Quote:Human satellites typically don't carry optical light sources, with rare exceptions like communication lasers or spacecraft thrusters. So any bright flashes or streaks detected within Earth's shadow could potentially indicate something more exotic.

The researchers analyzed images from the Zwicky Transient Facility (ZTF), a telescope in California that systematically surveys the sky for changing objects. They examined over 200,000 images, specifically focusing on those captured within Earth's shadow.

Their automated search system, called NEOrion, detected thousands of candidates, including mysterious streaking objects and point source flashes. Most turned out to be meteors, aircraft, or known asteroids.

However, one intriguing case emerged; an uncatalogued object moving much faster than typical asteroids and not found in any existing space object databases. Sadly, however, the team was unable to confirm what it was, so it still remains a mystery.

https://www.sciencealert.com/scientists-are-using-earths-shadow-to-hunt-for-alien-probes