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A 22W laser used for adaptive optics on the Very Large Telescope in Chile. A suite of similar lasers could be used to cloak our planet’s transit around the Sun. (credit: ESO/G. Hüdepohl)
We could use lasers to conceal the Earth from observation by an advanced extraterrestrial civilization by shining massive laser beams aimed at a specific star where aliens might be located — thus masking our planet during its transit of the Sun, suggest two astronomers at Columbia University in an open-access paper in Monthly Notices of the Royal Astronomical Society.
The idea comes from the NASA Kepler mission’s search method for exoplanets (planets around other stars), which looks for transits (a planet crossing in front a star) — identified by a tiny decrease in the star’s brightness.*.
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