The latest update for Universe Sandbox, version 36.1, brings the Artemis II mission directly into the hands of players. Released on April 29, 2026, this update focuses on recreating humanity's farthest journey from Earth with a high degree of scientific accuracy.
Artemis II Simulation
A new simulation titled "Artemis II: Humanity's Farthest Journey" is now available. It models the free-return trajectory of the recent Artemis II mission, which swept around the far side of the Moon. Players can experience the path taken by the crew, including the iconic Earthset view captured by the astronauts. The simulation is designed to provide an educational perspective on the mission's orbital mechanics.
Orion Integrity Spacecraft
The Orion Integrity spacecraft, the capsule used during the Artemis II mission, has been added to the game's object library. Users can place it into any existing simulation or view it within the dedicated Artemis II scenario. This addition allows for detailed exploration of the spacecraft's design and its role in the mission.
Object Cohesion and Fragmentation
Update 36.1 introduces a significant simulation improvement regarding object cohesion. The game now calculates how tightly bound an object is based on its composition. This directly affects deformation and fragmentation rates during collisions or when objects spin rapidly. For example, fast-spinning asteroids like 2014 RC will no longer immediately tear themselves apart, as the simulation now accounts for their internal material strength. This change adds a layer of realism to celestial body interactions.
Simulation Fixes and Improvements
Several fixes address simulation stability and accuracy. Gas and dust clouds created from Roche and spin fragmentation no longer rotate, improving visual consistency. The particle spin rate distribution during creation has been adjusted to increase average rotation speed. Collision fragment randomization has been improved to prevent fragments from being ejected in clusters.
Key fixes include:
- Limiting atmosphere layers to a maximum of 1000 for extreme objects.
- Preventing objects with fast rotation or large deformations from fragmenting when values are decreased while paused.
- Resolving performance issues where collisions between objects of significantly different densities caused the game to freeze.
- Ensuring the camera continues along the deleted object's path instead of becoming stationary.
User Experience Enhancements
The update also refines the user interface. Atmosphere Scale Height and Surface Heat Capacity now display indicators for simulated versus custom values. Double-clicking for object selection has been improved, especially at high simulation speeds. Scientific notation formatting in labels has been updated for readability. Screenshot Settings now use a dropdown menu with presets, allowing for more customization in the future.
Panel behavior has been improved: panels remember their size between sessions within a simulation, and they retain scroll position when expanded. When loading new simulations, interface panels now load simultaneously, preventing layout shifts. A screenshot of the current simulation is taken and displayed as the main view during loading.
Bug Fixes
Several bugs have been addressed. The Mystery Button, which appears on April 1, now functions correctly when enabled in Debug settings. Atmosphere Scale Height saves and loads properly when manually adjusted. The Settings menu no longer disappears after using in-game GIF capture tools. Object property locks now only change state when the property value is actually adjusted. Issues with collision and attraction settings being unchangeable have been fixed. The camera no longer lands below an object's surface in cases of extreme deformation. Trail Center changes for individual objects now apply correctly.
Update 36.1 is available now for all Universe Sandbox players. The update can be accessed through Steam, Discord, or the in-game feedback system.
