Invisible Black Holes: Planets or Something Else? ⚡ экспресс
Scientists examined exoplanet search data from radial velocity (stellar wobbles) and microlensing (gravitational light bending) to hunt for primordial black holes (PBHs) — hypothetical remnants from the early Universe with planet-like masses. By eliminating objects seen directly or via transits (definitely planets), they spotlighted several PBH candidates, such as Kepler-21 Ac and Wolf 1061 d, plus two microlensing events. Like invisible dancers, their presence is betrayed only by gravitational influence. Future images will sort the real from the imposter.
A star dancing without a visible partner — that’s how astronomers perceive its wobble. Doppler shift usually reveals a planet, but sometimes the companion remains invisible. Then it could be a primordial black hole — a planetary-mass object born in the early Universe. Unlike ordinary planets, such a hole neither reflects light nor blocks the star (no transit).
Sifting through data on thousands of exoplanet candidates, scientists identified six objects that reveal themselves only through gravity. Among them are companions of the stars Kepler-21, Gliese 686, and four others. Two cases of brief light bending from distant stars (microlensing) are also suspicious.
The gravitational dance gives away both a planet and a black hole equally. Telling them apart may rely on Hawking radiation: tiny holes evaporate faster and could emit a faint signal. If confirmed, these invisible partners would become the key to dark matter — the mysterious substance that perhaps makes up most of the Universe.
🎯 A primordial black hole with Earth’s mass would fit inside a grape — its diameter is just 9 millimeters.