Jupiter’s Twin? Webb Telescope Reveals Its Frozen Doppelganger Just 12 Light-Years Away

Epsilon Ende Ab is colder than any other planet ever imaged outside our solar system.

If alien astronomers in a nearby star system had a telescope like NASA‘s James Webb Space Telescopeand point them towards our solar system, then Jupiter It may look very similar to this new image taken by Webb. exoplanet Epsilon Ende Ab is one of the coldest exoplanets ever directly detected, with an estimated temperature of about 35 degrees. F (2 degrees CelsiusEpsilon Ende Ab is about 180 degrees Fahrenheit (100 degrees Celsius) hotter than the gas giants in our solar system. With many known exoplanets that are not like planets in our solar system, Epsilon Ende Ab offers a rare opportunity for astronomers to study the atmospheric composition of real analogues in the solar system.

This image of the gas giant exoplanet Epsilon Indi Ab was taken using the Mid-Infrared Imager (MIRI) instrument on NASA’s James Webb Space Telescope. The star symbol indicates the location of the host star Epsilon Indi A, whose light was blocked by the MIRI, resulting in the dark circle outlined by a dashed white line. Epsilon Indi Ab is one of the coldest exoplanets ever directly imaged. The blue color is mapped to light at 10.6 microns, while the orange color is mapped to light at 15.5 microns. The MIRI was unable to identify the planet, which is a point source. Credits: NASA, ESA, CSA, MPIA, Elizabeth Matthews

Webb Space Telescope images of a cool exoplanet 12 light-years away

An international team of astronomers using NASA’s James Webb Space Telescope has captured a direct image of an exoplanet about 12 light-years away from Earth. The planet, Epsilon Indi Ab, is one of the coldest exoplanets ever observed.

The planet is several times the mass of Jupiter and orbits the K-type star Epsilon Indi A (Eps Ind A), which is about the same age as our Sun but slightly cooler. The team observed Epsilon Indi Ab using the coronagraph on the Webb telescope. Mary (Mid-Infrared Instrument). Only a few dozen exoplanets have previously been directly imaged by space-based and ground-based observatories.

“Our previous observations of this system were indirect measurements of the star, which actually allowed us to see ahead of time that there was likely a giant planet in this system pulling on the star,” said team member Carolyn Morley of the University of Texas at Austin. “That’s why our team chose this system to observe first with Webb.”

“This discovery is exciting because the planet is very similar to Jupiter – it is slightly warmer and more massive, but more similar to Jupiter than any other planet imaged so far,” added Elizabeth Matthews, lead author of the study from the Max Planck Institute for Astronomy in Germany.

Since its launch in 2021, the James Webb Space Telescope has been exploring the earliest moments of the universe with its advanced infrared capabilities and large mirror. It provides detailed insights into galaxies, stars and exoplanets, dramatically enhancing our understanding of the cosmos. Credit: NASA

Solar system counterpart

Previously imaged exoplanets tend to be the youngest and hottest exoplanets, still radiating much of the energy they did when they first formed. As the planets cool and shrink over their lifetimes, they become much dimmer and therefore more difficult to image.

“Cool planets are very faint, and most of their emissions are in the mid-infrared range,” Matthews explained. “Webb is ideally suited to doing mid-infrared imaging, which is very difficult to do from Earth. We also needed good spatial resolution to separate the planet from the star in our images, and Webb’s large mirror is very helpful in this regard.”

Epsilon Indi AB is one of the coldest exoplanets ever directly detected, with an estimated temperature of about 35 degrees Fahrenheit (2 degrees Celsius)—colder than any other planet imaged outside our solar system, and colder than all but one of the free-floating brown dwarfs. The planet is only about 180 degrees Fahrenheit (100 degrees Celsius) warmer than the gas giant planets in our solar system. This provides a rare opportunity for astronomers to study the atmospheric composition of real solar system analogues.

“Astronomers have been imagining planets in this system for decades; fictional planets orbiting Epsilon Indy have been the setting for Star Trek episodes, novels, and video games like Halo,” Morley added. “It’s exciting to see a planet there ourselves, and to begin measuring its properties.”

Not quite what we expected

Epsilon Indi Ab is the twelfth closest exoplanet to Earth known so far and the closest planet larger than Jupiter. The science team chose to study Epsilon Ind A because the system showed hints of a possible planetary body using a technique called radial velocity, which measures the back-and-forth wobbles of the host star along our line of sight.

“While we expected to image a planet in this system, given the radial velocity cues, the planet we found is not what we expected,” Matthews shared. “It is about twice as massive, slightly farther from its star, and has a different orbit than we expected. The reason for this discrepancy is still an open question. The planet’s atmosphere also appears to be slightly different from what the model predicted. So far, we only have a few optical measurements of the atmosphere, which means it’s hard to draw conclusions, but the planet is fainter than expected at shorter wavelengths.”

The team believes this could mean that there are large amounts of methane, carbon monoxide and carbon dioxide in the planet’s atmosphere, which absorb shorter wavelengths of light. It could also indicate a very cloudy atmosphere.

Direct imaging of exoplanets is particularly valuable for characterizing them. Scientists can collect light directly from the observed planet and compare its brightness at different wavelengths. So far, the science team has only been able to detect Epsilon Indi b at a few wavelengths, but they hope to revisit the planet using Webb to conduct optical and spectroscopic observations in the future. They also hope to discover other similar planets using Webb to find possible trends in their atmospheres and how these objects formed.

Nancy Grace coming from NASA roman space telescope Scientists will use the Coronagraph to demonstrate direct imaging technology by photographing Jupiter-like worlds orbiting sun-like stars—something that has never been done before. These results will pave the way for future missions to study more Earth-like worlds.

These results were captured using Webb’s Cycle 1 General Observer 2243 and published in the journal nature.

To learn more about this discovery, see Giant Jupiter Discovered: The Oldest, Coldest Exoplanet Ever Imaged by the James Webb Telescope.

Reference: “A moderate super-Jupiter imaged with the James Webb Telescope in the mid-infrared” by E. C. Matthews, A. L. Carter, B. Pathak, C. V. Morley, M. W. Phillips, S. Krishanth PM, F. Feng, M. J. Ponce, L. A. Bogard, J. A. Burt, I. J. M. Crossfield, E. S. Douglas, T. Henning, J. Hom, C. L. Coe, M. Casper, A. M. Lagrange, D. Petit de la Roche, F. Philippot, 24 July 2024, nature.
doi: 10.1038/s41586-024-07837-8

The James Webb Space Telescope (JWST), launched on December 25, 2021, represents a huge leap forward in astronomical capabilities. As the successor to Hubble Space TelescopeThe James Webb Telescope is designed to observe the universe primarily in the infrared spectrum, allowing it to peer through cosmic dust and peer into the early moments of the universe. Its large, segmented primary mirror, spanning 6.5 metres, and its suite of advanced scientific instruments enable the telescope to capture extraordinarily detailed images of distant galaxies, star-forming nebulae and exoplanets, providing unprecedented insights into the origins of stars, planetary systems and the universe itself. The James Webb Telescope is a collaborative project of NASA, the US space agency NASA, and the University of Cambridge. European Space Agency (ESA), and the Canadian Space Agency (CSA), and is expected to radically change our understanding of the universe.