How a baby planet drinks gas: a new discovery ⚡ экспресс
Using MUSE on the VLT, astronomers studied the protoplanet AB Aur b in the Hα line and captured a unique spectrum: short-wavelength emission (shifted by -100 km/s) and long-wavelength absorption (+75 km/s). This resembles an inverse P Cygni profile — a signature of infalling cold gas, typical of accreting stars. AB Aur b is the second protoplanetary system detected in Hα, and the first with such a profile, like a 'whirlpool' in the spectrum. The nature of the signal is still unclear: it could be accretion, reflected light, or something else.
The forming exoplanet AB Aur b behaves like a hungry baby: it greedily sucks in gas from the surrounding cosmic cloud. Astronomers using the VLT telescope caught it in the act in the AB Aurigae star system. They studied the light from heated hydrogen near the planet, spreading it into colors. The picture turned out to be double: part of the light seems to "run away" from us, part is absorbed by the cloud of infalling material. In spectroscopy, such a pattern is called a reverse P Cygni profile: cold gas rapidly falls onto a hot body. Previously, this was only seen around stars, but now—around a planet embryo. The infall speed is 100 kilometers per second: such a flow would take just an hour to travel from Earth to the Moon. This discovery provides a live snapshot of the birth of gas giants like Jupiter and will help refine how often systems like our Solar System emerge in the Universe.
🎯 In an hour, the falling gas covers the distance from Earth to the Moon.