![]() “They’re not today's Milky Way,” she notes. We're really not seeing the earliest stages of galaxy formation yet.”Īt the same time, she notes that yesterday’s disks are different than modern ones. “I think the surprise is to see so many of them. “We're not surprised to see disk galaxies,” Kartaltepe clarifies. Since disks are thought to form only in serene environments, in which stars can settle into a spinning skirt instead of being thrown about, their prevalence in a universe only a few percent of its current age is a bit like seeing teens when expecting toddlers. Though not part of the current study, these barred galaxies are demonstrative of the mature galaxy shapes already present at early times. A montage of JWST images shows barred galaxies dating back to between 8.4 billion and 11 billion years ago. The percentage of disk galaxies declined only slightly in the early universe, while the fraction of those with a central bulge and those with an irregular shape stayed roughly constant over cosmological time. But in the meantime, the job is still very much human: Three CEERS team members examined each of the 850 galaxies to make the classifications.ĭespite their youth, the galaxies had shapes similar to those nearer to us. In the future, such classifications will probably be left to computers Kartaltepe’s student, Caitlin Rose (also at RIT) is already working on convolutional neural networks and other computational methods that will eventually take over. Some galaxies, for example, have both a disk and a central bulge, much like the Milky Way. “Galaxies are complex, and they don’t necessarily fall into just one box,” Kartaltepe says. Those classifications were not mutually exclusive. The CEERS group has used the new data (both images and spectra) to find 850 early galaxies, measure the distance to each one, and then tag its shape as “disk,” “spheroid,” or “irregular.” Webb’s images are also sharper than Hubble’s, and its sensitivity greater. The longer wavelengths Webb detects enable it to see farther back in time. That’s where the Webb telescope comes in. Then again, those previous studies also had a hard time classifying the most distant ones, which looked like little more than smudges. Previous studies, such as those done using the Hubble Space Telescope, had suggested that as we look back toward a younger universe, the stable rotating disks of today give way to more chaotic shapes, representative of the violent mergers that built up the first galaxies. Speaking as part of the Cosmic Evolution Early Release Science (CEERS) collaboration, Jeyhan Kartaltepe (Rochester Institute of Technology) reported Webb’s views of galaxies when the universe was between 500 million years and 2 billion years old. Levay Cutout images: NASA / STScI / CEERS / TACC / S. This is one of the first images obtained by the Cosmic Evolution Early Release Science Survey (CEERS) collaboration and contains several examples of high-redshift galaxies with various morphologies, including a surprisingly high fraction of disks. ![]() Young But Mature This image - a mosaic of 690 individual frames taken with Webb's Near Infrared Camera (NIRCam) - covers a patch of sky near the handle of the Big Dipper. The results may end up changing what we know about how the first galaxies formed. In the first batch of images from Webb, the spectrum is reversed so that it more easily shows where the greatest amount of light has been blocked.Evidence is building that the first galaxies formed earlier than expected, astronomers announced at the 241st meeting of the American Astronomical Society in Seattle, Washington.Īs the James Webb Space Telescope views swaths of sky spotted with distant galaxies, multiple teams have found that the earliest stellar metropolises are more mature and more numerous than expected. This creates dark absorption lines in the spectrum, a kind of molecular fingerprint describing the atmosphere's chemical composition. As the star's light is filtered through the planet's atmosphere, molecules within the atmosphere absorb specific wavelengths of starlight, effectively blocking those wavelengths from reaching us. The transmission spectrum reveals molecules in the planet's atmosphere as it transits, or moves in front of its star from our perspective. ("WASP" stands for "Wide Angle Search for Planets," which has used arrays of robotic cameras in the Canary Islands and South Africa to discover almost 200 exoplanets so far.) ![]() WASP-96b is a " hot Jupiter" exoplanet, a gas giant that orbits extremely close to its star. As part of the first set of science data from the James Webb Space Telescope, NASA released the transmission spectrum for WASP-96b, an exoplanet located 1,150 light-years away.
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