USA’s secretive X37B ‘spy plane’ reaches record breaking 719 days in orbit – but we STILL don’t know its real mission
A MYSTERIOUS US spacecraft has broken the record for its longest flight in orbit – but we still have no idea what it's doing up there.
The secretive X37B space plane has now been quietly gliding above our heads for 719 days straight, topping its previous record set in 2017.
The unmanned vehicle is about the size of a bus and is thought to carry out intelligence operations from space, though its mission is top secret.
Some have speculated the experimental plane is loaded with spy cameras, or weapons that can take out enemy satellites.
The US Air Force is cagey about the mission, simply stating it "supports technology risk reduction, experimentation and operational concept development."
On Tuesday, the X37B hit 718 days in orbit during what is the craft's fifth mission, dubbed Orbital Test Vehicle Five (OTV-5).
That means it's now on its longest ever flight, topping the 717 days, 20 hours and 42 minutes it managed during OTV-4, the plane's fourth mission, which ended in May 2017.
OTV-5 launched in September of that year, with a liftoff atop a SpaceX Falcon 9 rocket
It's unclear what the secretive spy vessel is doing up there now, or what it has done on past flights
The Air Force has at least two X37Bs, both built by aerospace giant Boeing.
The plane began as a Nasa project in 1999, but was transferred to the US Department of Defense just five years later.
It operates in a low-Earth orbit, but the nature of its missions remains a secret.
In 2012, it was speculated that the USA was using it to spy on China's Tiangong-1 space station module.
But this was later refused by the US Air Force, saying the two crafts' respective orbits didn't make for practical surveillance fly-bys.
USA's X37B space plane missions – when did the secret operations take place?
Here's the full list so far...
- OTV-1 – Launched on April 22, 2010 (Duration: 224 days and 9 hours)
- OTV-2 – Launched on March 4, 2011 (Duration: 468 days and 14 hours)
- OTV-3 – Launched on December 11, 2012 (Duration: 674 days and 22 hours)
- OTV-4 – Launched on May 20, 2015 (Duration: 717 days and 20 hours)
- OTV-5 (ongoing) – Launched on September 7, 2017 (Duration: 668 days and 13 hours)
It has also been rumoured that the USA is using the space plane to test spy sensors, studying how they fare against radiation and other space hazards.
And despite the advanced technology on board, the plane is tiny – and therefore hard to photograph.
It has a wingspan of 14ft 11in and a height of 9ft 6in, boasting a maximum take-off weight of 11,000lb.
It rockets around Earth in a low orbit at 17,426mph, and takes about 270 days to circle Earth.
And there's not a single crew member on board: the craft is entirely robotic, relying on computer systems for navigation and operation.
We're expecting a sixth mission for X37B to begin later this year, although it's not clear when.
While 719 days is impressive, the X37B is nowhere near the all-time space flight record.
Commercial satellites regularly top five years in orbit, while Nasa's Voyager probes are still beaming data back to Earth four decades after they launched.
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In other space mystery news, scientists recently determined that a strange space object called Oumuamua is probably not an alien probe.
An Apollo astronaut has admitted that he nearly died ‘trying to do a high jump’ on the Moon in 1972.
And, there may have been a breakthrough in the search for alien life as scientists pinpoint exact location of mysterious fast radio burst that ‘could be signal from ET’.
What do you think the plane is looking for? Let us know in the comments!
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