A SpaceX Falcon 9 rocket launches a military X-37B reusable space plane from Cape Canaveral in Florida on a clandestine mission for the United States Air Force (USAF). One of USAF's two X-37Bs landed in May after 500 days in orbit on a secret mission.
Market Watch reports that the United Launch Alliance, owned jointly by Boeing and Lockheed Martin, launched the four previous X-37B missions. It notes that Elon Musk's Space Exploration Technologies Corp worked for years to win military contracts for its Falcon 9 rockets, and won its first Pentagon contract in Apr 2016.
The robotic vehicle resembles NASA's famous space shuttle but is much smaller, according to Space.com. It is some 29 feet long and 9.5 feet tall, with a wingspan just less than 15 feet. Like the space shuttle, the solar-powered X-37B space plane launches vertically with the aid of a rocket, and cruises back to Earth for a runway landing. It is designed to operate at altitudes ranging from 110 to 500 miles.
An X-37B fact sheet produced by USAF states that the primary objectives of the X-37B are "reusable spacecraft technologies for America's future in space and operating experiments which can be returned to, and examined, on Earth."
Since the X-37B first flew in April 2010, the test vehicle program has spent a total of 2,085 days in orbit.
Date written/update: 2017-07-12