With a new year comes many exciting new developments for Universe Sandbox! We’re already hard at work on some of our planned features for 2022, but we wanted to celebrate and reflect on all that we accomplished in the past year.

[h5]New team members[/h5]

Brent was introduced in our 2021 Roadmap and was hired as our new Science Writer & Community Advocate in March 2021. Brent has a Ph.D. in Physics and has been writing about all of the awesome science and simulations that Universe Sandbox can do (including writing this post – Hi again, everybody).

In October 2021, Pavel was brought on as a Physics Engineer to work on all things collisions with Erika, Chris, and Anders. Pavel has a Ph.D. in Astrophysics and did his graduate research on impact simulations, using smoothed-particle hydrodynamics and N-body simulations, mostly focusing on the formation of asteroid families. He’s been hard at work improving our collisions system, and we’re excited to have him on the team.

[h5]Significant updates to Universe Sandbox[/h5]

These encompass over 56 new additions and over 219 bug fixes and improvements! We also started adding screenshots and gifs to show off the new features in each update this year.

• Splish, Splash, Filling a Bath | Update 26.3 | February 24, 2021
  
• Fast & Flurrious | Update 27 | May 3, 2021
  
• Clouds in Motion | Update 27.1 | June 21, 2021
  
• Atmospheric Adjustments | Update 27.2 | August 2, 2021
  
• Codename: Fire Ring | Update 28 | September 23, 2021
  
• My Eyes, the Space Goggles Do Nothing | Update 28.1 | October 28, 2021
  
• Starlite Starbrite | Update 28.2 | November 23, 2021
  
• Planetscaping | Update 29 | December 22, 2021

[h5]New guides and fly-by simulations added to Universe Sandbox in 2021[/h5]

We hope you’ve enjoyed learning about all the new features we added in the last year. We’re planning to add even more guides and spacecraft simulations this coming year.


[h5]Tweets over the course of 2021[/h5]

All of our tweets combined had a total of 361,300 views. Follow us on Twitter to get the latest news about Universe Sandbox.

[h5]Highest number of concurrent users in Universe Sandbox in 2021[/h5]

This is the all-time high for the number of concurrent users and occurred on December 24, 2021! The second-highest number is 646 from the end of December 2020.

[h5]Code commits, or changes, made to the Universe Sandbox project in 2021[/h5]

The most in one week were 102 commits made the week of April 25. This is about the same number of commits as we made in 2019.


[h5]Positive Steam reviews in 2021[/h5]

Being Overwhelming Positive, recent and all time, has really overwhelmed us in the best way. Thank you all for your support and kindness over the last few years. We couldn’t do this without you.


[h5]Discord users in our server at the end of 2021[/h5]

We’re already up to over 6600 since the start of 2022! Join us on Discord.

[h5]Shared items in the Universe Sandbox Steam Workshop[/h5]

While slightly less than in 2019, this is truly an impressive number of creations from the community. Keep up the good work, we can’t wait to see what you all make next!

[h5]Times the Planetscaping tool was used since it was released at the end of December 2021[/h5]

We’re so glad you’ve all been enjoying shaping planets to your whims.


[h5]In-game feedback reports we received this year[/h5]

We appreciate you sharing your feedback with us as we work to make Universe Sandbox the best that it can be.


[h5]Messages sent on Slack (the instant messaging platform we use to communicate)[/h5]

While Slack has become more popular for remote work over the last 2 years, Giant Army has been remote since its founding in 2011. We have 13 team members across 3 continents and 5 time zones, so messaging on Slack is how we get most of our work done.

[h5]Times the Galactic Empire Superlaser was used in 2021[/h5]

We’re sure that none of you had malicious intent when using this laser. It was for science right? Right?


[h5]Random Rocky Planets were created in Universe Sandbox in 2021[/h5]

We’re glad that you’ve enjoyed using these planets as a base for making your own habitable planets or causing epic celestial destruction.


[h5]Times our 13 blog posts from 2021 were read on Steam[/h5]

The most-read post was our patch notes from Planetscaping | Update 29 with 45,933 reads.


[h5]Times Universe Sandbox was opened in 2021[/h5]

That’s roughly once every 6.5 seconds!


