Giant Meteorite Struck Earth

Once upon a time—over 3 billion years ago—a giant meteorite that was 4 times bigger than today’s Mount Everest struck Earth. This meteorite was 200 times larger than the one that wiped out the dinosaurs. But when it struck, it may have given ancient microscopic life forms a boost.

This impact happened when Earth was very different than the planet we know today. At that time, life on Earth consisted only of simple bacteria and similar single-celled organisms.

It is postulated that back then, shorelines were shelves of shallow water, which would have been a low-energy environment without strong currents. After the impact, giant tsunamis would have swept the planet, ripping up the sea floor. The ocean’s surface boiled and so much dust was thrown up that it blocked out the sun.

Life, however, proved resilient. Ancient rocks from South Africa show that bacteria not only survived, it thrived in the aftermath. The impact stirred up iron from the ocean depths and delivered phosphorus (both from the meteorite and by increased erosion on land). This meant that certain bacteria that feed on these elements could flourish.

The site in South Africa where this evidence was found indicates there were at least 8 different major meteorite impacts from Earth’s early history.

 

https://www.msn.com/en-us/weather/topstories/giant-meteorite-4-times-bigger-than-mount-everest-struck-earth-and-sparked-life/ar-AA1sMZLq?ocid=hpmsn&cvid=18b6b70382694c0db33db3d6e10d311e&ei=82

Earth’s Temporary Moon

Earth has acquired a temporary moon. It has been tagging along with us for about 60 years and will continue to tag along until 2083. It is a small asteroid going by the name 2025 PN7.

Officially discovered by the University of Hawaii and confirmed this past week, it is what’s known as a “quasi-moon”—a rare celestial companion that travels almost exactly in sync with Earth. It’s not a true moon because it doesn’t orbit around the Earth. Right now, it is orbiting the sun, keeping pace with us so that it appears to shadow our planet.

2025 PN7 is estimated to be 18 to 36 meters wide, about the height of a small building, which is tiny by cosmic standards. That may be why it took so long to notice it.

Our real moon is held tight by gravity, but this asteroid isn’t bound to us. Think of it as a friendly jogger matching our stride on the same track—close enough to notice but never touching.

After 2083—if its current orbit holds that long—it will drift away into open space. At its closest approach to us, it gets within 4 million kilometers, which is roughly ten times the distance between Earth and the moon. At its most distant, it can swing out to 17 million kilometers. That changing distance is because of the competing gravity of the sun and various planets.

So far, astronomers have confirmed only eight quasi-moons. Each of them is a small but valuable clue in understanding how asteroids move and how Earth’s gravity shapes the space around us. These objects are more than curiosities. They help refine orbital models, improve predictions for near-Earth asteroids, and could serve as testing grounds for future missions. After all, they’re close, relatively stable, and reachable without traveling too far from home.

2025 PN7 will never outshine our real moon. But it’s there and worth knowing about.

 

https://www.msn.com/en-us/news/technology/nasa-confirms-earth-now-has-two-moons-until-2083/ar-AA1OQpRt?ocid=hpmsn&cvid=68f6da61133a4c1f869a4eb40f801f5c&ei=63