The following submission statement was provided by /u/upyoars:

> Scientists have proposed another use for the world's largest gravitational wave observatory: scanning for the ripples in space-time left in the wake of gargantuan alien spaceships.

> Now, new calculations published Dec. 5 to the preprint database arXiv(opens in new tab) suggest that the U.S.-based Laser Interferometer Gravitational-Wave Observatory (LIGO) can look beyond conventional sources for these space-time ripples. Colossal alien spacecraft traveling at high speeds, or pushed along by warp drives, would also produce the telltale vibrations.

> The LIGO detector spots gravitational waves from the tiny distortions they make in space-time as they pass through it. Made up of two intersecting L-shaped detectors — each with two 2.48-mile-long (4 kilometers) arms and two identical laser beams inside — the experiment is designed such that if a gravitational wave passes through Earth, the laser light in one arm of the detector will get compressed while the other expands, creating a tiny change in relative path lengths of the beams arriving at the detector.

> To be detectable by LIGO, an alien mothership would need to weigh roughly the same as Jupiter, travel at one-tenth the speed of light, and be within 326,000 light-years of Earth.

> The physicists have noted that advanced alien warp drives would create gravitational wave patterns that would be distinguishable from natural sources and that, if detected, these alien waves could even provide humans with clues about how to reverse engineer the technology.

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