As computers have grown ever more powerful, astronomers and astrophysicists have increasingly used computers to model the complex systems they study. This can range from modelling the motions of planetary bodies in our solar system, to simulating the convection of plasma in the depth of a star. Perhaps the most ambitious computer modeling project, however, is the Millenium Project at the Max Planck Institute.
Battle of the Planets
The 55 Cancri system is in some ways very similar to our own. The star is about the same mass and size as our Sun, and it has a Jupiter-sized planet at a distance of 5.7 AU, which is just slightly more distant than Jupiter’s 5.2 AU distance. It has three other gas planets, as well as a super-earth. One would think that the system might be similar in other ways, such as having rocky planets close to the star and gas planets more distant. But this is not the case.
Close Encounters
Just how stable is the solar system against close encounters with stray planets? Pretty stable, and we can show that with a bit of computational physics.
First World Problems
If you try to compute an N-body problem in Mathematica on a laptop, you’re going to have a bad time.
The Error of My Ways
When you do computational astrophysics, you can get errors in your results. The trick is to recognize where those errors lie, and to learn to minimize them.
Rotating Stars
Some stars rotate very quickly. So quickly that they bulge significantly at their equator. Is there a maximum rate of rotation? We can use a simple model to find out.
Building a Better Star
We revisit the simple model of a star to see how to make a better stellar model.