U.F.O. Stalks N.A.S.A._Space Shuttles STS_37, 39, 51

Sphere UFO Encounter by multiple N.A.S.A. Space Shuttles STS_37, 39, 51

See 90 degree turns, Materialization + De-Materialization, and
U.F.O.'s Traveling at hypersonic Speeds !
That's Mach_10 - Mach_25 (7,673 -19,183 mph) respectively.

New York Times May 27, 2019 Reported the following:
Navy Pilots Report Unexplained Flying Objects
Navy Pilot, Lieutenant Graves said: "It looked like a sphere encasing a cube. What was strange, the pilots said, was that the video showed objects accelerating to hypersonic speed, making sudden stops and instantaneous turns — something beyond the physical limits of a human crew".
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From Website: Space.com
NRO also wanted polar shuttle missions, since POLAR MISSIONS MAKE IT POSSIBLE TO SEE THE EARTH'S ENTIRE SURFACE BELOW

Entire surface Below ??

NASA's space shuttle was the world's first reusable spacecraft. It launched like a rocket and returned to Earth like a glider. It was designed to carry large payloads — such as satellites — into orbit and bring them back, if necessary, for repairs.

Following test flights using the shuttle Enterprise (which did not go into space), the first space shuttle mission, STS-1, launched on April 12, 1981, aboard the orbiter Columbia. The last shuttle to fly was Atlantis on the STS-135 mission in July 2011. The space shuttle program suffered two major disasters — on Jan. 28, 1986 (Challenger) and Feb. 1, 2003 (Columbia); 14 astronauts died on the two missions.

Joint operations

In the early days of the space shuttle program, some of the missions were run jointly by NASA and the military. This was in part because the National Reconnaissance Office had successfully requested the shuttle's payload bay — the part of the shuttle that carried satellites be carried into space — be enlarged to accommodate large military satellites, according to Air & Space Magazine.

The Air Force went so far as to create a launch pad in Vandenberg, California for polar-orbiting space shuttle missions.....

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