March 29, 2024

Finding Exoplanets in Debris Disks

Astronomers studying the particles disk around the star HD 206893 have actually imaged a large space in the disk extending from about 50 to 185 au from the star. They are common: more than about a quarter of all main-sequence stars have debris disks and, since these disks can be tough to discover, it is most likely that the portion is even greater. Current instruments are just able to identify debris disks in systems that are at least an order of magnitude more luminous than the disk produced by the solar systems Kuiper Belt (the area extending from the orbit of Neptune at about thirty huge units out to about fifty au).

Recommendation: “Resolving Structure in the Debris Disk around HD 206893 with ALMA” by Ava Nederlander, A. Meredith Hughes, Anna J. Fehr, Kevin M. Flaherty, Kate Y. L. Su, Attila Moór, Eugene Chiang, Sean M. Andrews, David J. Wilner and Sebastian Marino, 6 August 2021, The Astrophysical Journal.DOI: 10.3847/ 1538-4357/ abdd32.

An artists impression of a stars dirty particles disk, believed to be produced when asteroids or other planetesimals clash and fragment. Astronomers studying the particles disk around the star HD 206893 have actually imaged a wide space in the disk extending from about 50 to 185 au from the star. After modeling the system, they conclude it contains a 1.4 Jupiter-mass planet orbiting about 79 au from the central star. Credit: NAOJ
When asteroids or other planetesimals clash and piece, Debris disks around main-sequence stars are rare belts of dust believed to be produced. They prevail: more than about a quarter of all main-sequence stars have debris disks and, since these disks can be tough to discover, it is likely that the portion is even higher. Current instruments are only able to detect particles disks in systems that are at least an order of magnitude more luminous than the disk produced by the solar systems Kuiper Belt (the area extending from the orbit of Neptune at about thirty huge units out to about fifty au).
The dust in particles disks is worthy of study in its own right however likewise offers a chance to trace the residential or commercial properties of planetary systems. A planet in a particles disk can create such a gap, and measurements of the spaces dimensions can thus be utilized to deduce the mass of the world– a crucial exoplanet parameter that is otherwise hard to obtain.
CfA astronomers Sean Andrews and David Wilner were members of a group that utilized ALMA to study the recognized debris disk around the star HD 206893 about 135 light-years away from us. The ALMA images spatially resolve the disk– it extends from about 50 -185 au– and the astronomers find proof for a space extending from about 63– 94 au.