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Newsweek
09-05-2025
- Science
- Newsweek
'Space Jaws': NASA Reveals Roaming Monster Black Hole That's Eating Stars
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. Just when you thought it was safe to go back in the cosmos, NASA's Hubble Space Telescope has discovered a terrifying, roving, oft-invisible monster dubbed "Space Jaws." Lurking 600 million light-years away, the supermassive black hole—which has the same mass as some 1 million suns—betrayed its presence when it was caught shredding and then devouring a poor star that got too close. Dubbed AT2024tvd, the burst of radiation from this "tidal disruption event" (TDE) was also picked up by NASA's Chandra X-Ray Observatory, the National Radio Astronomy Observatory's Very Large Array in New Mexico and Caltech's Palomar Observatory. Together, the observations revealed that this TDE is unique among the 100-odd detected to date—as it doesn't appear to come from the core of the black hole's host galaxy. An artist's impression of a supermassive black hole devouring a star. An artist's impression of a supermassive black hole devouring a star. NASA, ESA, STScI, Ralf Crawford STScI "Theorists have predicted that a population of massive black holes located away from the centers of galaxies must exist, but now we can use TDEs to find them," said paper author and astronomer professor Ryan Chornock of the University of California, Berkeley explained in a statement. "AT2024tvd is the first offset TVD captured by optical sky surveys and it open up the entire possibility of uncovering this elusive population of wandering black holes with future sky surveys," added paper lead and UC Berkeley astrophysicist Yuhan Yao. Yao added: "Right now, theorists haven't given much attention to offset TDEs. I think this discovery will motivate scientists to look for more examples of this type of event." The galaxy (orange) and the tidal disruption event (blue) as imaged by the Hubble Space Telescope and the Chandra X-Ray Observatory. The galaxy (orange) and the tidal disruption event (blue) as imaged by the Hubble Space Telescope and the Chandra X-Ray Observatory. NASA, ESA, STScI, Yuhan Yao UC Berkeley); Joseph DePasquale (STScI In AT2024tvd's host galaxy, there is a second, larger black hole in the galactic core—one weighing some 100 million times the mass of the sun. Despite being in the same galaxy, the two supermassive holes are not bound together as a gravitational pair. At present, the two black holes are separated by only around 2,600 light-years (roughly one-tenth of the distance between Earth and Sagittarius A*, the Milky Way's central black hole), with the smaller hole moving around the host galaxy's bulge. In the future, the smaller black hole may spiral into its larger peer, resulting in the two merging together. As to how the smaller black hole got so far off-center—it is possible that there were originally three black holes in the galaxy's core, and the other two kicked the runt out of the litter. This, Yao says, would explain the roaming black hole's current positioning. She explained: "If the black hole went through a triple interaction with two other black holes in the galaxy's core, it can still remain bound to the galaxy, orbiting around the central region." Alternatively, it is possible that the smaller black hole was once at the center of another, smaller galaxy that collided with the host galaxy at least a billion years ago. Paper co-author and astronomer Erica Hammerstein, also of UC Berkeley, did not find any evidence of a past galaxy merger in Hubble's images of the galaxy. However, she said: "There is already good evidence that galaxy mergers enhance TDE rates, but the presence of a second black hole in AT2024tvd's host galaxy means that at some point in this galaxy's past, a merger must have happened." The full findings of the study will be published in The Astrophysical Journal Letters. Do you have a tip on a science story that Newsweek should be covering? Do you have a question about black holes? Let us know via science@
Express Tribune
12-04-2025
- Science
- Express Tribune
Webb telescope reveals alien planet died in fiery plunge toward its star
An artist's concept shows a ring of hot gas left after a star consumed a planet, in this undated illustration. NASA's James Webb Space Telescope observed such a ring and also found an expanding cloud of cooler dust enveloping the scene. PHOTO: NASA, ESA, CSA, Ralf Crawford (STScI)/Handout via REUTERS Listen to article In May 2020, astronomers for the first time observed a planet getting swallowed by its host star. Based on the data at the time, they believed the planet met its doom as the star puffed up late in its lifespan, becoming what is called a red giant. New observations by the James Webb Space Telescope - sort of a postmortem examination - indicate that the planet's demise happened differently than initially thought. Instead of the star coming to the planet, it appears the planet came to the star, with disastrous consequences - a death plunge after an erosion of this alien world's orbit over time, researchers said. The end was quite dramatic, as evidenced by the aftermath documented by Webb. The orbiting telescope, which was launched in 2021 and became operational in 2022, observed hot gas likely forming a ring around the star following the event and an expanding cloud of cooler dust enveloping the scene. "We do know that there is a good amount of material from the star that gets expelled as the planet goes through its death plunge. The after-the-fact evidence is this dusty leftover material that was ejected from the host star," said astronomer Ryan Lau of the US. National Science Foundation's NOIRLab, lead author of the study published in the Astrophysical Journal The star is located in our Milky Way galaxy about 12,000 light-years from Earth in the direction of the constellation Aquila. A light year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). The star is slightly redder and less luminous than our sun and about 70% of its mass. The planet is believed to have been from a class called "hot Jupiters" - gas giants at high temperatures owing to a tight orbit around their host star. "We believe it probably had to be a giant planet, at least a few times the mass of Jupiter, to cause as dramatic of a disturbance to the star as what we are seeing," said study co-author Morgan MacLeod, a postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics. Jupiter is our solar system's largest planet. The researchers believe that the planet's orbit had gradually deteriorated due to its gravitational interaction with the star, and hypothesized about what happened next. "Then it starts grazing through the atmosphere of the star. At that point, the headwind of smashing through the stellar atmosphere takes over and the planet falls increasingly rapidly into the star," MacLeod said. "The planet both falls inward and gets stripped of its gaseous outer layers as it plows deeper into the star. Along the way, that smashing heats up and expels stellar gas, which gives rise to the light we see and the gas, dust and molecules that now surround the star," MacLeod said. But they cannot be certain of the actual fatal events. "In this case, we saw how the plunge of the planet affected the star, but we don't truly know for certain what happened to the planet. In astronomy there are lots of things way too big and way too 'out there' to do experiments on. We can't go to the lab and smash a star and planet together - that would be diabolical. But we can try to reconstruct what happened in computer models," MacLeod said. None of our solar system's planets are close enough to the sun for their orbits to decay, as happened here. That does not mean that the sun will not eventually swallow any of them. About five billion years from now, the sun is expected to expand outward in its red giant phase and could well engulf the innermost planets Mercury and Venus, and maybe even Earth. During this phase, a star blows off its outer layers, leaving just a core behind - a stellar remnant called a white dwarf. Webb's new observations are giving clues about the planetary endgame. "Our observations hint that maybe planets are more likely to meet their final fates by slowly spiraling in towards their host star instead of the star turning into a red giant to swallow them up. Our solar system seems to be relatively stable though, so we only have to worry about the sun becoming a red giant and swallowing us up," Lau said.
