How a baby planet drinks gas: a new discovery ⚡ экспресс
Analysis of AB Aurigae observations with MUSE/VLT in the Hα line revealed emission from the protoplanet AB Aur b. Emission was recorded at 6558.88–6560.13 Å (shift -100 km/s) and absorption at 6562.8–6565.1 Å (+75 km/s). The spectrum does not match the star, disk, or protoplanets PDS 70 b and c; instead, it resembles an inverse P Cygni profile—an indicator of infalling cold gas in accreting T Tauri stars. Other sources of the signal unrelated to accretion cannot be formally ruled out. AB Aur b is the second system detected in Hα and the first with an inverse P Cygni profile. Future modeling and new optical data are needed to determine whether the signal is caused by accretion onto the planet, scattered light, or another mechanism.
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.