Astronomers discover new potentially catastrophic asteroid
NASA had recently concluded with an exciting experiment that crashing a rocket into an asteroid can alter its trajectory thus saving Earth from a catastrophic collision, and the Earth may need that concept tested again sooner rather than later as an international team of astronomers announced the discovery of a large asteroid whose orbit crosses that of Earth, creating a small chance far in the future of a catastrophic collision.
"2022 AP7 crosses Earth's orbit, which makes it a potentially hazardous asteroid, but it currently does not now or anytime in the future have a trajectory that will have it collide with the Earth," said lead author of the findings, astronomer Scott Sheppard of the Carnegie Institution for Science.
The potential threat comes from the fact that like any orbiting object, its trajectory will be slowly modified due to myriad gravitational forces, notably by planets. Forecasts are therefore difficult on the very long term.
The newly discovered asteroid is "the largest object that is potentially hazardous to Earth to be discovered in the last eight years," said NOIRLab, a United States-funded research group that operates multiple observatories.
The risk is therefore very small, but in case of a collision, an asteroid of that size "would have a devastating impact on life as we know it," said Sheppard. He explained that dust launched into the air would have a major cooling effect, provoking an "extinction event like hasn't been seen on Earth in millions of years."
Some 30,000 asteroids of all sizes – including more than 850 larger than a kilometer wide – have been cataloged in the vicinity of the Earth, earning them the label "Near Earth Objects" (NEOs). None of them threaten Earth for the next 100 years.
In preparation for a future discovery of a more threatening object, NASA conducted a test mission in late September in which it collided a spacecraft with an asteroid, proving that it was possible to change its trajectory.