Here's everything we know about the mysterious Air Force plane that just landed after 2 years in spaceBusiness Insider, May 8, 2017, Christopher Woody
The US military's X-37B space plane landed at NASA's Kennedy Space Center on Sunday, ending its record-breaking 718-day orbit with a sonic boom during its first landing in Florida.
The US Air Force has two X-37B Orbital Test Vehicles, which it calls its "newest and most advanced reentry spacecraft."
At 29 feet long and with a 14-foot wingspan, the planes are about one-quarter of the size of NASA's retired space shuttles and have a cargo bay about the size of a pickup truck's.
The first X-37 program started in 1999, and the X-37B first flew in April 2010, returning after eight months.
The next mission, launched in March 2011, was 15 months, and the third mission, in December 2012, lasted 22 months.
"Our team has been preparing for this event for several years, and I am extremely proud to see our hard work and dedication culminate in today's safe and successful landing of the X-37B," Air Force Brig. Gen. Wayne Monteith, the commander of the 45th Space Wing, said in a release.
The most recent X-37B mission, launched in May 2015, brings the orbital test vehicle program to a total of 2,085 days spent in orbit.
Amateur astronomers have spotted the craft through telescopes and observed it at relatively low altitudes — a little less than 200 miles, according to some, which is lower than the International Space Station.
What the X-37Bs have done during those 2,085 days in orbit is less clear, however.

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