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Asteroid-exploring spacecraft passes over Earth
NASA’s Lucy spacecraft blasted through Earth’s atmosphere on Sunday, passing just 220 miles above the surface. The spacecraft is on a 12-year quest to explore eight asteroids. (October 18)
AP
Astronomers have spotted three near-Earth asteroids, two of which pose a potential threat as “planet killers” due to their large and dangerous size, but don’t worry, a NASA expert says, they’re not expected to harm us.
According to findings published in the Astronomical Journal on Monday, the three asteroids – which belong to a group found in the orbits of Earth and Venus – were previously undetectable through a telescope due to the glare and brightness of the sun.
But an international space team of astronomers waited until twilight at an observatory in Chile to examine the asteroids using a dark energy camera from the Víctor M. Blanco 4-meter telescope, according to the National Science Foundation’s NOIRLab.
The largest asteroid is the most dangerous object to pose a significant threat to Earth in the past eight years, researchers say. One of the asteroids, called 2022 AP7, is just under a mile across, but has an orbit that could reach Earth’s path in the distant future. However, the timing is uncertain, according to the journal’s findings.
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The other two asteroids, 2021 LJ4 and 2021 PH27, pose less of a collision risk with Earth, researchers say.
“Our twilight survey scans the region within the orbits of Earth and Venus for asteroids,” said study lead author Scott S. Sheppard, an astronomer at the Carnegie Institution for Science’s Earth & Planets Laboratory in Washington, DC. “So far we have found two large near-Earth asteroids that are about 1 kilometer in diameter, a size we call killer planets.”
Scientists from the study determined that the asteroid most likely to cross Earth’s orbit would “stay very far from Earth,” mainly because the sun would block it, since the time of crossing Earth’s orbit would be when Earth it is on the opposite side of the sun. .
If a half-mile-long asteroid ever connected with Earth, the results for the planet could be “disastrous,” according to Sheppard, because of the effects the pollutants would have on the atmosphere.
“It would be a mass extinction event the likes of which has not been seen on Earth for millions of years,” Shepard said.
Asteroid threat to hit Earth ‘not dangerous’ says NASA expert
Although the observed asteroids could have devastating effects on the plant, don’t assume it will collide with Earth, said Paul Chodas, director of NASA’s Jet Propulsion Laboratory Center for Near-Earth Object Studies, who was not involved in the study.
“We know this asteroid is not dangerous,” Chodas told USA TODAY. “It remains very far from Earth, kind of locked into a habitation that keeps it as actually one of the most distant of the asteroids that we categorize as potentially hazardous.”
The center tracks all space objects that cross or approach Earth’s orbit around the sun. There are more than 30,000 near-Earth asteroids that have been discovered, but 857 of them are just over half a mile across, according to NASA. According to the center’s database, asteroid 2022 AP7 is predicted to make close approaches to Mars and Jupiter only in the next 145 years.
Chodas said the asteroid’s ability to wreak havoc was taken away from the main focus of the research because it’s an excellent example of the search for asteroids that are too close to the sun to see, which should continue.
2021 PH27 is the closest known asteroid to the sun, NOIRLab announced.
He added that NASA plans to send a probe into space in 2026 to observe asteroids in the region, hoping to spot any that could pose a threat to Earth. By finding these asteroids, the agency could prepare plans similar to the DART mission, where a spacecraft crashed into an asteroid to alter its course.
“The most important thing in planetary defense is to find them and find them with plenty of warning time,” Chodas said.
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