Asteroid That Threatened Earth Shaped Like a Saucer, Scientists Find With Large Telescope
The preferred analogy has been to compare the shape to a hockey puck. To us, this sounds like a huge missed opportunity to say that the Earth was — however briefly — under threat by a literal flying saucer, just like in that one movie.
The findings come from a preprint study, accepted for publication in The Astrophysical Journal Letters. Using the Gemini South Observatory in Chile, the astronomers imaged the roughly 200-foot asteroid, 2024 YR4, in multiple wavelengths, revealing that it was rapidly rotating once every 20 minutes, in addition to its unusual UFO-like appearance.
"This find was rather unexpected since most asteroids are thought to be shaped like potatoes or toy tops rather than flat disks," lead author Bryce Bolin from Eureka Scientific said in a statement about the work.
The chunky space rock was first spotted in late December of last year. Soon, early observations predicted that there was a small but disquieting chance of one percent that it could hit our planet. By February, the odds surpassed 3 percent, before the space rock was finally determined determined to be on a harmless trajectory.
At the time, from what scientists could tell from visible light observations, 2024 YR4 appeared to be around 300 feet long, a size large enough to wipe out a metropolis should it strike one. Recent research using the James Webb Space Telescope's infrared capabilities, however, determined it was actually no more than 220 feet long, or about the size of a 10-story building, and as small as 174 feet. This latest study backs up that estimate, independently concluding that YR4 is between 98 to 213 feet in diameter.
Digging deeper, the astronomers studied the asteroid's lightcurves, finding that 2024 YR4 is what's known as an S-type asteroid rich in silicates. That's not surprising, but its origins are: the asteroid appears to have been nudged our way by Jupiter out of the solar system's main asteroid belt, a ring of rocky objects surrounding the Sun that stretches between the orbits of Mars and the gas giant — specifically, a region called the central main belt.
Previously, astronomers suspected 2024 YR4 came from the inner main belt, based on its composition — but its retrograde spin revealed in these latest observations indicate otherwise.
"We are a bit surprised about its origin in the central main asteroid belt, which is a location in the asteroid belt that we did not think many Earth-crossing asteroids could originate from," Bolin said.
While it no longer poses a threat to Earth, there's still a 3.8 percent chance YR4 could veer into the Moon, according to the latest Webb observations. If it does, the impact will leave a nasty scar — but shouldn't alter the lunar world's orbit.
More on space: Scientists Intrigued by Stars Singing Ancient Songs
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Newsweek
12 hours ago
- Newsweek
Ancient Burial Discovery Might Redefine Our Past
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. Archaeologists have uncovered what may be one of the world's oldest human burial sites, dating back around 100,000 years. The remains of five early humans—two complete skeletons and three skulls—were found deliberately arranged in burial pits deep inside Tinshemet Cave in central Israel. Researchers said the site provides rare and compelling evidence of organized funerary behavior during the Middle Paleolithic period, offering new insight into the early origins of ritual, custom, and possibly belief. Why It Matters The discovery significantly extends the timeline for intentional human burial, a behavior long viewed as a marker of symbolic thinking and social complexity. The careful positioning of bodies, combined with the presence of pigments and objects that served no practical function, suggests that early Homo sapiens may have developed ritual customs earlier than previously confirmed. Professor of Archaeology Yossi Zaidner works in Tinshemet Cave, where archaeologists are excavating one of the world's oldest known burial sites, dating back 100,000 years, near Shoam, Israel, on July 15, 2025. Professor of Archaeology Yossi Zaidner works in Tinshemet Cave, where archaeologists are excavating one of the world's oldest known burial sites, dating back 100,000 years, near Shoam, Israel, on July 15, 2025. Ariel Schalit/AP Photo What to Know Tinshemet Cave, excavated over the past decade, has revealed the remains of at least five individuals—Homo sapiens and Neanderthal-like hominins—each carefully laid to rest in shallow pits, curled in fetal positions and surrounded by hundreds of ceremonial objects. The consistent placement of the bodies suggests intentional burial, according to Yossi Zaidner, one