What is Universe Sandbox 2?
Universe Sandbox 2 is a physics based space simulator.
Create, destroy, and interact on a scale you've never before imagined.
Shoot asteroids at the Earth or cause a run away greenhouse effect. Rip apart the rings of Saturn or blow up the Sun.

Ultimate Power
- Spawn massive stars, launch asteroids, and manipulate gravity with just a few clicks.
Fun & Interactive
- Explore our universe through unlimited experimentation.
Easy to Use
- Intuitive, game inspired controls make creation and destruction effortless.
Real Physics
- Use Newton's law of gravity to simulate the motions of the planets, moons, and stars.

- Changelog -
Alpha 12 (30.10.2014):
New Features
Thumbnail tile grids
- In the Add panel, select icons at the top to filter the list of objects
- In the Create panel, select icons to choose different tools
- Click a tile to load a preset
- Hover to see a description of the preset
- Use custom settings: hover over the preset, click the edit icon, then press the Create button at the bottom of the window
Create → Systems
- Generate a random solar system by selecting a preset
- Edit the settings to customize parameters such as the center body, number of planets, and planet distance
Create → Encounters
- Load a preset to create a simulation of a rogue planet approaching and passing through our solar system
- Edit the settings to customize parameters such as start date, time step, and the rogue’s target
Create → Grid
- Load a preset Material Grid or Fragment Grid simulation for technical demonstrations
Powers → Exploder
- Select the power and then click a body in the simulation to explode it (first pass on the feature, much work to be done)
Simulations
- Jupiter In Between Suns
- Earth In Between Suns
- 4 supernova sims
- Supernova Closeup in Real Time, Supernova in Galaxy, Supernova in the Solar System, Stellar Evolution of our Sun
Pumpkins!
- Add → Human Sized Objects
Improvements
Choreography
- A total of 201 2D and 25 3D choreographies
- Added a Mass Randomizer setting
- Default lighting set as “flashlight” mode with shadows disabled
Collision fragments
- Now ejected from both bodies if they have a composition
- Compositions consistent with body’s composition
- Total fragment amount calculated by the most prevalent materials in the body, e.g. a rocky body will eject mostly silicate fragments
- They now smoothly transition to bodies with composition-calculated sizes
- Improved particle budgeting for better performance
Supernovas
- Lightcurve calculations for accurate expansion and temperature effects
- Supernova clouds now fade towards the end of their lifetime
Planetoid rendering
- Unified shading based on temperature, state, and composition
- Now always spherical when in liquid state
- Improved transitions for shape, color, opacity and normals of freezing and thawing planetoids
Simulation
- Added "Semi Major Axis" as a Chart mode preset
- Random gas giants have a greater variety in color
- Stars default to having age locked, rather than mass
- All atmosphere variables now update when Climate is enabled
UI
- Added Info & Stats section to Simulation panel (body count, total simulation mass,etc.)
- Added YEAR-MONTH-DAY date to Solar System-based simulations and Encounters
- Preview panel can be resized vertically by dragging its bottom edge
- It will also maintain aspect ratio when property window is resized horizontally
- Moved expanding submenus below Powers
- Swapped Open and Create in Home panel
- Added options for 2x, 4x, 6x, 8x, 10x sized screenshots in menu
- Improved naming of saved screenshots
- Moved window resolution presets to bottom of Settings panel (instead of in Main)
- Removed "chart" quick button when hovering properties
- Resizing the window on startup will now keep it that size
- Logo is no longer blurry with low graphics settings
Fixes
- Particles won’t disappear if no other bodies are present
- Planetoids now display correctly in preview window
- Objects now have same scale in preview
- Trails display properly for very low velocity objects
- Body trails don’t flicker for one frame
- Capped max simultaneous sounds to 32 to respect audio subsystem limits
- Solar system objects will not spawn away from the cursor
- Mean Anomaly now reflects values greater than 180
Alpha 11.3:
- Just a small fix to a bug we introduced in Alpha 11.2 when initializing Earth’s climate that made our planet too cold. This also fixes an issue with the game window forcing itself on top of other windows.
- The next major update will feature major improvements to collisions and fragments to make them even more spectacular.
Alpha 11.2:
- Improved the Auto Orbit command and fixed a couple small bugs.
Alpha 11.1:
Improvements
- Overhauled stellar database with more accurate values
- Added % to ppm UnitType
