A small piece of building block that forms a comet formed inside a primitive comet. The discovery of the Carnegie Institution of Science-led team, including researchers at Arizona State University, Natural Astronomy.
Discovery can provide clues to the formation, structure, and evolution of the solar system.
"This meteorite is named LaPaz Icefield 02342," says research scientist Jemma Davidson of ASU's Center for Meteorite Studies at the Earth and Space Exploration School. "This name comes from the place found in the Lafarge Icefield in Antarctica."
She added that it belongs to a class of primitive carbon-mine meteorites that have undergone minimal changes since it was formed 4.5 billion years ago, perhaps beyond Jupiter's orbit.
The meteorite was part of an asteroid, a large body that once was destroyed by collisions in space and endured its journey through the Earth's atmosphere. Their composition can vary greatly from one meteorite to the next, reflecting their origins in various matrices formed in different parts of the solar system.
Asteroids and comets were once formed into a disk of gas and dust surrounding the young sun, but they gathered at different distances and influenced the chemical composition. Compared to asteroids, comets contain more water ice and much more carbon, and are generally formed away from the sun in colder environments.
By studying the chemistry and mineralogy of meteorites, researchers such as Larry Nittler of Carnegie, a senior author of the paper, can elaborate on how formation, heating, and other chemical treatments are formed during the formation of the solar system.
With the inner surprise, & # 39; Bonbon & # 39;
Inside the LaPaz meteor, Nittler's team found a very carbon-rich fraction of the raw material. It has some remarkable similarities with extraterrestrial dust particles that are thought to originate from comets formed near the outer edges of the solar system.
Though the solar system has been around for 3-35 million years, this small object (about a tenth of a millimeter) has been occupied by a growing asteroid of meteorite origin, while the earth is still growing.
"Primitive meteorites provide a snapshot of the early solar system that we can study in the lab," Davidson says. "LaPaz meteorites are a great example of experiencing extreme weathering."
The meteorite, like LaPaz, is a good place to find presolar grains, star-shaped miniscule formed by stars preceding the solar system. However, none of the teams expected to find evidence of a surviving comet building block inside the castle.
An ancient survivor
"When Larry and Carlos showed the first electronic image of a carbon-rich material, Davidson said," We knew we were seeing something very rare. It was one of the exciting moments you live as a scientist. "
Nittler and his colleagues through elaborate chemical and isotopic analysis – Davidson, Carnegie Conel Alexander and Rhonda Stroud of the US Naval Research Laboratory, Bradley De Gregorio, Josep Trigo-Rodríguez, Carles Moyano-Cambero Catalonia, Barcelona Space Science The Institute Safoura Tanbakouei appeared to be due to the ice-rich outer solar system along with objects of the Kuiper Belt with many comets.
"This space rock block sample was protected from invasion into the Earth's atmosphere because it was swallowed by an asteroid and stored inside this meteorite," explains Nittler. "It helped me to understand the chemistry of the solar system."
The presence of this raw material trapped inside the meteor implies that the drag caused by the surrounding gas moves the comet and the Kuiper Belt from the outer edge of the solar system formed closer to the nearby region of Jupiter, where carbonaceous chondrites form. This reveals details of how the solar system was formed in the early stages of planetary formation.
"This discovery shows how important it is to bring precious meteorites like LaPaz in Antarctica." We never know what secret they will reveal. "