The inside of a dusty disk around a nearby red dwarf star has been captured by NASA’s James Webb Space Telescope. With these observations, the previously observed disk has been imaged for the first time at these infrared light wavelengths, revealing a disk-like disk never seen before. They also offer hints about the disc’s composition.
Located 32 light-years away in the southern constellation of Microscopium, the galaxy AU Microscopii, or AU Mic, is nearly 23 million years old. The formation of the planet has ended, as that process typically takes less than 10 million years.
There are two planets within this galaxy. The dust disk is the result of collisions between remnant planetesimals — a more massive equivalent of the dust in our solar system that creates a phenomenon known as zodiacal light.
The team examined AU Mic using Webb’s Near-Infrared Camera (NIRCam). They analyzed the area near the star with NIRCam’s coronagraph, which reflects its bright light. The researchers were able to track the disk as close to the star as five astronomical units (460 million miles), which is similar to Jupiter’s orbit in our solar system, using the NIRCam photos.
Images were captured by the observation program at wavelengths of 3.56 and 4.44 microns. The team found that the disk was “bluer,” or brighter, at shorter wavelengths, indicating that it likely contains a lot of particulate matter that is effective at scattering light at shorter wavelengths.
Kellen Lawson of NASA’s Goddard Space Flight Center, lead author of the study, said: “Collisions of planetesimals continuously replenish a debris disk. By studying it, we gain a unique insight into the recent dynamical history of this system.”
Josh Schlieder of NASA’s Goddard Space Flight Center, principal investigator for the observation program and co-author of the study, said: “This system is one of the few examples of a young star, with known exoplanets, and a debris disk close enough and bright enough to study holistically using Webb’s uniquely powerful instruments.”
“Our first look at the data far exceeded expectations. It was more detailed than we expected. It was brighter than we expected. We found the drive closer than we expected. We hope that as we dig deeper, there will be even more surprises that we didn’t predict.”
This finding is consistent with the results of previous studies, which showed that the radiation pressure of AU Mic – unlike that of more massive stars – would not be strong enough to eject fine dust from the disk.
lawson said, “This is the first time we have the sensitivity to directly observe broad-orbiting planets that are significantly less massive than those of Jupiter and Saturn. This is new, uncharted territory for direct imaging around low-mass stars. .”