of the site's excavation directors and a professor of archaeology at Hebrew University in Jerusalem. Early Discoveries Some of the most significant discoveries from Tinshemet Cave were published in March in Nature Human Behavior. Researchers identified the remains as early humans: two full skeletons and three isolated skulls, along with additional bones and teeth. They also documented over 500 fragments of red and orange ocher, each produced by heating iron-rich stones—a process thought to reflect early humans' capacity for symbolic or decorative creation. "Here we see a really complex set of behaviors, not related to just food and surviving," Zaidner told The Associated Press. Volunteers work in Tinshemet Cave near Shoam, Israel, on July 15, 2025. Volunteers work in Tinshemet Cave near Shoam, Israel, on July 15, 2025. Ariel Schalit/AP Photo Excavation 'Nails Down' Dates Tinshemet Cave is exceptionally important to archaeologists because the local climate preserved the bones, tools, and ornaments in good condition—unlike many other parts of the world where such items have been lost to time. Christian Tryon, a professor at the University of Connecticut and a research associate at the Human Origins Program at the Smithsonian Institution who was not involved in the study, said, "There were so many uncertainties with those sites, but this is confirming it's a pattern we know, and they're really nailing down the dates." Archaeologists said it will take many more years to fully excavate the site. Using hand chisels and pen-sized pneumatic drills resembling dental tools, researchers are proceeding with extreme care to protect the fragile finds. A volunteer scrapes away around remains in Tinshemet Cave near Shoam, Israel, on July 15, 2025. A volunteer scrapes away around remains in Tinshemet Cave near Shoam, Israel, on July 15, 2025. Ariel Schalit/AP Photo What People Are Saying Yossi Zaidner, an archaeologist and excavation co-director: "The skeletons were located in pits and arranged in a fetal position, recognized as a burial position." Christian Tryon, a professor at the University of Connecticut: "There were so many uncertainties with those sites, but this is confirming it's a pattern we know, and they're really nailing down the dates." What Happens Next With much of Tinshemet Cave still unexcavated, archaeologists expect many more years of fieldwork. As new discoveries emerge, researchers hope to deepen their understanding of how and when early humans began treating death with ritual, symbolism, and meaning.
Yahoo
a day ago
- Yahoo
‘City Killer' Asteroid Won't Hit Earth, But What Happens If It Slams Into The Moon?
Earth has dodged a celestial bullet, but the moon might not be so lucky, and that has scientists keeping their telescopes and minds trained on a massive asteroid called '2024 YR4.' That's not its official name, but more on that later. When it was first discovered, this asteroid had a very small chance of impacting Earth in December of 2032, but later observations concluded the space rock no longer poses any significant risk to our planet. Since then, additional data has helped experts refine the asteroid's potential trajectory and they say the probability of it striking the moon in 2032 has now risen to 4.3%. That's still a very small chance, but there could be some complications for our planet if that collision happens. (MORE: Lego Man's Epic Space Journey) Back To The Beginning 2024 YR4 first caught astronomers' attention in December 2024. It made headlines when its probability of impacting Earth got as high as 3%. It's so far away that it appears as just a tiny glimmer, but using infrared images captured by NASA's James Webb Space Telescope, scientists estimate that it's the size of a 10-story building, about 200 feet in diameter. It's considered a near-Earth asteroid, meaning it's in an orbit that brings it within Earth's region of the solar system. Its size earned the asteroid the nickname 'city killer' since it could cause severe damage to a city or region if it struck Earth. 2024 YR4 is the temporary name given to the rock. While those who discovered it will get to suggest an official name, it could be months or years before that official name is decided by the International Astronomical Union. What Happens If It Strikes The Moon? If this asteroid hits the moon, scientists say it will make impact at a speed of tens of thousands of miles per hour. That would create a huge crater, but more importantly, it could also send fragments of moon rock and granular lunar material flying off the moon. While it's unlikely the Earth would face any significant danger from the lunar strike, that debris could put nearby astronauts at risk, as well as satellites that we depend on for GPS, cellphones, internet