The James Webb Space Telescope has peered for the first time into a planet-forming disk of dust surrounding a nearby star, a development that promises to redouble the search for exoplanets.
using James Webb Space Telescopenear infrared camera (nirkam), a team of astronomers led by Kellen Lawson, a postdoctoral fellow at NASA’s Goddard Space Flight Center, has been observing the ocean red dwarf known star AU Microscope or AU Mic.
Red dwarfs are rather unassuming stars Which make up the largest number of stars in our galaxy Milky Way. Most of the time, red dwarf stars are too dim to see in visible light, which is why observing them at heat-bearing infrared wavelengths, the ones Webb specializes in, is useful. Astronomers have known that AU Mic is surrounded by a disk of gas and dust and have previously detected two outer planets It orbits the star thanks to the periodic dimming of the star caused by the transit of planets in front of the star, which was observed by NASA’s TESS Exoplanet Hunter.
Related: The first year of the James Webb Space Telescope has alienated astronomers
Various teams have made attempts to peer into the disk using ground-based telescopes in addition to Webb’s predecessor, Hubble Space Telescope. However, these telescopes, which mostly observe visible light, can’t match Webb’s dust-penetrating capabilities.
“Our first look at the data far exceeded expectations,” said Josh Schleider, co-author of the study. statment (Opens in a new tab). “It was more detailed than we expected. It was much brighter than we expected. We discovered the disk sooner than we expected. We hope that as we dig deeper, there will be some surprises we didn’t expect.”
Infrared light has longer wavelengths than visible light and is less scattered by dust, providing a window into these blocked regions of light. being. The team was able to study the disk thanks to a coronal vertebra mounted on NIRCam, which can block the star’s light, allowing astronomers to search for very faint objects as close as 5 astronomical units from the star (one astronomical unit is equal to the distance between a star and a star). the sun And a land That’s 460 million miles or 740 million kilometers).
“This is the first time that we really have the sensitivity to directly observe planets with wide orbits that are significantly less massive than Jupiter and Saturn,” Lawson said in the statement. “This is really new, uncharted territory in terms of direct imaging of low-mass stars.”
It is very difficult to observe exoplanets directly because they are much lighter than the stars they orbit. Webb made headlines in september when she He photographed the first planet outside the solar system directlyOne of them orbits a star called HIP 65426 and is located 385 light-years from Earth. However, this exoplanet lives very far from its parent star (much further than the outer planet of the solar system Neptune It lives from the Sun), which is also quite massive, about 12 times the size of the largest planet in the solar system Jupiter.
The latest observations of AU Mic’s debris disk promise that even much smaller planets could be imaged by Webb in the future.
So far, Webb hasn’t been able to take a direct image of an exoplanet orbiting AU Mic, however previous search (Opens in a new tab) In a press conference, Lawson revealed “many fast-moving clumps” in the debris disk that may have been caused by a hitherto unknown object.
While analysis of the disk was still in progress, Lawson told reporters that the disk had a final blue colour. This result is consistent with previous studies and indicates that the disk is made of tiny dust grains, which makes it brighter at shorter wavelengths.
Webb, who can Infrared wavelength detection From 0.6 to 5 μm, they clicked these images at 3.56 and 4.44 μm. This is “the first time the disc has been detected at these wavelengths,” Lawson told reporters at the press conference.
AU Mic is cosmically close at less than 32 light years and relatively young, about 23 million years old. It is also one of the rare systems in which a debris disc or “birth ring“–remnants of planetary formation still actively regenerated by the constant collisions of small bodies–almost on edge when viewed from Earth.
This provides astronomers with a great place to look for planets, since most of them have tilted orbits and will appear at some point in their revolutions around AU Mic.
Lawson said Webb’s capabilities and the study’s goal to focus on faint red dwarfs “allowed access not only to new types of exoplanets but to exoplanets that are very similar to the outer planets of our solar system.”
The AU Mic’s observations were part of a broader campaign focused on nine nearby red dwarf stars. The team shared the results on Wednesday (January 11) at the annual conference of the American Astronomical Society.
Follow Sharmila Kothonour on Twitter @Sharmilakg. Follow us on Twitter @tweet and on Facebook.