Exoplanets are planets that orbit suns other than our own, which helps us understand if we are unique in the universe or if there are other planets similar to Earth. In this case, it is HIP 65426 and it has the honor of being the first exoplanet officially captured by the James Webb Space Telescope, which was launched into space in December 2021 to unravel the mysteries of the origins of the universe.
While this isn’t the first direct image of an exoplanet taken from space (the Hubble Space Telescope has captured direct images of exoplanets before), HIP 65426 b points the way forward for James Webb’s exoplanet exploration.
HIP 65426 is a very young exoplanet . It is barely 15-20 million years old (remember that the Earth is 4.5 billion years old). The telescope used its Near Infrared Camera (NIRCam) and Mid Infrared Instrument (MIRI) which can block out the light from surrounding stars to take these fantastic snapshots.
all in infrared
Webb’s images are made through four different light filters. They show a gas giant, a planet just outside our solar system but without a rocky surface; it could not be habitable. Despite this, these images open the way to future observations that can reveal a wide range of information about exoplanets that we did not know until now.
This alien world was first discovered in 2017 by the SPHERE instrument on the European Southern Observatory’s Very Large Telescope (VLT) in Chile, but long wavelengths were blocked by Earth’s atmosphere. Now we have a much more accurate view, because the image they have presented is taken in mid-infrared light. It reveals much more detail than the ground-based telescopes on the VLT campus. This is due to the intrinsic infrared glow of the Earth’s atmosphere. Webb’s technology is able to capture the longer infrared wavelengths without interruption as the telescope rises through space.
The scientists are currently analyzing these scientific images and will submit their study for peer review in hopes of future publication. But everything indicates that we will have more and better possibilities to study worlds far away from us.
“But James Webb’s first capture of an exoplanet already hints at future possibilities for studying distant worlds ,” NASA explained in a statement.
A star or a planet?
One of the researchers’ most pressing concerns was making sure there was a star associated with the large gas giant, proving that it was, in fact, an exoplanet and not a dwarf star. Images from the Webb Telescope show that HIP 65426 b is close enough to a star to be in its orbit , and about 100 times farther from that star than Earth is from our own star.
“I think the most exciting thing is that we’ve only just begun,” said Aarynn Carter. “There are many more images of exoplanets to come that will shape our general understanding of their physics, chemistry, and formation. We may even discover previously unknown planets.
Future studies will likely investigate how HIP 65426 b formed and evolved over time. Meanwhile, other astronomers plan to use Webb to study many other exoplanets , especially large ones that are relatively far from their host star and thus can be directly imaged.
Reference: Carter, AL et al. Preprint at https://arXiv.org/abs/2208.14990 (2022).
Chauvin, G. et al. Astron. & Astrophys. 605, L9 (2017)
NASA/ESA/CSA, A. Carter (UCSC), the ERS 1386 team, and A. Pagan (STScI)
