As 2021 is nearing its end, the passing year marked the launch of NASA’s Double Asteroid Redirection Test (DART), a mission in the direction of building a planetary defence from asteroids. The launched spacecraft is expected to crash into Dimorphous, a moon of the double-asteroid Didyomos in September 2022, to change its path. Although the asteroid the spacecraft will crash into is non-threatening, the concern to protect our planet from asteroids is not out of thin air. Evidently, about 1,500 near-Earth asteroids flew past Earth this year. Here are five asteroids that nearly missed hitting our planet and flew by the closest distance of all.
This was relatively a very small space rock, just about 2.5 metres in diameter, that missed Antarctica by 3,000 kilometres, which is the closest an asteroid has come to the Earth in 2021. The interesting thing about 2021 AU1 is that because it was coming from towards the Sun, scientists missed it completely and came to know about four hours later than its closest approach, CNET reported.
About the size of a bus (around eight metres), the asteroid 2021 SP flew past Earth on September 17 at a distance of about 15,000 kilometres. If the asteroid had travelled 5,000 kilometres closer, it would have officially made it into our planet’s atmosphere. The space rock was travelling at a speed of 14 kilometres per second when it skimmed past our planet.
About five metres in diameter, 2021 RS2 zoomed past Earth at a distance of about 22,000 kilometres on September 8 this year. When the asteroid was flying at its closest distance to our planet, it was moving at a speed of 17 kilometres per second.
Roughly a little less than four metres in diameter, 2021 CZ3 travelled past Earth in February this year. The asteroid reached its closest to Earth at a distance of about 22,000 kilometres. The space rock was speeding at a speed of 11 kilometres per second when it nearly missed touching our planet.
About the size of a bus, the asteroid approached the Earth with a speed of about eight kilometres per second and flew past our planet at a distance of 26,000 kilometres.
None of the listed five asteroids was considered potentially hazardous by NASA because all of them were smaller than 150 metres in diameter, even though they could have proved to be dangerous. There were several potentially hazardous asteroids as well, which the space agency monitored until they passed.