[h5]New simulations were created in Universe Sandbox this past year[/h5]

You all create so many amazing things it’s no wonder that there’s a new simulation created every 4.5 seconds.


[h5]Views on the top 4 most viewed YouTube videos about Universe Sandbox this year[/h5]

We’re humbled that GrayStillPlays is still making these videos after all this time.


[h5]Seconds played in Universe Sandbox among all of you in 2021[/h5]

That’s 285 collective years! We know you have a choice when it comes to where to spend your free time and we’d like to thank you for spending it in Universe Sandbox.

There’s so much we want to do in 2022, from finishing up some features we’ve been working on for a while, like rigid body physics and improving our Planetscaping tools, to new features like constellations and multiple materials. And that’s just beginning to scratch the surface.

We’re also planning a big push on mobile development and hoping to start console development this year. Keep an eye out for our 2022 Roadmap which we hope to share soon.

Thank you. We wouldn’t be able to do this without all of your support and help. You all do amazing things with Universe Sandbox that we never could have imagined and that makes us so excited for its future. So whether you’ve been playing Universe Sandbox for 6 minutes or 6 years, thank you. We can’t wait to see how much Universe Sandbox is in another 6 years because of all of you.

The Universe Sandbox Team
Dan, Chris, Georg, Jonathan, Rappo, Mat, Jacob, Erika, Brendan, Anders, Brent, and Pavel

Run Steam to download Update 29.1, or buy Universe Sandbox via the Steam Store.

Planetscaping now has an eyedropper tool to sample the surface of an object to make creating (or flooding) land even smoother. We’ve also improved fragmentation during collisions, among other things.

[h4]Fragmentation[/h4]
We’ve updated how we determine the number of fragments during collisions. This allows fragments to last longer in simulations with numerous collisions and makes collisions more consistent across different simulation speeds.

[h4]Planetscaping Eyedropper[/h4]
There’s now an eyedropper in the Planetscaping tool so you can easily sample and set the Depth, Temperature, and Pressure to match those of the object you are Planetscaping.


[h4]More Highlights[/h4]

• Surface Lock is now a manual toggle, but turns on automatically when you are using the Planetscaping or Laser Tools
  
  
  Before
  

  
  After
  
  
  
• The Solar System - Live View - Planets, Moons, Spacecraft simulation now has 7 additional spacecraft: Parker Space Probe, BepiColumbo, James Webb Space Telescope, Juno, New Horizons, Voyagers 1 & 2
  
  
  
• Here’s a close-up of the James Webb Space Telescope in Universe Sandbox
  
  
  
• We've polished the look and feel of the Planetscaping and Laser tool cursor
  
  
  Before
  

  
  After
  

This update includes 3+ additions and 12+ fixes and improvements.

Check out the full list of What's New in Update 29.1

Please report any issues on our Steam forum, on Discord, or in-game via Home > Send Feedback.

Run Steam to download Update 29, or buy Universe Sandbox via the Steam Store.

Planetscaping is a powerful new tool to design and shape planets to your whims. Surface Lock, which gives a clear, stationary, and illuminated view of the surface of a rotating object, has been enabled to better observe how an object’s surface is changing.

[h4]Planetscaping (Surface Editing)[/h4]
Create continents, freeze oceans, flood planets, and more with Planetscaping. Watch the realistic consequences of your actions unfold as you alter the face of planets. Learn more in our Planetscaping guide:
Guides > Tutorials > Planetscaping



[h4]Surface Lock[/h4]
We’ve made it easier to view how the surface of an object is changing by improving and enabling Surface Lock. This gives a clear, stationary, and illuminated view of the surface of a rotating object when you zoom close to it.



[h4]More Highlights[/h4]

• We’ve added a Blank Planet, like a blank canvas for Planetscaping, to the Add panel
  
  
  
• Collisions have been further improved with updated frictional forces
  
  
  Before
  

  
  After
  
  
  
• We’ve exposed the Elevation Span, the distance between the lowest and the highest elevation point of an object, to better assist with Planetscaping
  

This update includes 5+ additions and 18+ fixes and improvements.

