Paul Allen and his Stratolaunch team quietly built the 500,000 pound aircraft in California.
The Stratolaunch was rolled out for the first time today in Mojave, about 90 miles north of Los Angeles.
The aircraft will carry small launch vehicles that deploy satellites into low-earth orbit.
Satellites in low-earth orbit circle the earth in less than two hours at an altitude of up to 1,200 miles.
The wingspan is longer than a professional football field and measures about 240 feet from nose to tail.
It’ll be tested over the next couple of years before it’s ready for a launch.