Using NASA’s James Webb Space Telescope, astronomers have captured the first direct image of a planet outside of our solar system. Because the exoplanet is a gas giant and lacks a rocky surface, it is inhospitable to life.
The image, as seen through four different light filters, demonstrates how James Webb Space Telescope’s strong infrared vision can readily capture worlds outside of our solar system, paving the way for upcoming observations that will provide more data about exoplanets than has ever been available.
Sasha Hinkley, associate professor of physics and astronomy at the University of Exeter in the United Kingdom, who oversaw these observations with a sizable multinational cooperation, described them as a “transformative event,” not just for Webb but for astronomy in general. James Webb Space Telescope is an international mission that is run by NASA in partnership with the Canadian Space Agency and the European Space Agency.
The HIP 65426 b exoplanet in James Webb Space Telescope’s image has a mass that ranges from six to twelve times that of Jupiter, and these observations may assist in further refining that range. In comparison to our 4.5-billion-year-old Earth, it is a young planet, about 15 to 20 million years old.
Short infrared light waves were used to capture photographs of the planet that were taken in 2017 by astronomers using the SPHERE instrument on the Very Large Telescope of the European Southern Observatory in Chile. Because Earth’s atmosphere gives off its own infrared glow, ground-based telescopes can’t see more details, which Webb’s view at longer infrared wavelengths shows.
The information gathered from these observations has been analyzed by researchers, who are currently writing a report that will be submitted to journals for peer review. On the other hand, Webb’s first capture of an exoplanet already hints at future chances to study planets far away.
HIP 65426 b is sufficiently far away from its host star for James Webb Space Telescope to be able to distinguish the planet from the star in the image since it is 100 times further away from its host star than Earth is from the Sun.
Since its near-infrared camera (NIRCam) and mid-infrared instrument (MIRI) are both fitted with coronagraphs, which are little masks that block out starlight, James Webb Space Telescope can directly observe some exoplanets like this one. NASA will launch the Nancy Grace Roman Space Telescope at the end of this decade. It will have a coronagraph that is even more advanced.
Hinkley said that it was “very amazing” how well the Webb coronagraphs blocked the light from the host star.
Because stars are so much brighter than planets, it is difficult to take direct photographs of exoplanets. In the mid-infrared and near-infrared spectrums, the planet HIP 65426 b is a few thousand times fainter than its host star.
The planet appears as a slightly different shaped blob of light in each filter image. This is because of how Webb’s optical system changes light through its different lenses.
Aarynn Carter, a postdoctoral researcher at the University of California, Santa Cruz, who oversaw the photos’ analysis, said getting this image “was like mining for cosmic gold.” With careful image processing, I was able to exclude the star’s light and reveal the planet. At first, all I could see was light from the star, the author writes.
The HIP 65426b illustrates the way forward for Webb’s exoplanet exploration even though this is not the first direct image of an exoplanet to be taken from space—the Hubble Space Telescope has already taken direct planetary photographs.
The fact that we’ve only just begun, in my opinion, is what’s most exciting, added Carter. “There will be a ton more photos of exoplanets that will influence how we see their physics, chemistry, and formation in general. We might even find planets that weren’t known to exist. “
