The James Webb Space Telescope JWST took photos of starsAnd the planetsAnd the galaxies – Now we can add exoplanets to the list. NASA reports that Webb has seen his first exoplanet, known as HIP 65426 b. This is not a new discovery, but it does show that the telescope is performing better than its designers had hoped.
HIP 65426 b orbits a star 385 light-years from Earth, which is nearby in the grand scheme. The planet, which is 6-12 times the mass of Jupiter, was discovered in 2017 by the SPHERE instrument on the European Space Agency’s Very Large Telescope. VLT has succeeded in capturing an image of the alien world, making it one of the few exoplanets to be imaged directly. A new JWST image reveals more details.
While astronomers have confirmed the existence of more than 5,000 exoplanets, most of them have been identified through gravitational or stellar transit observations. Imaging directly these worlds is challenging because the stars orbiting them are much brighter in size. In the case of HIP 65426 b, the star is 10,000 times brighter. It is only visible because it is massive and orbits at a much greater distance than the planets in our solar system. Neptune is located about 30 AU (30 times the distance between the Earth and the Sun) from the Sun, but HIP 65426 b is 87 AU from its star.
The image below shows HIP 65426 b at four different infrared wavelengths – from left to right: 3 µm, 4.44 µm, 11.4 µm, and 15.5 µm. The pill-shaped lights in the shorter wavelength images are not part of the HIP 65426 system. The star indicates the location of the host star HIP 65426. NASA says they are just artifacts of the telescope’s optics. Deformation aside, this is the first time an exoplanet has been imaged below 5 micrometers. Webb is designed to operate in infrared, which is why it is in the Earth-Sun L2 Lagrange Point. Ground-based observatories experience more infrared interference from Earth’s atmosphere.
“This is my transformationwrong, not only for Webb but also for astronomy in general,” Sasha Hinckley from the University of Exeter said:Who led the international team. While the data has not yet been peer reviewed, it appears that Webb was able to provide more accurate mass and luminance data on HIP 65426 b. This also confirms that the planet is inconsistent with our current models of planet formation. Future observations may be able to explain why, but this is just the beginning of Webb’s work on exoplanets.
Based on this early data, it appears that the telescope will exceed its expected performance by a factor of 10. It should be able to resolve a planet one-third the size of Jupiter at 100 AU from a Sun-like star. A planet like Neptune should be visible at 100-200 astronomical units of a red dwarf. In the nearby Alpha Centauri system, Webb should be able to see a planet with a radius five times the Earth’s radius between 0.5 and 2.5 AU. It’s been an uphill journey, but all the years of working at JWST are paying off.