The Tibet Air Shower Array has detected extremely high-energy photons from the Crab Nebula, which is some 6,500 light-years away from Earth..
Light Showers
The Tibet Air Shower Array is located about five kilometers (3.1 miles) above sea level, and this high altitude makes it an ideal spot to gather data on the subatomic particles that shower the Earth after high-energy cosmic rays blast the planet’s atmosphere.
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