Astronomers using the VLT's SPHERE instrument were able to obtain sufficiently clear images of the circumstellar disks around young stars close to us, which allows us to understand their evolution and the mechanisms of planetary formation. The articles will be published in the journals Astronomy & Astrophysics and Astrophysical Journal, a summary of the results of the work is described in a press release on the ESO website.
Planetary systems, such as our solar system, are formed from a circumstellar disk around a young star. It usually consists of dust, gas, asteroids, planetesimals, and debris that form when bodies collide in the disk. Circumstellar disks come in a wide variety of shapes and sizes, with some showing bright or dark rings, layers, or other features. The study of such objects allows us to understand the mechanisms governing the formation of stars and planetary systems around them, as well as to reveal the relationship between the properties of the disk and the formation of planets in it.
The new papers present images of circumstellar disks obtained with the SPHERE receiver mounted on the VLT telescope in Chile. Its main purpose is to obtain images of exoplanets by the direct imaging method, for this purpose the light from the star is blocked. The same technique also makes it possible to obtain images of circumstellar disks with good resolution, which makes it possible to reveal the details of their structure. Most of the images were obtained as part of the DARTTS-S (Disks Around T Tauri Stars with SPHERE) survey, the distance to the observed objects ranges from 230 to 550 light years from Earth.
The eight young stars that have observed circumstellar disks belong to the class of very young (less than ten million years old) T Tauri variable stars. The sizes of these disks range from 80 to 400 astronomical units. Another edge-on disk is located around the edge-on disk around the M-class red dwarf GSC 07396-00759, which is part of the binary star system. This disk appears to be older than a similar disk around a T Tauri companion star, although the stars are the same age. So far, this difference has no clear explanation and is another reason for observing such objects.
Alexander Voytyuk
