

Barnes-Hut for N-body force calculations

Posted on June 26, 2011 by ejrh

Seen on Reddit a couple of days ago, a nicely presented article on the Barnes-Hut algorithm.

Posted in Science, Simulation | Tagged , | 1 Comment

Galaxy animation from 2010

Posted on March 14, 2011 by ejrh

I’ve been rewriting a gravity simulator (see my earlier posts on ephemerides and relativity).  This isn’t because I’ve thought of a better design or come upon a better technology for it.  It’s because I lost the first version!  I’ve recovered … Continue reading →

Posted in Science, Simulation | Tagged | 3 Comments

Faking relativity

Posted on March 5, 2011 by ejrh

As you know, the orbit of Mercury about the Sun cannot be explained entirely by Newtonian physics. In an ideal Newtonian system, the orbit of a small body around a larger one is a stationary ellipse. In the case of … Continue reading →

Posted in Science, Simulation | Tagged , , | 3 Comments

Ephemerides from JPL Horizons

Posted on February 10, 2011 by ejrh

Ephemeris is a strange word that evokes both scientific and mystical ideas.

Posted in Science, Simulation | Tagged , | 6 Comments