- Steam startup option: -window or -windowed
- Forces windowed mode on startup (overrides user setting)
- Added consistent 'Preset' and 'Settings' labels for all Create, Rings, and Tethers panels
- Added a horizontal line to separate Presets and Settings in create panels
Fixes
- Disabled dynamic showing/hiding of Orbital Parent in Property window
- Fixes flickering text bug
- Enforced startup resolution in windowed mode (will then switch to user setting)
- Fixes issue of users stuck in fullscreen mode and unable to start
Alpha 11:
New Features
- Shockwaves from collisions that travel along a body’s surface
- Choreography
- Home → Create → Choreography tab
- Change parameters or use the presets to load interesting multiple-body orbital patterns
- New Simulations
- “2014 RC” - asteroid which recently passed by Earth
- “Moons, 75 orbiting Earth”
- New tutorial text for sims under “Astronomy”
Improvements
- Changed Steamworks integration - should fix issues for Linux users
- Added back a number of integrators, so there are 8 in all now
- Supernova graphical improvements
- Improved handling of extreme Carbon Dioxide levels
- Added "Optimize for Climate View" under "Display Settings" in the Climate tab of Properties window
- First pass at supernova effects
- Affected bodies will heat up
- Added new options for collisions under Collide tab
- Position Offset for easy grazing collisions
- Time before collision in real seconds (defaults to 1)
- Time between groups
- Time between additional bodies
- Added grazing collision presets
- Improved startup experience with progress text
- Renamed New tab to Create
- Added new units for Carbon Dioxide: 2010 level on Earth and preindustrial Earth
- Minor atmosphere opacity improvement
- Changing computing device setting now updates both the gravity calculator and the collision detector for better performance
- Better integration between climate and collisions
- Velocity can now be graphed and used as variable in chart mode
- Trails hide when selected body is viewed up close
- Adjusted performance score rating
- Improved debug logging
- Added Steam user info (name, ID, on/offline status, steam level) to bug, comment, and performance test emails
- Added button to Climate tab of Properties window to optimize display settings
- Changed default add mode to Binary (from Binary Balanced)
- Minor tweaks to start up logo and text placement
- Highlighted user interface items now flash in light blue
- Tutorials no longer highlight user interface items when closed
- Improved introduction tutorial
- Changed default solar system time step to 15 days per sec
- Camera’s targeted bodies no longer show preview window by default
Fixes
- Controller input is now disabled by default - fixes spinning camera issue
- Fixed temperature occasionally initializing at 0
- Fixed issues with artifacts on far away bodies
- Fixed an issue that caused ForceCPU to start with wrong compute device
- Fixed issue with impactors remaining after being destroyed
- Attempting to load a deleted simulation no longer causes an error
- Fixed a bug that occured when camera’s target body was removed
- Fixed bug that prevented tutorials from advancing after simulation load
Alpha 10.1:
Improvements
- Graph window now refreshes and retains targets when sim is reloaded or closes when a different sim is loaded
- Adjusted age of Wolf 359 to give the correct radius
- Added 'Auto Orbit' button to Simulation panel actions list
- New cursors when hovering over move/rotate gizmo
- "Find best settings" and "Reset settings" now set good display mode and resolution
- User can now set temperature even when Climate is on; Climate will reinitialize hot or cold
- Added "Random Small Moon" option to Add panel
- Press Ctrl+T to delete trails, Ctrl+D to delete dust, Ctrl+F to delete fragments
- Rearranged options in Settings
Fixes
- Added limit for maximum spin caused by collisions
- Fixed a bug that caused the gizmo to constrain rotation axis while the axis rings were hidden
- Plus/minus buttons now correctly change negative property values
- Made atmosphere-less cooling consistent across planetoid and terrestrial planet types
- Fixed unit for Climate starting temperature
- Entering a new celsius value now works correctly
- Fixed bug that prevented feedback from sending
- Fixed bug with out-of-sync arc ball
- Fixed another bug relating to incorrect heating and cooling times
- Adjusted factors for determining initialized temperatures for new bodies
- Collision particles now initialize with correct temperature
- Temperature will no longer reinitialize when first enabling climate on an Earth
- Fixed bug that allowed bodies to continuously orbit and overlap each other

Last but not least:
If you like the game, support the developer, buy it!  
http://universesandbox.com/2