The infamous Apophis space rock has just lost its dangerous status – for the next 100 years at least – after new observations of the near-Earth asteroid.
Astronomers have been watching Apophis since its discovery in 2004, after initial estimates based on a more preliminary orbit suggested it would get uncomfortably close to our planet by 2029. 340 meters) wide – about 10 times bigger than the object created Meteor Crater in Arizona.
After refining the initial observations, astronomers found that there was no real risk of impact in 2029. Now, after Apophis safely passed Earth earlier this month, there’s more good news: The asteroid won’t hit Earth in 2068 either. The space rock has also been removed from a risk list known as the Sentry Impact Risk Table, that is operated by NASA’s Center for Near-Earth Object Studies (CNEOS), which is operated by the agency’s Jet Propulsion Laboratory.
Related: Huge asteroid Apophis unveiled in photos
The Sentry Impact Risk Table is a series of asteroids that graze asteroids so close to Earth that a future impact cannot be ruled out. This “risk list” tracks asteroids that are predicted to get close enough to Earth where there is a potential for collision, although fortunately there are no known immediate threats to our planet.
“When I started working with asteroids after college, Apophis was the poster child for dangerous asteroids,” Davide Farnocchia, who analyzes asteroid orbits at CNEOS, said in a statement
“It gives a sense of satisfaction to see it removed from the risk list, and we look forward to the science we will learn during the [next] close approach in 2029, “Farnocchia added. In 2029, Apophis will zoom past Earth at about 20,000 miles (32,000 kilometers) from our planet’s surface, slightly closer than geosynchronous satellites orbiting Earth.
This new information came from Apophis’ observations flyby of Earth on March 5, when the rock shot to within 0.11 astronomical units, with 1 AU representing the distance between the Earth and the sun (93 million miles or 150 million kilometers) from Earth. Observing this flyby, astronomers used radar to further refine our understanding of Apophis’ path around the sun.
The radar telescope at the Arecibo Observatory in Puerto Rico sadly retired a few months ago after it collapsed in 2020, but observations were still possible with facilities such as the Deep Space Network’s Goldstone complex in California and the Green Bank Telescope in West Virginia. The various telescopes showed good news for an asteroid that has been considered a risk for half a generation.
“An impact in 2068 is no longer possible, and our calculations show no impact risk for the next 100 years,” said Farnocchia. This allowed the group to remove Apophis from the risk list
Goldstone and Green Bank worked together to obtain imaging from Apophis, with Goldstone transmitting a radar signal and Green Bank receiving the reflection. The resulting radar images were grainy, but still showed a resolution of about 38.75 meters (127 feet) per pixel.
“If we had binoculars as powerful as this radar, we could sit in Los Angeles and read a dinner menu at a New York restaurant,” JPL scientist Marina Brozovic, who led the radar campaign, said in the same statement.
These new images will increase our understanding of asteroids. With the help of these observations, the teams studying the asteroid also hope to find out its shape; previous observations suggested that Apophis could be in the shape of a peanut.
They also want to learn more about the asteroid’s rotational speed and its axis spin, which will help predict what orientation the asteroid will have with Earth when it passes by in 2029. earthquakes “hit the rock’s surface, the team said.
The CNEOS information is sent to NASA Coordination Office for Planetary Defense, which works with telescopes and institutional partners in the United States and worldwide to get the latest information on the threats small bodies can pose to Earth.
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