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International Space Station

Low Earth orbit

Virtual International Space Station
Virtual International Space Station
by NASA Langley Research Center Spacecraft & Sensors Branch,
circa January 2001

The Virtual International Space Station (VISS) was developed to support commercial (private) development of the ISS, by providing a way for researchers and scientists to explore the space station and understand the laboratory equipment available in it.

In the VISS, you can walk about the interior and fly around the exterior as if you were on a space walk. Selected components of the station have markers, or question marks ("?"), you can click for additional information (accurate circa 2001/2002).

This two-minute NASA Connect video explains more.

Unfortunately, visiting the Virtual International Space Station requires a browser feature called WebGL, which your browser doesn't support. Try downloading and installing current versions of Mozilla Firefox, Google Chrome, or using Microsoft Edge on Windows.

Unfortunately, visiting the Virtual International Space Station requires a browser feature called WebGL, which your browser supports, but can't use on your device. This may be because you're on a mobile device, or your computer's video card is too old, or your video card's drivers are out of date. Try visiting get.webgl.org to learn more.

Visit the Virtual International Space Station in your browser! (~60MB download, requires a mouse and keyboard, not recommended for mobile devices, double-click your primary mouse button to switch between 3D movement and 2D clicking on markers)

Questions or problems? See the FAQ.

Technical notes

In the console area below the Unrealty window, you might occasionally see the error, "ScriptLog: Unrealty Error! Player died, and they aren't supposed to!" This would normally not be visible to a user, and indicates either a problem with the map, or an uncaught side-effect from Unrealty's origins in video games.

There's no "up" or "down" in space, but there is in the VISS. Users are unable to flip "upside down" in the VISS due to limitations of the stock Unreal engine. (Modifications to Unreal Engine 2 and later did support six degrees of freedom.)

Double-clicking switches between 3D movement and the 2D "agent" interface, supporting clicks on the question mark "markers" to bring up information windows about the ISS. The VISS may have been the first third-party locale to use the add-on "agent" technology, which did not ship with the original Unrealty client.

Space Commercialization CD-ROM

International Space Station Space Commercialization CD-ROM
International Space Station Space Commercialization CD-ROM
by NASA Research Integration & Product Development Division,
Office of Biological and Physical Research
circa January 2001

The Virtual International Space Station was released as part of a "International Space Station Space Commercialization" CD-ROM in January 2001.

(The first resident crew aboard the ISS, Expedition 1, had only arrived two months earlier, in November 2000.)

The CD includes video, a full copy of the commercial.nasa.gov web site, and documentation about the space station's capabilities circa January 2001, "to assist industry in understanding ISS commercial opportunities, capabilities, and activities."

(Like the original Unrealty software, the included video can no longer be played back with standard desktop or mobile software. Third-party playback software like VLC must be used.)

The Internet Archive has a copy of the Space Commercialization CD-ROM.

The Internet Archive's Wayback Machine has an archive of commercial.nasa.gov from January 24, 2001.

Later virtual models

The Virtual International Space Station made have been the first generally-available, consumer-friendly, virtual model of the ISS, but it wasn't the last. The ISS would go on to be modeled in every version of the Unreal engine.

In 2009, the Canadian Space Agency would release RoboMath, built with Unreal Engine 2. RoboMath (and later, RoboMath3) was educational software set in the ISS, where students could solve mathematics problems based on the STS-127 mission, with an avatar of Canadian astronaut Julie Payette guiding them.

In 2013, designer Bartek Nowak modeled the ISS in the Unreal Development Kit, based on Unreal Engine 3.

In 2015, a VR video game called Earthlight was announced, offering a space experience built in Unreal Engine 4.

In 2017, NASA discussed their "mixed reality" astronaut training model of the ISS, also built in Unreal Engine 4.

While not made with Unreal Engine, perhaps closest to the original VISS experience is the new VR video game, Mission: ISS, which includes full virtual reality touch controller support, six degrees of freedom, and interactive markers within the space station, providing technical details about its systems and components.

Original credits

The VISS was developed by the NASA Langley Research Center Spacecraft & Sensors Branch. Modeling of the ISS was performed by Analytical Mechanics Associates, Inc. of Hampton, Virginia.

The ISS model data is derived from the International Space Station On-Orbit Assembly, Modeling, and Mass Properties Data Book, JSC-26557 (LESC-31166). System information was taken from the ISS Familiarization document (ISS FAM C 21109). Research capabilities are from the International Space Station User's Guide, Release 2.0.

Original downloads

If you have a functioning version of the original Unrealty software on a Windows 95/98/XP or Mac OS 9 machine, you can download the original VISS locales. v1 was shipped on the CD-ROM in January 2001; v2 was released October 2002, and is the version offered online.

You will not be able to install both simultaneously; v2 will overwrite v1. Unfortunately, a list of differences is not available. Technical support is not available. Multiuser server discovery is not available.