Geostationary Lightning Mapper
The Geostationary Lightning Mapper is a weather-satellite camera that records lightning and also detects bright fireballs.
The Geostationary Lightning Mapper, or GLM, is an instrument on NOAA's GOES weather satellites, which hover above fixed points on the equator about 36,000 kilometres up. Since 2017 it has watched the Americas and surrounding oceans, recording flashes of light at about 500 frames per second to map lightning.
Bright fireballs produce a flash that the instrument also records. Scientists have learned to pick these out from lightning by their shape and movement. GLM has detected thousands of fireball candidates, including events over the Caribbean and South America. In some cases, its data helped locate where meteorites fell.
Because GLM watches continuously, day and night, it provides a fairly unbiased count of bright fireballs over a large part of the planet. Combined with ground cameras, infrasound and other satellites, it helps estimate the flux of metre-sized meteoroids, the sizes most likely to drop meteorites.
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