# Will the stones on the moon fall on the earth?

Yes! It’s almost inevitable. Where’s the evidence? No hurry, let’s start with two facts. Fact 1 The moon has a mass of 0.0123 Earth, and gravity is only one-sixth that of earth, so the escape speed on the moon is only 2.38km/s, and if the speed reaches 1.32km/s, it can become a satellite orbiting the moon.

The 120 mm KEW-A1 armor-piercing projectile has an initial speed of 1740 m/s.

This means that some of the Earth’s kinetic energy armor-piercing projectiles, with their initial muzzle speeds of up to 1.74 km/s, could make the projectile a moon’s satellite by firing such a armor-piercing projectile on the moon.

Fact two

Meteoroids near Earth’s orbit can reach a maximum speed of 42 kilometers per second, while the Earth’s average rotation speed is 29.8 kilometers per second, which means that if the meteoroid sits not catching up with The Earth, but colliding head-on with the Earth, it can reach a speed of 71.9 kilometers per second before entering the atmosphere.

On Earth, because of the dense atmosphere, meteorites can not reach such high speed before landing, but unlike the moon, the vacuum on the moon has reached a very high vacuum, which means that the meteoroids that hit the moon can reach speeds of more than 70 kilometers per second.

Imagine that when a meteoroid hits the moon at a speed of about 70 kilometers per second, the rocks around the impact crater are bound to be blown away, and the strike rock speed is easy to reach the moon’s escape speed, or 2.38km/s.

Thus, the rocks escaped from the moon, some went straight to Earth, some continued to roam in orbit for tens of thousands of years, even hundreds of thousands of years, and finally captured by the Earth’s gravity.

That’s the fundamental reason why the rocks on the moon will fall on Earth.

Part.1

The first confirmed lunar meteorite.

The first time humans took stones directly from the moon was on July 24, 1969, when Apollo 11 returned to Earth and brought back 22 kilograms of lunar stones.

So, before that, even if someone did find a lunar meteorite, he could only be treated as an ordinary meteorite, because he could not confirm the origin of the meteorite.

The Antarctic Meteorite Search Program, or ANSMET, is a joint lying Antarctic meteorite search program sponsored by NASA and the National Science Foundation.

AnSMET explorers found a meteorite in Antarctica and were preparing to recycle it, pictured from H. Raab.

ANSMET explorers search for meteorites in Antarctica, pictured from NASA.

On January 17, 1982, members of the Antarctic meteorite search program discovered a meteorite near Mount Allen in Antarctica, which was then sent to the Houston Space Center for processing and storage, and because the center is responsible for the processing and storage of lunar samples, researchers are familiar with the lunar samples. When they were dealing with the meteorite from the South Pole, they found that its structural features were very similar to those of the lunar sample, and finally determined that it was a meteorite from the moon, named Mount Arun A81005.

Moon meteorite “A81005” of Mount Allen, weighing 31.4 grams.

Part.2

Moon meteorite s

The A81005 in Arundel is only the first confirmed lunar meteorite, but it is not the first to be found.

On November 20, 1979, the Japanese Antarctic Expedition discovered a meteorite codenamed “Yamato 791197” in The Antarctic, but due to its lack of experience at the time, the meteorite was mistaken for a common meteorite. It wasn’t until later, when it was compared to the moon rock that the Apollo moon landings were planned to retrieve, that it became known that it was a lunar meteorite.

Pictured is the Yamato 791197 meteorite, weighing 52.4 grams and being made of oblique rock horn sloping.

Part.3

\$40,000 per gram

Moon meteorites on Earth are scarce and the process of discovery is very slow. According to statistics, only one of the 1,000 meteorites found came from the moon, with the vast majority coming from the asteroid belt. By 1993, 12 lunar meteorites had been discovered worldwide, mainly from the South Pole, and only one moon meteorite, codenamed “Calcalong Creek”, was from Australia.

According to a paper published in the academic journal Polar Research, there were only 31 moon meteorites as of 2000.

Originally, people’s interest in moon meteorites was not so great. But then, the Calcalong Creek meteorite found in Australia was on the market for \$40,000 per gram, which is much more expensive than diamonds. Thus, this inspired folk meteorite enthusiasts to search for lunar meteorites, which made the moon meteorites to find a great increase in the speed.

By 2013, 165 lunar meteorites, with a total weight of 65.2 kg, had been announced.

As of July 2017, the number of moon meteorites announced to be discovered had risen to 353, with a total weight of 206.31 kg, equivalent to 54% of the weight of the rock brought back directly from the moon throughout the Apollo program, and 381.7 kg of lunar rock specimens were brought back by the Apollo missions.

As the number increases, the price of lunar meteorites is no longer that high, with the current market being \$600 to \$4,000 per gram. Abroad, people can buy from websites, but it’s risky, he says he’s selling moon meteorites, but is it really? And to find the authority to identify is an extremely cumbersome thing.

In 1978, when U.S. President Jimmy Carter’s security adviser, Brzezinski, visited China, he sent a sample of a lunar rock to china. The sample was then sent to Guiyang, so ouyang from far-far organization personnel to study, and Ouyang from far from the domestic nearly a hundred researchers, they divided the 1 gram of the moon rock into two halves, 0.5 grams preserved, 0.5 grams for research. Later, Chinese scholars published 14 related research articles on the 0.5-gram moon rock and concluded that the sample was collected by Apollo 17.

That said, if you pick up a meteorite that you think is a lunar meteorite, then at home, you have to go to the scholars who have studied the lunar samples before, and they are the ones who have seen and studied the moon’s rocks.