Museum curator and Japanese astronomer Daiichi Fujii noticed something anomalous among the many motion-sensing cameras he installed last September: three bright green lights flashing across the sky.

After studying the images and comparing them to orbital data, Fuji identified the party responsible: the Ice, Cloud and Earth Satellite 2, or ICESat-2, which flew over Japan that night.

According to satellite instrument expert Tony Martino, this is the first time the team has seen images of the instrument’s laser pulsating across the sky.

“ICESat-2 seems to have been almost straight forward [Fujii]Martino at NASA said: launch. “To see a laser, you have to be in the right place, at the right time, and you have to have the right conditions.”

ICESat-2 It was launched in 2018 and is used to measure the elevation of Earth’s surfaces. It is basically a spatial structure Lidar DigitizerSimilar to those used by archaeologists Discover ancient sites lost to natural features such as forest growth.

This video was taken on September 16, 2022. It shows three lines flashing across the sky against a background of dispersing clouds. Upon closer inspection, Fuji realized that the green streaks that appeared to be abstracted between the clouds were pulsating in time (just above the center of the video frame, if you want to identify them yourself).

Guessing it was a satellite, Fuji checked which spacecraft was flying the cameras that night. Lo and behold, ICESat-2 has emerged as a possible culprit.

NASA has released ICESat-2’s perspective of Japan to show the other side of the encounter. The data chart shows a satellite measurement of cloud layers in Japan and the topography of the country.

According to NASA, the ICESat-2 rocket is launched 10,000 times per second. The satellite has already imaged from Earth, but not its laser pulses, which must observe unique atmospheric conditions.

Clouds over the Hiratsuka City Museum that night scattered the laser light visible to the Fuji cameras, but there weren’t enough clouds to block the light.

So the next time you see a bright light in the sky, it won’t be a meteor or an alien. They can be human tools to monitor what is happening in the field.

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