Brian C. Lacki

The Vera Rubin Telescope will discover thousands of interstellar visitors. To tell a natural object from a relic of another civilization, scientists have developed a protocol: they’ll study the light 'fingerprints' of these guests.

Supermassive black holes heavier than a trillion Suns have an unexpected property: their shadow doesn't shrink with distance—it grows. This helps astronomers set strict limits: black holes with masses over a hundred million billion Suns simply cannot hide in the observable Universe.

Calculations show that tiny artificial particles could cross interstellar space and survive in the lunar soil. Sunlight filters out the unsuitable ones, and on the Moon, they don't burn up in an atmosphere. Even a handful of regolith could tell us how often technological civilizations arose in the G