Check out the full list of What's New in Update 29

Please report any issues on our Steam forum, on Discord, or in-game via Home > Send Feedback.

Run Steam to download Update 28.2, or buy Universe Sandbox via the Steam Store.

Stars have new Absolute and Apparent Magnitude properties, which measure their brightness from different distances. This minor update also includes improvements to black hole collisions, object trails, and bug fixes.

[h4]Stellar Magnitudes[/h4]
Stars now have both Apparent and Absolute Magnitude properties, which are measures of the brightness of a star, under Properties > Temperature. Learn more in our new Stellar Magnitudes guide: Guides > Science > Stellar Magnitudes.



[h4]More Highlights[/h4]

• Colliding black holes now compute the correct Schwarzschild radius
  
  
  Before
  

  
  After
  
  
  
• Trails for objects are no longer broken and jagged when an object is set as the trail center
  
  
  Before (Bug)
  

  
  After (✔️ Bug Mitigated)
  
  
  
• Starlight color on nearby objects now updates in real-time
  
  
  Before
  

  
  After
  
  
  
• Human scale objects are now simply heated by stars and supernovae to better reflect their temperature in space
  
  
  Before
  

  
  After
  
  
  
• Created a new guide about object oblateness and its effect on gravitational fields under: Guides > Science > Non-Spherical Gravitational Fields
  

This update includes 3+ additions and 13+ fixes and improvements.

Check out the full list of What's New in Update 28.2

Please report any issues on our Steam forum, on Discord, or in-game via Home > Send Feedback.

Run Steam to download Update 28.1, or buy Universe Sandbox via the Steam Store.

We’ve improved the “Realistic” Object Visibility setting to better reflect the sensitivity of the human eye to object brightness and colors. We also added a new “Enhanced” Object Visibility, improved collision detection, smoothed out habitable zones, added bug fixes, and more!

[h4]Realistic Object Visibility[/h4]
The “Realistic” Object Visibility setting now shows objects fading in and out with adjusted colors tuned to what the human eye would see. Learn more in our guide, Limits of Human Eyes.


[h4]Smoother Habitable Zones[/h4]
The habitable zone now smoothly changes size for stars of all luminosities, including very hot, bright stars like Rigel. Check it out under View > Habitable.


[h4]More Highlights[/h4]

• “Enhanced” has been added as an Object Visibility option, which removes rim lighting from objects while keeping them always visible
  
  
  
• Collision detection has been further improved as part of our continued work to make collisions even better
  
  
  Before (Bug)
  

  
  After (✔️Bug Mitigated)
  
  
  
• We’ve added a satellite to our human-scale objects
  
  
  
• Created simulation of ESA and JAXA’s BepiColombo spacecraft flyby of Mercury in October 2021: Open > Historical > BepiColombo Flyby of Mercury in 2021
  
  
  
• Open, Guides, and Workshop panels can now be pinned open, allowing for much easier simulation browsing
  
  
  
• The View Settings panel has been reorganized for better clarity and usability
  
  
  Before
  

  
  After
  

This update includes 6+ additions and 12+ fixes and improvements.

Check out the full list of What's New in Update 28.1

Please report any issues on our Steam forum, on Discord, or in-game via Home > Send Feedback.

Run Steam to download Update 28, or buy Universe Sandbox via the Steam Store.

Fire Ring introduces a collision model that simulates an impact shockwave across the surface of an object, as part of our work to continuously improve collisions. In addition, there are improvements to object trails, additional object information, bug fixes, and more.

[h4]Shocking Collisions[/h4]
Object heating from impacts now realistically moves over the impacted object as a shockwave. Fragments are ejected from the edge of the shockwave at more realistic angles. Learn more in our Collisions guides:
Guides > Tutorials > Planetary Collisions
Guides > Science > Collisions: Energy, Mass, and Speed


[h4]Impactor Heating[/h4]
Both objects involved in a collision now experience collisional heating on their surfaces, instead of just the larger object.


[h4]More Highlights[/h4]

• Grazing collisions now look more realistic with shockwaves and surface dragging

• Object trails are now projected back in time to show their full past trajectory

• Objects now have additional information (like, planet, moon, rogue object) in the property panel based on their relative motion around other objects

• As we work toward making our simulations more deterministic, seeds for randomized simulations are now easier to find, allowing you to recall previous random scenarios

This update includes 6+ additions and 22+ fixes and improvements.

