My1sttoday: A mysterious asteroid almost hit earth but NASA didn’t see it until a day later.
A giant asteroid almost hit earth on September 16, but because it came from the direction of the sun, scientists didn’t see it coming.
If you heard a whooshing noise recently, you weren’t imagining it—there was indeed a gigantic asteroid that almost hit earth this month. And NASA didn’t see it coming.
The asteroid, named 2021 SG, has a diameter of around 42 to 94 m, with a diameter or around 68 m, which makes it around half the size of the great pyramids.
The asteroid tracker EarthSky has it listed for September 16, but NASA only detected it a day later.
Yeah, we almost got hit by an asteroid that we didn’t even notice. How? It’s because it was coming from the direction of the sun, a blind-spot for scientists.
Almost all asteroids that are detected by NASA and others come from the other direction of the solar system, coming towards the earth and the sun. This is known as coming from the “front”.
Rarely do asteroids come from the “back” but it does happen, but because they’re coming from the direction of the sun and head outwards in the solar system, they are very difficult to see, due to the sun’s bright rays blocking our view.
Quite literally, the sun was in our eyes.
The asteroid got super close to us, according to EarthSky. It was around half the distance between the earth and the moon—that’s how close. It passed Greenland and Canada at just past midnight GST on the 17th, an extremely close call.
This has happened before, and will happen again. One came from the sun that was smaller on September 7 that was only around 3.5m, just 15 thousand km from the earth.
“One of the reasons why it is hard to achieve the goal of finding 100% of all Near-Earth objects (NEO)… is because some have orbits that help ‘hide’ them from Earth-based observers,” said University of Hawaii astronomer Dave Tholen.
With all of the fancy tools that scientists have to detect asteroids, NASA currently has no way of detecting asteroids that are close to the sun. However, there is a new telescope called the Near-Earth Object Surveyor space telescope that is being launched in 2026 that will try to better detect these objects.
