Jeb, an alien from the video game Kerbal Space Program, is seen in plush form on board Boeing's CST-100 Starliner spacecraft as the "zero-g indicator" for the Orbital Flight Test-2 (OFT-2) mission to the International Space Station.

Jeb, an alien from the video game Kerbal Space Program, is seen in plush form on board Boeing's CST-100 Starliner spacecraft as the "zero-g indicator" for the Orbital Flight Test-2 (OFT-2) mission to the International Space Station. (Image credit: Boeing via collectSPACE.com)

In the game Kerbal Space Program, if the rocket you design doesn't reach its intended destination, you have to return to the virtual hangar to try to fix the problem.

The first real-life flight of a Kerbal, the green humanoid aliens that populate the video game, should be on the second attempt by Boeing.

One of the original Kerbonauts in the game is known as "Jeb", and he is the first to actually be launched into space. The day after launching on a United Launch Alliance (ULA) Atlas V rocket, Jeb flew as the "zero-g indicator" for Boeing's Starliner Orbital Flight Test-2 (OFT-2), which arrived at the space station on Friday.

Live updates: Boeing Starliner Orbital Flight Test 2 mission to ISS

Related: Boeing's Starliner OFT-2 test flight  in amazing photos 

Boeing's Starliner Orbital Flight Test-2 zero-g indicator, a plush Jeb from the game Kerbal Space Program, is seen through a window into the space capsule. Jeb is seated next to "Rosie the Rocketeer," an anthropometric test device.

Boeing's Starliner Orbital Flight Test-2 zero-g indicator, a plush Jeb from the game Kerbal Space Program, is seen through a window into the space capsule. Jeb is seated next to "Rosie the Rocketeer," an anthropometric test device. (Image credit: Boeing via collectSPACE.com)

In between flights, Boeing engineers did a full-up test similar to what Kerbal Space Program players do between attempts. The end result is mission success.

The Starliner's uncrewed capsule successfully docked to the space station after being kept a secret. He was left for the station's crew to discover that he was floating on the end of a tether.

A Boeing spokesman told collectSPACE.com that the Kerbonaut was chosen to represent the enthusiasm many on the Starliner engineering team have for the game, as well as the science, technology, engineering and mathematics (STEM) lessons it impart to players.

Private Division, the game's publisher, provided the plush doll. The company sells identical Jeb dolls on its website.

The company wrote that if you are playing Kerbal Space Program or doing anything really, you need the perfect co-pilot. He is still just as brave.

From video game Kerbalnaut to real-life zero-indicator, Kerbal Space Program's Jeb is seen on Boeing's CST-100 Starliner.

From video game Kerbalnaut to real-life zero-indicator, Kerbal Space Program's Jeb is seen on Boeing's CST-100 Starliner. (Image credit: Boeing via collectSPACE.com)

The custom of zero-g indicators was started by the Soviet-era cosmonauts. Zero-g indicators have become a part of U.S. commercial spaceflights as NASA astronauts began flying with their Russian counterparts.

The OFT-1 was launched with a spacesuit-clad Snoopy doll as its zero-g indicator. Boeing released a video of a beagle floating above his seat on the capsule, which was on its way to the space station.

After several days at the station, the crew will close the hatch to the Starliner and send him home. The Starliner will land in New Mexico if the weather is good.

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