It's heading our way as well - sort of
Astronomers have discovered three near-Earth asteroids, one of which would be classed as a 'planet killer'.The planet killer in question has been named 2022 AP7 and is between 1.1km and 2.3km in diameter. This makes it the largest PHA discovered since 2014 and probably in the top 5% of the largest ever found.
Writing in the Astronomical Journal, lead study author Scott Sheppard and colleagues at the Carnegie Institution for Science in Washington say that 2022 AP7 crosses the Earth’s orbit, making it a potentially hazardous asteroid, known as a PHA.
The three asteroids had previously been hidden within the Sun's glare but were able to be detected in a brief moment of twilight.
Sheppard said in a statement: “Our twilight survey is scouring the area within the orbits of Earth and Venus for asteroids.”
“So far we have found two large near-earth asteroids that are about 1 kilometre across, a size that we call planet killers.”
Explaining why 2022 AP7 was so dangerous, Sheppard said: “Any asteroid over 1km in size is considered a planet killer.
“The Earth’s surface would likely cool significantly from sunlight not getting to the planet. It would be a mass extinction event like hasn’t been seen on Earth in millions of years."
Don't panic just yet though. At present, the asteroid only crosses our orbit when the Earth is on the other side of the Sun.
Over time, it will start to cross Earth's orbit, but Sheppard explained this will not be until "centuries into the future and we do not know the orbit of 2022 AP7 precise enough to say much about its dangers centuries from now.”
Hopefully,
NASA's preparations for what to do about a planet-threatening asteroid will prove to be effective if - or when - the time comes.
