The US Space Force 'X-37B Space Plane' will be launching its sixth mission and will be in orbit until 2022.

One of the most mysterious X-projects that is not well known will be launched again on Sunday but more secretive equipment is onboard the spaceplane. Compared to other spacecraft, the X-37B is solar powered with remote-controlled fight capacity that needs no pilots or crew.

Officials governing the program are not mentioning the duration of the mission, but it will stay in orbit longer. This was confirmed by Jim Chilton to be one of the longest missions it will embark on.

Before this upcoming mission, a previous one lasted for 24 months, before the space plane made a touchdown at NASA's Kennedy Space Center a year ago. Details of the two-year mission are kept in black no details were given.

A brief was given by the military for the first time and was shared publicly to know the space plane's mission before the orbital flight.

Taking the payload will be an Altas V rocket that is powered by liquid fuel, and inside the X-37B are three payload sets for the three experiments in weightless space.

One of these experiments is turning the sun's power into a form of radiofrequency microwave energy, which is directed to be received by facilities on Earth. Military posts will serve as receivers on the ground.

With the generation of solar power, materials for the systems will be examined in the void of space, also the effects of outer space radiation on seeds for NASA.

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The craft has a striking similarity to the older manned NASA Shuttles, a fraction of their size that is 29 feet in length. Include in the version used for this mission payload is extra space for experiments, one is for NASA, and the other is the U.S. Naval Research Laboratory, carrying the extra loadout is one the biggest for the X-37B.

Two of these reusable space planes are part of the Air Force, though the Space force owns them as well. Both unmanned spacecraft are to be parked at the old space shuttle hangar bay at Kennedy.

Chilton said the X-37B and the old space shuttle share similarities in shape and where they are stored till use. One of the most well-kept secrets of the US Air force and now part of the space force, from the first flight in 2010 when no other nation has this asset in their inventor. These secret planes have been active for 2,865 days (orbit) on Sunday.

Chilton mentioned that a total of fewer than eight years in orbit with 1 billion miles, that was logged by space plane on the launching broadcast.

Last March, it took a national security satellite up in space. But the mission was stalled by bad atmospheric condition and only the second mission of the Space force. An Atlas V rocket was the launch vehicle, with success declared after 1.5 hours from liftoff. The launch was dedicated to all the pandemic front liners on Sunday

The two Air Force X-37Bs are alternating with one under refurbishing. Both have solar cells with lithium-ion cells, its orbit will be 200 miles up. Missions of the space planes are longer than standard ones.

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