Tiny particles of rock gathered from the asteroid are some of the most primordial bits of material ever examined on Earth and could give us a glimpse into the origins of the solar system.
The asteroid is in a circle around the sun between Earth and Mars and occasionally crosses Earth's path. Like other C-type asteroids, the carbonaceous, or C-type, asteroid spins like a top as it hurtles through space, and like other C-type asteroids, it likely contains material from the giant cloud of dust and gas that gave birth to the sun and its
In December of 2020, the samples were successfully transported to Earth in a container tucked inside a capsule. The results of the initial analysis of these remarkable bits of space rock are presented in two new papers.
Weird space rocks in our solar system are related to the 7 strangest asteroids.
"We are just at the beginning of our investigations, but our results suggest that these samples are among the most primordial material available in our laboratories," said Cédric Pilorget, an assistant professor in the Institute of Space Astrophysics at the Paris-Saclay University in France and first author of The age of the material should be revealed in future studies.
The asteroid samples have about 0.2 ounces of material. The largest particles of rock are about 0.31 inches across and the smallest are less than a millimeter in diameter. Toru Yada, an associate senior researcher at the Japan Aeronautical Exploration Agency and the first author of the second study, told Live Science that the samples looked like black pepper.
Yada and his colleagues kept the space rock in either a vacuum chamber or a sealed environment. He said that the samples have been handled without exposing them to the atmosphere. The samples were assessed using an optical microscope and various instruments that measured how the rocks absorb, emit and reflect different wavelengths of light.
The image is from the Wikimedia Commons.
The team found that the asteroid bits reflect 2% to 3% of the light that hits them. The researchers were surprised to find that the samples' bulk density was lower than that of known carbonaceous meteorites. The finding shows that the rocks are porous, meaning that there are many pockets of empty space between the individual grains of materials in the rocks.
According to Space.com, this finding is in line with preliminary data collected by the Hayabusa2 spacecraft, which suggests that the rocks on the surface of Ryugu are porous.
Pilorget and his team used a technique known as hyperspectral microscopy to take a closer look at the asteroid samples. Their microscope works by illuminating the samples with different wavelength of light in the visible and IR spectrum and snapping high-resolution pictures as it does. Each snapshot has about 0.2 by 0.2 inches and each individual pixel has data on the tiny scale. The team revealed details of the rocks' structure and chemical composition.
Snapshots of the samples showed that the rock particles are made of a "hydrated matrix" which includes clay and carbon-based compounds. Some of the material properties were close to those of the carbonaceous chondrites, which we have in our collections.
He said that the samples are among the darkest ever examined, and that they have to understand why and what it means regarding the formation and evolution of this material. The team discovered ammonia-rich compounds in the rock, which could have some implications for our understanding of primordial material.
The initial analyses represent the first step in figuring out what Ryugu can tell us about the early solar system, but exposing all of the space rocks' secrets will take some time. Pilorget said that a lot will come by combining additional techniques, in particular, the ones that will be capable of accessing the very fine scales.
The chronological history of when the asteroid first formed and when it came into contact with water will be revealed through chemical analyses. Key information about how the asteroid and its original body first formed will be provided by further assessments of the organic compounds and minerals in the samples. Yada said that researchers can examine the volatile compounds within the samples to see how solar winds shaped the asteroid's surface over time.
Pilorget said that they are only at the beginning of their investigations.
Live Science published the original article.
