How a Swallowed Planet Spun Up a Star ⚡ экспресс
Scientists studied the star GJ 504, which looks too young for its age: it spins fast and has a strong magnetic field. It turns out it might have swallowed a nearby giant planet, giving it a jolt of energy—like a morning coffee. Could our Sun ever meet a similar fate?
The star GJ 504, a twin of our Sun in age, behaves like a true figure skater: it completes a rotation in 3.4 days, shining with X-ray light. Usually, stars of the Sun's age spin sluggishly, but this one seems to have received a cosmic doping.
The secret was revealed by modeling. Light analysis (spectroscopy) showed that normal braking by the stellar wind couldn't have slowed it down. The only explanation: in the past, the star swallowed a exoplanet the size of Jupiter. This 'dance partner' transferred its orbital momentum, and the star spun up like a figure skater after a lift. Without that, it would rotate lazily—a full revolution per month.
A similar 'dancer' has been found at HD 75332—it seems celestial choreography is more common than expected.
🎯 The star GJ 504 completes a full rotation in 3.4 days—seven times faster than our Sun.