The famous Apophis space rock is just shedding its dangerous status – for at least the next 100 years – after a new look at the asteroid near Earth.
Astronomers have been monitoring Apophis since its discovery in 2004, after initial orbit-based predictions more predictably said it would come to an awkward close to our planet in 2029. The large size of Apophis added to this concern, as it stretches 1,100 feet (340 meters) across – about 10 times larger than that of created Meteor Crater in Arizona.
After refining the first observations, astronomers discovered that there was no real threat of impact in 2029. Now, after Apophis safely passed through Earth earlier this month, there is more good news: no the asteroid hit the Earth in 2068 either. The space rock has been removed from a hazard list called the Sentry Impact Risk Register, which maintained by NASA’s Center for Near-Earth Object Studies (CNEOS), which is managed by the organization’s Jet Propulsion Laboratory.
Related: Large asteroid apophis shown in pictures
The Sentry Impact Risk Register is a set of asteroids that show asteroids grazing so close to Earth that future impacts cannot be ruled out. This “danger list” monitors asteroids that are expected to get close enough to Earth to where there is potential for impact, although we are happy, there are no known nearby threats to the planet. us.
“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.
“There is some satisfaction in seeing it removed from the risk list, and we look forward to the science we can find during [next] close contact in 2029, “added Farnocchia. In 2029, Apophis will move with the Earth at about 20,000 miles (32,000 kilometers) from the surface of our planet, slightly closer than geosynchronous orbiting satellites.
This new information came from comments on Apophis’ Earth flyby on March 5th, when the rock awoke within 0.11 celestial units, with 1 AU representing the distance between the Earth and the sun (93 million miles or 150 million kilometers), of the Earth. By looking at this flyby, astronauts used radar to further improve our understanding of the Apophis orbit around the sun.
Unfortunately the radar telescope at the Arecibo Observatory Puerto Rico retired a few months ago after its collapse in 2020, but it was still observable with facilities such as the Goldstone Deep Space Network building in California and the Green Bank Telescope there. West Virginia. The various telescopes showed good news for an asteroid that is considered a threat for half a generation.
“The impact of 2068 is no longer in the capacity scenario, and our calculations do not show any impact risk for at least the next 100 years,” Farnocchia said. This allowed the group to remove Apophis from the risk list
Goldstone and Green Bank worked together to get images of Apophis, with Goldstone sending out a radar signal and Green Bank receiving the reflection. The resulting radar images were pixelated, but still showed a resolution of about 38.75 meters (127 feet) per pixel.
“If we had binoculars as powerful as this radar, we would be able to sit in Los Angeles and read a dinner menu at a restaurant in New York,” said JPL scientist Marina Brozovic, who led the radar campaign, in the same statement.
This new image grows our understanding of asteroids. Also, using these observations, the teams studying the asteroid hope to find a shape; previous observations suggested that Apophis could be shaped like a nut.
They also want to know about the rotation rate of the asteroid and its spinning axis, which will help predict which side the asteroid is on Earth when it flies by in 2029. the close connection to our planet could alter the asteroid spinning state or cause “asteroid vibrations” on the rock surface, the team said.
CNEOS information is provided to NASA Planning Protection Coordination Office, which works with telescopes and institutional partners in the United States and around the world to keep up – to – date on the potential dangers of small groups to Earth.
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