The Mystery of Mysterious Green Lasers Finally Solved by NASA

TL;DR
Motion-detecting cameras outside a museum in Japan captured green laser beams in the sky, which were later identified as being emitted by NASA's ICESat-2 satellite. The satellite uses lasers and a lidar sensor to measure ice sheet elevation, sea ice thickness, and land topography on Earth. The laser beams are typically difficult to spot from Earth, but on this occasion, the clouds scattered the laser light, making it visible to the museum's cameras. This is the first time the satellite's laser beams have been caught on camera.
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