and weather forecasting. What about the International Space Station? Well that would be at risk, except that NASA plans to decommission and deorbit the ISS in 2031, a year before the asteroid's potential impact. (MORE: New Images Show Universe Like Never Before) Would We Be Able To See The Collision? The latest calculations from June suggest it's likely the asteroid could hit the near side of the moon, the side pointing towards us. So we could be able to see the once-in-a-lifetime collision here on Earth. Dr. Paul Wiegert, a physics and astronomy professor at Western University told Western News, 'If YR4 hits the moon, it will be the largest asteroid to have hit the moon in about 5,000 years. It's quite a rare event.' Wiegert says, 'People at home will be able to see the explosion with small telescopes or even binoculars.' He also says that if moon rock is launched into space, 'We should also get to see quite a spectacular meteor shower,' within a week of the collision. So What Now? Asteroid 2024 YR4 is currently too far away to detect with space or ground-based telescopes, as it orbits around the sun. But out of sight, does not mean out of mind – NASA expects to make more observations and collect new data when the asteroid's orbit brings it back into Earth's vicinity in 2028. Solve the daily Crossword
New York Post
a day ago
- New York Post
Massive asteroid on potential impact path with the Moon could trigger destructive meteor shower on earth
What happens if an asteroid the size of a 15-story building crashes into the Moon in 2032? While the chances of the newly discovered asteroid 2024 YR4 hitting the Moon in seven years are slim – there is currently a 96% chance it won't happen – an impact of this size would not come without consequences for the Moon, astronauts and spacecraft orbiting Earth. A new study submitted for review by scientists with the University of Western Ontario and Athabasca University in Canada took observations from the James Webb Space Telescope of asteroid 2024 YR4 and used simulations to show how much lunar debris would be ejected out into space, sending pieces of the Moon toward Earth. After its initial discovery late last year, the asteroid appeared to have a small chance of impacting Earth, warranting international attention, and jumping to the highest asteroid threat ever given on the Torino Impact Hazard Scale. By February, more ground-based observations of the asteroid helped clear the threat to Earth, but the Moon still faces a possible impact. 3 Any lunar debris that makes it within Earth's atmosphere could create a meteor shower event over the planet. NASA Earlier this year, NASA's James Webb Space Telescope helped scientists determine that the asteroid is between 175 and 220 feet in diameter. If Asteroid 2024 YR4 crashes into the Moon, it would create a crater more than half a mile in diameter (1 km), becoming the largest impact in about 5,000 years, according to the study. Current calculations show, if it happens, an impact would occur on the Southern Hemisphere. The researchers said this impact would threaten satellites in low-Earth orbit for days or up to a few months, and send a fraction of the ejecta toward Earth. 3 The current impact corridor for 2024 YR4 (yellow) projected on a map of the Moonâs near side from Lunar Reconnaissance Orbiter. Any lunar debris that makes it within Earth's atmosphere could create a meteor shower event over the planet. 'The resulting meteor shower could last a few days and be spectacular, though the number of visible meteors somewhat muted by the low entry speed of ejecta,' the research team said. With more than 10,000 active satellites in low-Earth orbit and more than 25,000 pieces of space junk, researchers believe an asteroid strike to the Moon could spell trouble for satellite operators. 3 On March 26, 2025, NASAâs James Webb Space Telescope captured images of asteroid 2024 YR4 that indicate the asteroid is about the size of a 15-story building. NASA 'Given the very large total exposed area for satellites by 2032, it becomes possible that hundreds to thousands of impacts from mm-sized debris ejected by a lunar impact from 2024 YR4 will be experienced across the entire satellite fleet,' the study authors wrote. 'Such impacts may damage satellites, but are small enough to generally not end active missions or cause breakups.' The researchers say material from the Moon could be a 'serious hazard to moon-orbiting spacecraft' such as NASA's Lunar Gateway, a planned orbiting station for astronauts, and an 'even greater danger' to any lunar surface operations. Asteroid 2024 YR4 has moved behind the Sun, limiting any new observations until 2028. Scientists say those new observations in a few years will help improve lunar impact predictions.