Check out the full list of What's New in Update 28

Please report any issues on our Steam forum, on Discord, or in-game via Home > Send Feedback.

Universe Sandbox on iOS! We’re also working on an Android version.

You can purchase Universe Sandbox via the Steam Store.

Have you ever wanted a universe in your pocket? We have too, and so we’ve been actively working on a mobile version of Universe Sandbox for both iOS and Android to make this a reality.

Universe Sandbox for mobile will have the same features and interface as the desktop version (in fact mobile and desktop are built from the same source code) and we are working to make sure it is an equally enjoyable experience.

Our work on mobile has motivated many features and improvements that have already been made to the desktop version. This includes automatic scaling of graphics settings based on screen resolution and the separate, minimizable panel that comes up when you use a tool, like the laser. Additionally, optimizing Universe Sandbox for mobile has the added benefit of improving performance on the desktop version.


Adapting Universe Sandbox for mobile challenged us to simplify our user interface to its core, resulting in changes like the separate, minimizable panel for the tool currently in use, like the laser (shown in the lower right here on a smartphone).

For the last few months, we’ve been focusing on making sure the mobile version is just as fun to play as the desktop version. In Update 26, we unified the user interface across desktop and VR, and we’re continuing to develop this unified interface with physically smaller (that is, mobile) screens in mind. You can check out how we are building this flexible user interface right now by making the window in the desktop version small. If you do try this, you’ll notice it presents quite a design challenge, not only for existing features but also for any features we add.


The interface filling up the entire screen on a mobile phone shows how challenging it can be to fit all of the windows on a smaller display.

You may have seen some of the improvements we’ve made to our user interface in recent updates. For example, our bottom bar redesigns both create a sleeker, more adaptable desktop experience while also making everything more accessible on mobile. However, we are still working on solving a few design challenges including (but not limited to):

• What’s the best way to manage all of the different panels on a small screen (our guide system creates particular challenges)?
  
• Working around the limitations of minimum button sizes required for a touchscreens
  
• How do we make the user interface work in both portrait and landscape orientations?

Lower amounts of memory on mobile phones, as well as hardware limitations leading to poor performance, are two of the challenges we are still working on to get Universe Sandbox to run smoothly on mobile devices.

We have been working on numerous updated user interface designs that improve functionality and clarity no matter what device you are on, and implementing those is one of our major next steps. We’re also currently hiring a cross-platform engineer to help bring Universe Sandbox to mobile and beyond.


There are occasional bugs to fix in the mobile version, such as this one showing patchy trails on an iOS phone at high simulation speeds. (By the way, we fixed this bug!)

While we still do not have a release date or official price for mobile, we currently plan on it being a one-time paid app with no ads or in-app purchases. We hope to write more of these mobile-focused DevLogs as we make more progress, so stay tuned!

If you want to receive updates when there is new information about mobile, like this DevLog, sign up for our mailing list:
http://universesandbox.com/mobile/

To join our community discussions, please join us on our Steam Forum and our official Discord community.

Run Steam to download Update 27.2, or buy Universe Sandbox via the Steam Store.

You can now change specific simulation interactions, like gravity and collisions, on a per-object basis! This minor update also includes simulated atmosphere opacity (a measure of how hard it is to see through the atmosphere), bug fixes, and more.

[h4]Individual Object Simulation Manipulation[/h4]
The ability to turn off specific simulation interactions on a per-object basis has been added to all objects in Properties > Overview. We plan to add to this over time, and we hope you enjoy creating all kinds of crazy scenarios with these options as much as we do!



[h4]Opaque Atmospheres[/h4]
Atmosphere Opacity is now simulated based on an object's properties, like Radius and Atmosphere Mass. Learn more about this new feature in our Atmospheres guide under Guides > Science > Atmospheres.



[h4]More Highlights[/h4]

• Polar ice caps on random rocky planets are now informed by the water depth around the poles and are no longer circles
  
  
  
  Before
  

  
  After
  
  
  
• Opening multiple surface data views no longer causes a noticeable reduction in performance
  

This update includes 7+ additions and 13+ fixes and improvements.

