Earth has been knocked about quite a bit by asteroid strikes during its long history. All of the planets in our solar system have been heavily bombarded at one time or another, just look at the Moon. Asteroid strikes still occur, just not as often or as dramatically in the past.
Nearly 170 terrestrial impact craters have been identified on Earth ranging from a few meters to 300km (186 miles) in diameter.
Check the video created by MBS that puts the size of some of these craters into perspective! Have a Blast!
If you check websites like spaceweather.com or NASA’s CENEOS (Center for Near Earth Object Studies) and view the list of projected asteroid close approaches, you won’t find the little bugger that just snuck past us.
That’s because 2021 GW4 was discovered just days before it nearly smacked into Earth! As I have said repeatedly, “It’s not the asteroids we know about, it’s the ones we haven’t found yet that scare me!”
From Yahoo! News:
There will be no “Armageddon” type of situation on Earth, this time, after an asteroid the size of car just missed hitting Earth on Monday April 12th.
The asteroid, known as 2021 GW4, traveled at 18,700 miles per hour when it passed the planet. At its closest, the asteroid was just over 12,000 miles away from Earth’s surface at 9:01 a.m. ET. For reference, most geostationary satellites are around 22,000 miles awa,y and the moon is roughly 238,900 miles away.
The asteroid was first discovered on April 8 at the Catalina Sky Survey in Mt. Lemmon, Arizona.
Astronomer and founder of the Virtual Telescope Project Gianluca Masi said it was “an exceptionally close encounter.” He captured an image of the asteroid when it was over 186,000 miles from Earth and can be seen in the middle of the image with an arrow pointed at it.
“We repeat this is an absolutely safe close approach. Asteroids of that size coming so close are relatively rare, but so far this year we had four objects coming within 0.07 lunar distance from Earth’s center: 2021 GW4 is the largest of these four rocks,” Masi said.
NASA estimated that the asteroid was between 3.5-7.7 meters long, and tracked how close its orbit came to Earth’s. The size is the reason why people were not able to see it without a telescope.
It’s common for space rocks similar to 2021 GW4 to hit Earth as it happens about once a year, according to NASA. However space rocks smaller than 25 meters, over three times the size of 2021 GW4, often burn up and create, “an impressive fireball” as they enter Earth’s atmosphere.
NASA estimates that it would take an asteroid more than half a mile long to cause worldwide effects after impact.