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Samples 15556, 60015, and 70017 at the Lyndon B. Johnson Space Center in Houston.
The first person to set foot on the moon had one last task to complete before returning home.
Neil Armstrong had to choose rocks – as much as he could carry, as interesting as possible. The collected material would constitute the first samples of humanity taken from another world.
Less than 10 minutes from the end of his walk on the moon, Armstrong used forceps to put about 20 stones in a specialized collection box. Judging that it was not full enough, he added 13 extra pounds of lunar earth in the container.
Today, a tablespoon of this earth sits in a sealed dish in a closed, windowless laboratory at the Johnson Space Center in Houston. It is a valuable part of Apollo's greatest scientific legacy: nearly 300 kg of lunar rocks.
For 50 years, research on these rocks has transformed our understanding of the moon, revealing the circumstances of its birth and the reasons for its birth. marbled face. NASA has decided to publish three new samples for badysis, samples that no scientist has touched.
Future experiments, on vacuum-sealed cores and long-frozen rock, can only be performed once, with the samples open. That's why the materials have been withheld since they were recovered from the moon, said Ryan Zeigler, head of the Apollo Rock Collection. NASA was waiting for the right scientists, with the right technologies, at the right time.
This year, on the occasion of the 50th anniversary of Apollo 11, the renewed interest in the Moon before a return mission project, said Mr. Zeigler.
NASA's Lunar Sample Laboratory, a labyrinth of sparkling metal cabinets and unblemished linoleum floors, was built in the 1970s to house the reported rocks of six lunar missions.
A sophisticated HVAC system, designed to maintain air 1000 times. cleaner than in the outside world, fills the installation with a slight artificial breeze. Scientists only intervene after wearing special white coveralls, caps and booties to limit contamination.
These are some of the most valuable rocks in the solar system, said Zeigler. Just look at what they've revealed up until now.
Before the Apollo 11 mission, scientists could not agree on where the moon came from. It's an unsuitable in the solar system – much bigger compared to its planet than almost any other moon. Some have badumed that it was once an independent object "captured" by Earth's gravity. Others have suggested that the satellite forms in orbit along the Earth when the planets merge from a primordial dust disk. Many textbooks have taught that it was actually a ball of earth that had been projected by the effects of our planet. It was thought that the Pacific Ocean was a scar from this ancient loss.
All these theories had to be abandoned as soon as scientists would have seen the first rocks of Apollo.
The materials of the moon were extraordinarily ancient – 4.5 billion years ago. years. Although they contain many of the same chemicals as the rocks of the Earth, they are surprisingly poor in "volatile" – molecules such as water and carbon dioxide that vaporize readily when they are heated. Some contained features produced only in cataclysms – meteor showers, volcano explosions, or sunspot dams.
At a conference to discuss early discoveries six months after the return of Apollo 11 to Earth, no one could agree on what all these evidence meant.
Then, toward the end of the lecture, geologist John Wood explained how the clues intertwined. He realized that the strange white spots present in the soil sample hastily collected by Armstrong belonged to an unusual type of rock called anorthosite, which forms when the mineral feldspar crystallizes in the rock. in fusion.
A large sample of i8 lunar rocks contained in tight tanks at the Lyndon B. Johnson Space Center in Houston, Texas on March 19, 2019.
The hypothesis was also confirmed by data from seismometers deployed by comrade Armstrong, Buzz Aldrin, and his successors on subsequent Apollo missions revealed that the Moon had relatively little iron in its center. After the collision, the theory remains, heavy elements such as iron sank into the Earth's core while lighter elements were swept into what became the moon. (The Earth is the densest planet in the solar system.)
Other rocks have helped us "see beyond the moon" in the history of the world. whole solar system that, Zeigler says. Most of Earth's geological records have been altered by water and wind or engulfed by plate tectonics, but the surface of the moon still bears the scars of all the volcanoes that have exploded and all the meteors that have They are never crushed. The lunar samples provided evidence of an era called late intensive bombardment, when the inner planets were attacked by an asteroid dam, about the time life came to life on Earth. And by counting the craters on areas of the moon whose ages are known from Apollo samples, scientists have put together a system to estimate the age of the entities located on them. Other planets.
The study of the moon's material closely has not fully explained its history. . On the one hand, the researchers can not find any molecular fingerprint of Theia – the object whose collision with the Earth would have created the moon. Scientists also can not agree on how the water traces found themselves in the samples, while the global ocean magma should have boiled everything up.
"The story is certainly not complete," Zeigler said.
NASA hopes that the three newly available samples – which represent half of all the lunar material that the space agency has in store – will help answer these questions.
Some researchers will look for traces of water in a rock that has been stored in a freezer for nearly 50 years. Others will look for volatile molecules, including water, trapped in tiny glbad beads formed from lunar lava fountains that exploded billions of years ago.
Several teams will work together to examine the materials contained in empty vacuum tubes sealed by astronauts during their stay. were still on the moon. The way rocks are stratified can provide information on landslides that shape the lunar landscape in the absence of wind, weather and life. Captured gases indicate how the material has been altered by radiation, which will help scientists understand how long the rock has been exposed to light before the astronauts can box it and take it away.
Some measurements, such as the badysis of captured gas images, can only be done when the tanks are open. Scientists will spend months repeating the experiment on specimens containing samples from the Antarctic before the big event.
"It's exciting to open something new," said Barbara Cohen, a planetary scientist at NASA's Goddard Space Flight Center, who will drive the gas. badysis. "We do not know what we are going to find."
At the annual lunar and planetary science conference meeting in Houston this spring – the 50th event since the one when the Apollo 11 samples were first shown several years ago – ads
The United States has not taken any new moon material since Apollo's last landing in 1972, and no lunar rocks have been brought to Earth from the Soviet Luna 24 spacecraft. stole four years after that. China has planned a sample return mission this year and President Donald Trump has ordered NASA to send astronauts back to the moon by 2024. But a 2011 law bans US federal scientists from collaborating with the Chinese Space Agency and a lack of funding for NASA has generated skepticism about Trump's moonlighting.
To fully answer the outstanding questions, "we need a better overall representation of lunar rock types," Cohen said. And for that, "we have to go back."
But meanwhile, she said, the decision to open the Apollo samples is like a "mini-mission" in itself; one more chance to probe a piece from another place; one more chapter in the history of the moon.
(With the exception of the title, this story has not been altered by NDTV staff and is published from a syndicated feed.)
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