Universe Sandbox ² - Body Colors

Alpha 13 is our biggest update yet.

Overhauled collisions, Mars climate, planetary cutaways, tidal heating and evolution, working orbital elements controls, a better looking UI, and much, much more.

Run Steam to update or buy Universe Sandbox ² now: universesandbox.com.


It’s our biggest update, and it’s also the update we’ve spent the most time on. A lot of this was due to the amount and complexity of the features we’ve been working on. But there were also quite a few unforeseen obstacles and bugs, and add to that some holiday time off… in short, it took us longer than expected. But now there’s plenty to explore, and we don’t think you’ll be disappointed.

In a previous blog post, we showed previews of planetary cutaways, Mars climate simulation, the collision rewrite, and radial velocity and light curves. These are big parts of Alpha 13, but there’s no need to repeat ourselves; let’s look at something new.

Alpha 13 introduces a vastly improved graphing tool. It now plots simulated time, autoscales and autoscrolls, and allows for customizable X and Y axes. You can view specific data by hovering your cursor, and you can easily add and change targets.

Universe Sandbox ² - Climate and Graph

Combine that with the new climate feature that lets you simulate future greenhouse gas emission scenarios to get a clearer picture of what could be in store for Earth’s future. To learn more, run the Climate Scenarios activity in Home -> Main -> Activities.

In the screenshot above you can also see the new Milky Way background, the new font, and some new icons for the Properties window.

Also added to the UI is a list of icons at the bottom of the screen that show the bodies bound to the 1-8 number keys. Press 4 a few times to launch some moons at the Earth then turn on the new Body Colors mode for a colorful light show. With Body Colors, the colors of trails, bodies, and fragments are adjusted by mass, acceleration, or velocity.

Universe Sandbox ² - Collisions

The new collision system under the hood mean that these collisions will run faster and look better. Calculations have been improved for fragments, craters, momentum, temperature, and every other element of collisions.

The rewrite to physics also introduces a new Global Adaptive integration mode. This mode ensures that, at no matter the timestep, the simulation will retain an accuracy within a user-defined “tolerance” level. This keeps bodies on their proper paths, even when you’re running at thousands of years per second.

Check out our What’s New for a full list of new features, improvements, and fixes. It’s a long list.

We plan to return to a more regular update schedule for Alpha 14. Until then, there’s a lot for you to check out in Alpha 13.

Let us know what you think: