Thanks for subscribing! Access your favorite topics in a personalized stream while on the go. download the app
NASA’s James Webb Space Telescope is revealing new galaxies that astronomers have never seen before, deep in the early universe. Astronomers recently pointed JWST at an object called MACS0647-JD. They are extremely far away and light takes time to travel, so looking at such a distant object is also a look back in time. MACS0647-JD is about 97% of the way back to the Big Bang, within the first 400 million years of the universe. Dan Coe, a researcher at the Space Telescope Science Institute, first discovered it 10 years ago with the Hubble Space Telescope, which was previously NASA’s most powerful space observatory. “With Hubble, it was just this pale, red dot. We could tell it was very small, just a tiny galaxy in the first 400 million years of the universe. Now we’re looking with Webb and we’re able to resolve TWO objects,” he said Coe in a NASA announcement in October. JWST is 100 times more powerful than Hubble, and its infrared lens allows it to peer much further into the deep universe and the distant past. By comparing the new JWST image with previous Hubble images, astronomers discovered new features of one of the oldest galaxies ever seen. Hubble and JWST images of MACS0647-JD. SCIENCE: NASA, ESA, CSA, STScI and Tiger Hsiao (Johns Hopkins University) IMAGE EDITED: Alyssa Pagan (STScI) Both Hubble and JWST study the early universe through gravitational lensing. This happens when a distant galaxy cluster is so massive that it distorts space-time, bending light from galaxies far behind it. This creates mirror images of these galaxies, reflected back to us. So the footprint of the mysterious MACS0647-JD system appears in three places in the images above. The bursts of these three images of the JD system, at right, show how much clearer the JWST images are. They clearly show two different objects. One of the lensed images of MACS0647-JD, from the James Webb Space Telescope. SCIENCE: NASA, ESA, CSA, Dan Coe (STScI), Rebecca Larson (UT), Yu-Yang Hsiao (JHU) IMAGE EDITED: Alyssa Pagan (STScI) “We’re actively debating whether it’s two galaxies or two star clusters within a galaxy. We don’t know, but those are the questions Webb is designed to help us answer,” Coe said. The research is not yet published, but the difference between the images is stark.

JWST could reveal galaxy mergers and other unseen actions in the early universe

                            A pair of interacting galaxies, imaged in near-infrared light by Webb, and ultraviolet and visible light by Hubble.  NASA, ESA, CSA, Rogier Windhorst (ASU), William Keel (University of Alabama), Stuart Wyithe (University of Melbourne), JWST PEARLS Team, Alyssa Pagan (STScI)

One of the objects is bluer, indicating that relatively young stars are forming within it. The other is redder, indicating an older object with more interstellar dust. “We may be witnessing a galaxy merger in the very early universe. If this is the most distant merger, I’ll be really ecstatic,” Tiger Yu-Yang Hsiao, a Ph.D. who studied the images with Coe, said in the NASA announcement . . Two galaxies colliding and merging, as photographed by the Hubble Space Telescope. NASA, ESA, STScI, Julianne Dalcanton (Center for Computational Astrophysics / Flatiron Inst. and University of Washington). Joseph DePasquale (STScI) JWST will likely reveal even more distant galaxies from the beginning of the universe. This will help scientists piece together the missing history of the first 400 million years. “Until this point, we haven’t really been able to study galaxies in the early universe in great detail. We only had dozens of them before Webb. Studying them can help us understand how they evolved into galaxies like ours Live to today. And also how the universe has evolved over time,” Rebecca Larson, another doctoral student who studied the images, said in the NASA statement. It highlighted all the other tiny dots in the new JWST image — each one a distant galaxy. The JWST image of the MACS0647-JD system, triple-lensed by a massive galaxy cluster in front of it. SCIENCE: NASA, ESA, CSA, Dan Coe (STScI), Rebecca Larson (UT), Yu-Yang Hsiao (JHU) IMAGE EDITED: Alyssa Pagan (STScI) “It’s amazing the amount of information we’re getting that we couldn’t see before,” he said, adding, “And this is not a deep field. This is not a long exposure. We haven’t even really tried to use this telescope to look in one spot for a long time. This is just the beginning!”