Astronomers utilize the exceptional sensitivity of the Mid-infrared instrument (Miri) on the NASA/ESA/CSA James Webb Space Telescope to investigate exoplanets within the three-ring debris disks surrounding the 6.4 million-year-old star TWA 7.
This Webb/Miri image shows the exoplanet TWA 7b, comparable in mass to Saturn. Image credits: NASA/ESA/CSA/WEBB/AM LAGRANGE/M. ZAMANI, ESA & WEBB.
Debris disks, comprised of dust and rocky materials, can exist around both young and evolved stars, but they are more luminous and detectable around younger celestial bodies.
These disks are often identified by their visible rings and gaps, which are believed to be shaped by planets that form within them.
The star TWA 7 is a low-mass (0.46 solar mass) M-type star situated approximately 111 light-years away in the constellation of Antlia.
Also referred to as Ce Antilae or Tyc 7190-2111-1, it is part of the TW Hydra Association.
The nearly edge-on three-ring fragmented disks make TWA 7 an optimal target for Webb’s highly sensitive mid-infrared observations.
“Our observations indicate a strong candidate for the planet that influences the structure of the TWA 7 debris disk, located precisely where we anticipated finding a planet of this mass,” states Dr. En Marie Lagrange, an astronomer at the Observatoire de Paris-PSL.
On June 21, 2024, Dr. Lagrange and colleagues employed a coronagraph with Webb’s Miri instrument to effectively suppress the bright glare of the host star, uncovering faint nearby objects.
This method, known as high contrast imaging, enables astronomers to directly observe planets that would otherwise be obscured by the overwhelming light of their host stars.
After eliminating residual starlight through advanced image processing, a faint infrared source was detected near TWA 7, distinguishable from background galaxies or other solar system objects.
This source is located within one of the three dust rings previously identified around TWA 7 by earlier ground-based investigations.
Its brightness, color, distance from the star, and position within the ring align with theoretical expectations for a young, cold Saturn-mass planet that shapes the surrounding debris disks.
“They are also the most popular and highly skilled professionals,” remarked Dr. Matilde Marin, an astronomer at Johns Hopkins University and the Institute for Space Telescope Science.
The team’s preliminary analysis suggests that the object known as TWA 7B has a mass approximately 0.3 times that of Jupiter (about 100 times that of Earth) and may be a young, cold exoplanet with a temperature of 320 K (around 47°C).
Its positioning (approximately 52 AU from the star) corresponds with a gap in the disk, indicating a dynamic interaction between the planet and its surroundings.
Once corroborated, this discovery marks the first direct link between a planet and the structure of debris, offering initial observational insights into the Trojan disk.
“These findings underscore Webb’s capability to probe previously unobservable low-mass planets orbiting nearby stars,” the astronomer commented.
“Ongoing and future observations will seek to more accurately characterize candidates, investigate the state of their atmospheres, and enhance our understanding of planet formation in young systems and the evolution of disks.”
“This preliminary result represents an exciting new frontier where Webb sheds light on the discovery and characterization of exoplanets.”
These findings are detailed in a publication in the journal Nature.
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Lagrange et al. Evidence of sub-Jovian planets within the young TWA 7 disk. Nature Published online on June 25th, 2025. doi:10.1038/s41586-025-09150-4
Source: www.sci.news
