Mission: Build a replica of the OSIRIS-REx spacecraft and successfully return an asteroid sample to Earth. That's the challenge OSIRIS-REx Project Scientist Jason Dworkin of NASA's Goddard Space Flight Center in Greenbelt, Maryland presented to fans of the popular online computer game "Kerbal Space Program" (KSP). The game is set on Kerbin, a fictional Earth-like planet that is home to enthusiastic space-faring creatures known as Kerbals.

Players are in charge of Kerbin's burgeoning space agency, and can build rockets and perform space exploration missions using realistic physics and orbital mechanics.

Dworkin challenged players to use the virtual tools and supplies provided by the game to construct their own OSIRIS-REx spacecraft (also known as the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer), collect an asteroid sample, and return it safely to Kerbin. In reality, OSIRIS-REx will travel to a near-Earth asteroid known as Bennu to harvest a sample of surface material and return it to Earth for study.

Sounds easy, right? Well, while you don't need a physics degree to understand the game, KSP comes with its own set of weights and requires accurate measurements to successfully launch rockets. If your in-game rocket is too heavy, it will never get off the ground.

"I built a few different versions of my own OSIRIS-REx, but I couldn't launch the spacecraft using realistic masses," said Dworkin, chief of the Astrochemistry Laboratory NASA Goddard. "My spacecraft was way too heavy and the center of thrust was wrong. When I tried to launch it, it spun up and broke into pieces."

Dworkin, who has played the game since 2011, posted his attempts at re-creating the OSIRIS-REx spacecraft in the game on a KSP community forum and challenged players to try it themselves. He provided them with some technical information about the spacecraft and mission, as well as visuals of the actual OSIRIS-REx to give them a sense of what it should look like.

Players immediately jumped at the opportunity, sharing their successes and failures with Dworkin.

"I am very excited to see [an] ... OSIRIS-REx team member among the KSP forum ranks," said KSP gamer Matuchkin in the game's forum.

The community's response came as a surprise to Dworkin.

"I'm blown away by how much interest this challenge has received," Dworkin said. "Here is a community of people that is enthusiastic about space and wants to learn the science of spaceflight."

This is not the first time NASA and KSP have crossed paths. NASA reached out to Squad, the company that develops KSP, in 2013 to implement its Asteroid Redirect Mission into the game. Players can use NASA-based technologies to perform their own asteroid redirect mission.

While Dworkin's challenge to players is not an official partnership with Squad, the company said it would be interested in working with NASA again.

"The OSIRIS-REx mission could provide some interesting game mechanics," said Kasper Nahuis, KSP community lead who handles marketing and public relations. "Seeing NASA folks directly engage with our community is an incredible thing;."