Latest news with #Near-InfraRedCamera
Yahoo
28-03-2025
- Science
- Yahoo
James Webb telescope zooms in on bizarre 'Einstein ring' caused by bending of the universe
When you buy through links on our articles, Future and its syndication partners may earn a commission. The James Webb Space Telescope (JWST) has captured a stunning image of a bizarre astronomical optical illusion. This "rare cosmic phenomenon", called an Einstein ring, appears as a single eye-like orb in the darkness of space, but is actually a distorted view of two distant galaxies in the constellation Hydrus. In the bright center of this cosmic spectacle is one galaxy, while the stretched orange and blue color surrounding it is the light from another galaxy located behind it. The light from the more distant galaxy looks like a ring because it has been distorted by gravitational lensing. Gravitational lensing occurs when the gravity of a massive object — like a galaxy or a black hole — bends the light from a more distant object. This effect is a direct consequence of Einstein's theory of relativity, which states that mass warps the fabric of space-time, causing light to follow curved paths, like a ball rolling down a curved slope. "This effect is much too subtle to be observed on a local level, but it sometimes becomes clearly observable when dealing with curvatures of light on enormous, astronomical scales," ESA representatives wrote in a statement. This latest image was released by ESA and the Canadian Space Agency today (March 27) as their March picture of the month. It was captured by JWST's Near-InfraRed Camera instrument and also includes data from the Wide Field Camera 3 and the Advanced Camera for Surveys instruments on the Hubble Space Telescope. Related: 42 jaw-dropping James Webb Space Telescope images Einstein rings like these are created when the distant light source, the massive lensing object, and the observer are perfectly aligned, resulting in the light appearing as a complete ring wrapped around the lensing object. As a result, they are rare. In this case, the elliptical galaxy in the foreground — which is part of a galaxy cluster named SMACSJ0028.2-7537 — is so massive that it is bending the light of the spiral galaxy situated far behind it. "Even though its image has been warped as its light travelled around the galaxy in its path, individual star clusters and gas structures are clearly visible," according to the statement The fascinating phenomenon of gravitational lensing also allows astronomers to better understand the universe. RELATED STORIES —James Webb telescope captures auroras on Neptune for first time ever —James Webb telescope reveals 'cosmic tornado' in best detail ever — and finds part of it is not what it seems —'Unlike any objects we know': Scientists get their best-ever view of 'space tornadoes' howling at the Milky Way's center Light emitted from distant galaxies, which existed long ago in the past, is often too faint to be observed directly from Earth. Strong gravitational lensing magnifies these galaxies, making them appear larger and brighter, and allowing astronomers to study some of the first galaxies formed after the Big Bang. "Objects like these are the ideal laboratory in which to research galaxies too faint and distant to otherwise see," the ESA statement noted. Additionally, because black holes and dark matter don't emit light, scientists can use gravitational lensing to detect and study these phenomena by measuring how they bend and magnify background stars.
Yahoo
20-02-2025
- Science
- Yahoo
Webb Catches Mysterious Light Flares Around Milky Way's Supermassive Black Hole
Between spotting galaxies that shouldn't exist, capturing the interstellar medium with unprecedented clarity, and identifying new worlds, the James Webb Space Telescope is a busy observatory. But as it orbits the Sun, Webb has kept a close eye on one of the most obscure pieces of our galaxy: Sagittarius A*, the supermassive black hole at the center of the Milky Way. By capturing the longest and most detailed Sag A* observations yet, Webb has allowed astronomers to catch a constant light show around the black hole's accretion disk, which draws in Sag A*'s cosmic meals. In a study published Tuesday in The Astrophysical Journal Letters, an international team of researchers from several space science organizations shared that Webb's NIRCam (Near-InfraRed Camera) spotted many pops of light near Sag A* across 48 hours of observation. These flashes, which varied in strength, appeared to flare from the inner edge of the black hole's accretion disk. Flares aren't unusual near supermassive black holes, so on its own, the identification of light flares around Sag A* wouldn't have been particularly exciting. What was odd about the team's findings was that Sag A*'s light show never appeared to stop, even as the team studied the flashes over seven 8-to-10-hour observation periods between 2023 and 2024. The only variables they noticed were in wavelength and length of time—data that, thanks to NIRCam's dual modules, could be captured simultaneously during a single session. "Flares are expected to happen in essentially all supermassive black holes, but our black hole is unique," said astrophysicist and lead study author Farhad Yusef-Zadeh in a Northwestern University statement. "It is always bubbling with activity and never seems to reach a steady state. We observed the black hole multiple times…and we noticed changes in every observation. We saw something different each time, which is really remarkable. Nothing ever stayed the same." Yusef-Zadeh and his colleagues believe the flares could be the product of the same phenomenon that produces sporadic flashes near other black holes: feisty accretion disks. These swirling disks of gas and dust gravitationally pull matter toward the black hole, eventually tipping that material past the point of no return (the black hole's event horizon). This steady stream of snacks allows the black hole to grow in mass. Every now and then, turbulence within the accretion disk squeezes the disk's plasma, triggering a quick burst of radiation. "It's similar to how the Sun's magnetic field gathers, compresses, and then erupts a solar flare," Yusef-Zadeh told NASA. "Of course, the processes are more dramatic because the environment around a black hole is much more energetic and much more extreme. But the Sun's surface also bubbles with activity." But an even more powerful force could be behind Sag A*'s larger flares. When two magnetic fields collide in space, they release energy in the form of accelerated particles. These particles travel so fast that they emit bright bursts of radiation, according to NASA. If "magnetic reconnection events" are happening in Sag A*'s accretion disk, that could explain the more aggressive pops of light. In the future, the researchers hope to use Webb's NIRCam to observe Sag A* for 24 hours straight. Only a long, uninterrupted period like this would allow the team to see whether the accretion disk's light show is based on any particular pattern or is truly random.
