Microsoft co-founder Paul Allen has spent the last six years working on a giant aircraft capable of launching rockets to space. Today, his company Stratolaunch Systems literally rolled that plane out of its hangar in the Mojave Desert for the first time ever.

Dancer Megan changes costume as she performs in the review “Feerie” at the Moulin Rouge in Paris, France, July 3, 2018. Each show requires 1,000 outfits, all crafted in the workshops that have been supplying the Moulin Rouge for decades. Each dancer has to make between 10 and 15 costume changes per show, with about 90 seconds to complete each one before they have to be back out on stage. (Photo by Philippe Wojazer/Reuters)

A mahout splashes water on his elephant in the river Sabarmati on a hot summer day in Ahmedabad, India, May 20, 2015. (Photo by Amit Dave/Reuters)

U.S. Army soldiers with the 1st Battalion, 501st Infantry Regiment deployed to Combat Outpost Sabari, Afghanistan scan their area as they begin a multi-day air assault mission near the Pakistani border of eastern Afghanistan's Khost province May 2, 2012. (Photo by Staff Sgt. Joshua L. DeMotts/U.S. Air Force)

“Pivo”, Nissan's concept car is introduced at Nissan's Gallery on September 30, 2005 in Tokyo, Japan. “Pivo” is an electric car in which the direction of the cabin moves 180 degrees, therefore, when making a turn in a different direction, it simply needs to move the cabin without moving the car. (Photo by Koichi Kamoshida/Getty Images)

Thor, Virginia Tech College of Engineering, Robotics and Mechanisms Laboratory, tries to connect the hose to a firehose connection during the hose task at the Homestead-Miami Speedway, Friday, December 20, 2013, in Homestead, Fla. (Photo by Alan Diaz/AP Photo)

Mangli Munda poses on her wedding day with a stray dog in Jharkhand, India on August 30, 2014. An 18-year-old Indian girl has married a stray dog as a part of a tribal ritual designed to ward off an evil spell. Village elders hastily organised the wedding between Mangli Munda and the canine as the teenager is believed to be bringing bad luck to her community in a remote village in Jharkhand state. Mangli's father Sri Amnmunda agreed and even found a stray dog named Sheru as a match for his daughter. And while Mangli was a hesitant bride, she believes that the ceremony will help ensure that her future human husband will have a long life. (Photo by Barcroft Media/ABACAPress)

Katie Francis, a member of the Difficult Access Team from Wiss, Janney, Elstner Associates, inspects a gargoyle while rapelling down one of the north tower on the west front of the National Cathedral while looking for damage from August's magnitude 5.8 earthquake and high winds from Hurricane Irene October 17, 2011 in Washington, DC. DAT members used cameras, cell phones and iPad computers to record places on the cathedral's west front where damage was apparent. (Photo by Chip Somodevilla/Getty Images)