Astronomers discover glowing gasoline round a baby planet
Radio telescopes just like the Atacama Large Millimeter/submillimeter Array (ALMA) have captured photographs of glowing disks of fabric round younger stars.
This picture exhibits one such circumstellar disk across the star AS 209, roughly 395 light-years away within the constellation Ophiuchus.
The gaps in the disk are where nascent planets are being born, sweeping up gas and dust onto their surface as they orbit.
Until recently, only two such circumplanetary disks (CPDs) had ever been spotted and confirmed.
Now, astronomers have found what may be a 3rd CPD — and for the first time, they think they have detected not its dust, but the much fainter emission from gas in the disk.
By using ALMA, the team were able to identify light emitted by carbon monoxide gas coming from an otherwise empty gap in the disk of AS 209.
What made the gasoline planet this nascent planet seen is the sheer measurement of the forming planet and its distance from its host star...
Previous CPDs had been solely about one astronomical unit (AU) in diameter, or the typical Earth-Sun distance.
The CPD in AS 209 is much larger, perhaps as large as 14 AU across, and orbits 200 AU from its host star — over 5 times the average distance of Pluto from the Sun.