Check out the full list of What's New in Update 27.2

Please report any issues on our Steam forum, on Discord, or in-game via Home > Send Feedback.

Universe Sandbox now realistically simulates the speeds at which clouds rotate.

One of our recent improvements to Universe Sandbox includes realistically simulating the speed at which clouds rotate around objects, like planets and moons. While our in-game guide, which can be found under Guides > Science > Clouds, shows off these new features, we wanted to explain them in a little more depth.

To simulate completely realistic clouds, we would need to do a full weather simulation, including the water cycle. As we talk about in our Snow Simulation ScienceLog, this isn’t currently possible without a supercomputer, so for now our clouds are drawn from pre-made cloud pictures. However, we determine the speed at which clouds rotate around an object’s surface from two simulated effects.


Simulating realistic weather patterns faster than real time (one second per second) is very difficult, especially with your average computer.

In reality wind is initially created going in an unexpected direction - it travels outwards from the equator to the poles instead of rotating around the equator.

This is because objects are (generally) warmer at their equator and colder at their poles. The higher temperatures at the equator lead to a higher air pressure (essentially the weight of the atmosphere) at the equator, while colder temperatures at the poles lead to lower air pressure. The high pressure air at the equator moves to the lower pressure air at the poles, creating a wind that moves the clouds with it.

This wind moves faster, increasing the cloud speed, the larger the temperature difference between the equator and the poles is, since this will create a larger air pressure difference. In Universe Sandbox we simulate this difference in air pressure between an object’s equator and its poles based on the difference between its Minimum and Maximum Temperature, which are usually at the poles and equator.



By lasering Mars, we are increasing the maximum temperature, which increases the difference between the maximum and minimum temperatures on Mars, as well as the difference between maximum and minimum air pressures, which increases the cloud speed.

So if wind, and clouds, starts out moving from the equator to the poles, why is it that in reality (and in Universe Sandbox) the wind and clouds move around the Earth’s equator?

This has to do with something called the Coriolis effect - the second effect we simulate for our cloud rotation speeds - which is an effect that occurs on any object that rotates. The Coriolis effect creates a force, called the Coriolis force, that pushes the wind around the Earth’s (or any object’s) equator. The strength of this force increases the faster the object is rotating.

So we now have two effects pushing the winds, and thus clouds, in two different directions:

So how do we arrive at the final wind, and cloud, rotation speed? The wind speed will increase until the strength of both effects on the wind is the same. When this happens, the wind and clouds end up rotating around the equator of the object at a constant, unchanging speed. In Universe Sandbox this speed is taken as the Cloud Rotation Speed.

A really interesting effect that happens when our two simulated effects have the same strength is that the faster an object rotates, the slower the cloud speed will be.


The cloud rotation speed here is changing only based on the rotation speed of Earth. Slower planet rotation speeds lead to faster cloud rotation speeds, which is not what you’d expect at first.

A faster object Rotation Speed creates a stronger force from the Coriolis effect, which allows the two effects to reach an equal strength more quickly. This means that the wind speed has less time to increase before it becomes constant. The result is that the final wind, and Cloud Rotation Speed, is slower.

In addition to Rotation Speed and the Minimum and Maximum Temperature, the strength of the wind that is created from the temperature difference also depends on the Atmosphere Mass, the Surface Gravity, and the Radius of the object (see the Bonus Math section below for details). This is because a more massive atmosphere will slow down the Cloud Rotation Speed, since it is harder to move, and a smaller object radius will increase the Cloud Rotation Speed, since it is easier to move air around a smaller object.

While simulating these effects is a welcomed advancement in our cloud simulation, there are still many improvements we would like to make. This includes dynamically generating clouds and giving them more realistic material compositions. For now, try experimenting with different object properties to see how they affect the Cloud Rotation Speed. We recommend the object’s Rotation Speed, since we can’t slow down the Earth in real life (nor would we want to), this is a great way to see some amazing science at work!



