[Naidheachdan New Tang Dynasty, 07 Samhain, 2024, àm Beijing]Every day, 48.5 tons ofmeteoritematerial effectEarthatmosphere almost allmeteoriteThey burn up when they come down, and the pieces that make it to the Earth’s surface are called meteorites. because of some of themspace rockGoing back to the early stages of our solar system and remaining unchanged since its formation, they can provide clues about the environment in which the sun and our planets formed.
However, until recently, scientists had only found 6% of more than 70,000 known meteorites.sourceand trace their origin to the moon, Mars or Vesta (one of the largest asteroids in the asteroid belt of the solar system).
Now, an international team of experts has determined the origin of more than 90 percent of known meteoritessourceand revealed that an astonishing 70% came from just three families of asteroids in the asteroid belt, which lies between the orbits of Mars and Jupiter. Their results were published in three papers in the journals Astronomy & Astrophysics and Nature in September and October respectively.
“For meteoritologists, finding the source of an asteroid meteorite sample is like finding a pot of gold at the end of a rainbow,” said Sara Russell, a planetary scientist at London’s Natural History Museum who was not involved. , to this Science News.new research.
3 asteroid families
The team studied theEarthShapes of meteorites found on Earth and telescopic studies of materials from the main asteroid families in the asteroid belt. According to the statement, they studied the formation of these asteroid families through simulation modeling.
An asteroid family is “a group of asteroids with similar orbits because they are pieces produced when two asteroids collide.” Two thingsnew researchLead author Miroslav Brož, an astronomer at Charles University in the Czech Republic, told Reuters.
The three major asteroid families identified in the study are Karin, Koronis and Massalia. They were formed in three collisions 5.8 million years ago, 7.5 million years ago, and about 40 million years ago. These are relatively young compared to the total age of our solar system, which is generally thought to be around 4.6 billion years.
“Recent collision events in the asteroid belt completely affect the flow of this material to our planet,” said Michaël Marsset, a researcher at the European Southern Observatory and lead author of one of the papers. new, to Gizmodo. “You might think that the meteorite stream would be a mixture of all the classes of writing that we see in the asteroid belt, but that’s not true. It is dominated by three asteroids that have recently broken up.”
This makes sense because young asteroid families contain more asteroid fragments because they formed recently. Collisions between these particles sometimes push the debris into Earth’s orbit. Over tens of millions of years, the impact of collisions will gradually reduce the number of particles in these clusters.
Especially “chondrites“
According to Reuters, researchers discovered that two families, the Karin and Koronis families, provide a type of meteorite called H chondrites, which make up 33 percent of Earth’s known meteorites. The Massalia family produces a type of meteorite called L chondrites, which make up 37% of Earth’s meteorites
Chondrite sample showing chondrules and metallic fragments. (H. Raab/CC By-SA 3.0)
In total, Chondrites make up 85% of the meteorites found on Earth. As Trevor Ireland, a researcher at the University of Queensland in Australia, said in his article on “The Conversation” website, these meteorites are meteorites of a rock type with special round grains (called chondrules) and to They often contain olives Stone and pyroxene, these silicate minerals are thought to be the building blocks of our solar system.
“Chondrites are primitive meteorites that have largely preserved their original composition since they formed in our protoplanetary disk,” Marsset told Reuters about the formation of planets.
In other words, chondrites are ideal meteorites for studying the origin of our solar system.
However, Russell is concerned that Earth’s meteorites represent such a limited sample of asteroids. “We may only see a small fraction of the total material in the asteroid belt,” she told Science News. .
There is a possible and expensive solution, Russell said: “We have to travel through space to get there.”
(Reprinted from The Epoch Times / Editor: Ye Ping)
URL of this article: https://www.ntdtv.com/b5/2024/11/07/a103927797.html
