If you already own Universe Sandbox ², just run Steam to update to the latest version.
Or you can buy Universe Sandbox ² here:
http://universesandbox.com/buy/What's new?Alpha 15 is the biggest update yet for Universe Sandbox ². We redesigned the user interface for a cleaner, more intuitive experience, rewrote physics for better performance, and introduced a dynamic soundtrack. There are also magnetic fields, light pulses, fireworks, custom keybindings, and a ton of smaller improvements, changes, and bug fixes.
In Alpha 15.1 we updated the look of Ceres based on the latest photos from NASA, added a random asteroid feature, new moons of Pluto, pulsar jets, and improved the look of brown dwarfs. We also re-introduced the ability to customize launch bodies. Hover over bodies in the Add panel then press a number key to assign the body to that launch slot. There are also a handful of other improvements and bug fixes.
Complete List of UpdatesLet us know what you think! And please report any problems either with the in game feedback tool or by starting a new thread...