This blog post is part of our ongoing series of ScienceLog articles, intended to share the science behind some of Universe Sandbox’s most interesting features. If you would love to learn about the real-life science powering our simulator, please stay tuned and let us know what you would like to read about next.

To join our community discussions, please join us on our Steam Forum and our official Discord community.



If you’re interested in exactly how different object properties relate to both the force from the difference in the air pressure between the equator and the poles (called the pressure gradient) and the force from the Coriolis effect (called the Coriolis force) then you’ll enjoy this extra little bit of math.

When we simulate the cloud rotation speed we figure out the pressure difference, ΔP, which is based on the maximum atmosphere surface pressure, Pmax. This is the surface pressure at the equator, and depends on the Atmosphere Mass, M, the Surface Gravity, g, and the radius of the planet, R,



The pressure and temperature of a gas are related (by something called the Ideal Gas Law), so we can compute ΔP using just Pmax and the maximum and minimum temperature, Tmax and Tmin , of the object,



Now that we have this pressure difference, we can compute the force, F, that this pressure gradient applies over a certain amount of air mass, m. This force per mass is what causes winds and clouds to move and depends on ΔP (and a few other less important things). That means that this force can change depending on M, g, R, Tmax and Tmin , (that is Atmosphere Mass, Surface Gravity, Radius, Maximum Temperature, and Minimum Temperature respectively) so all of these properties affect the cloud rotation speed,



Here the ∝ symbol means “proportional to,” which is similar to an equals sign, “=”, but leaves out some of the less important values. The Coriolis Force also provides a force per mass in order to move clouds. This force is dependent on a few different things, but in particular it depends on the rotation speed of the planet, Ω, and the speed that the wind is already moving due to the pressure gradient, v,



To reach a balanced state where the wind, and clouds, are moving around the equator of an object at a constant speed, the two forces must be equal, leading to the relationship



Now the value we want is the wind, or cloud, rotation speed, v. Rearranging the above equation gives us



So what does this mean? First, the larger the difference between the minimum and maximum temperature, the faster the clouds will move. This is because a larger temperature difference means a larger pressure difference, thus faster winds.

It also shows mathematically why a more massive atmosphere slows the cloud rotation speed and a smaller radius can dramatically increase the cloud rotation speed like we discussed above.

But the most interesting consequence of this relationship is that it shows why it is that the faster an object rotates, the slower the cloud speed will be. This result was so surprising to us at first that we had to triple check it (we’re convinced it is correct now, don’t worry). While it’s impossible to slow down the Earth’s rotation in reality (not to mention the immense destruction that would cause if we could), exploring in Universe Sandbox allows you to see the consequences of some beautiful math for yourself.

Run Steam to download Update 27.1, or buy Universe Sandbox via the Steam Store.

Cloud speed is now simulated based on an object's temperature and rotation speed. Surface simulation performance improvements, an Appearance interface redesign, adjustable planetary rim lighting, and more round out this minor update.

The feature image shows a laser heating up the Earth to speed up the cloud rotation with no planetary rim lighting.

Cloud speed is now simulated based on an object's temperature and rotation speed as part of our continued incremental improvements of clouds. Check out our new Clouds guide for a tour through our entire cloud system: Guides > Science > Clouds.


As part of our continued user interface improvements, the Properties > Appearance tab has been redesigned to combine color customization with visibility and other options to make changing the appearance of an object even easier.

• Surface Simulation has been improved to update only objects that are changing each frame, improving performance for simulations with many objects
  
  
• Created simulation of NASA’s Juno spacecraft flyby of Ganymede in June 2021: Open > Historical > Juno Flyby of Ganymede in 2021
  
  
  
• Star glows correctly fade as you get farther away from them when Object Visibility is set to Realistic again
  
  
  
  Before
  

  
  After
  
  
  
• Added Atmosphere Density and Speed of Sound Properties to Properties > Surface > Atmosphere
  
  
  
• Rim Lighting can now be adjusted under View > Object Visibility > Rim Lighting
  

This update includes 8+ additions and 21+ fixes and improvements.

You can also check out our 2021 Roadmap to learn more about what we’re currently working on!

Please report any issues on our forum, on Discord, or in-game via Home > Send Feedback.

Check out our full list of Update 27.1 changes