The first look at Jackpot from the seven-year mission to bring back asteroid debris was revealed on Wednesday.
NASA officials in Houston displayed images of rocky salt and pepper chunks and dark space dust particles brought back to Earth from the asteroid Bennu, and described the first scientific observations of the material. The OSIRIS-REx mission ended in September when a capsule containing a collection of asteroid samples re-entered Earth’s atmosphere and was recovered in the Utah desert.
When technicians pried open the outer container, some material was found to have leaked out. Scientists were able to perform a rapid analysis and uncover some initial findings.
The asteroid debris contained waterlogged clay minerals. Their presence could help solve how Earth became a water planet. An asteroid similar to Bennu may have hit Earth and filled the oceans.
“The reason Earth is a habitable world, with oceans, lakes, rivers, and rain, is because clay minerals like those seen from Bennu landed on Earth four billion years ago,” says Professor Dante Lauretta. . The mission’s principal investigator, a professor of planetary science at the University of Arizona, said at a NASA event on Wednesday.
This material also contained sulfur, an element essential to many geological changes in rocks. “It determines how quickly something dissolves and is also important for biology,” said Dr. Lauretta, who showed microscopic images and 3D visualizations of the material. Scientists also discovered magnetite, an iron oxide mineral that can play an important role as a catalyst in organic chemical reactions.
“We’re looking at the types of minerals that may have played a central role in the origin of life on Earth,” Dr. Lauretta said.
The asteroid is also chock-full of carbon, a key building block for life. One sample contained 4.7 percent carbon by weight.
“We chose the right asteroid,” said Daniel Glavin, a NASA astrobiologist working on the mission. “Not only that, we brought back a suitable sample. This is an astrobiologist’s dream.”
The NASA mission that brought back the samples was named Osiris-Rex. It is short for Provenance, Spectral Interpretation, Resource Identification and Security, and Regolith Explorer. The mission ended on September 24, when a capsule containing fragments of Bennu fell under a parachute in the Utah desert. From there, the capsule was taken to the Johnson Space Center in Houston. Technicians there used a sample collection tool to remove the lid of the canister and found black powder and sand-sized particles.
“And already this is a scientific treasure,” Dr. Lauretta said.
This substance allowed for a quick and early look at what was inside, while slowing down entry into the main compartment of the sample collection tool.
“The only issue is the big one: We found a lot more samples than we expected,” said Frances McCubbin, curator of astronomical materials at the Johnson Space Center. I mentioned this before getting started. “We have to be very careful and carefully collect each grain. It will take a little while to get inside, but so far the view is great.”
For Moritza Montoya, one of the technicians, carefully collecting the samples meant using a spatula to push the powder into small piles and scooping them out with a small dustpan. “It’s literally a little dustpan,” Montoya said.
This leak generated a total of 1.5 grams of powder and particles.
“You can see it has a metallic sheen to it,” Montoya said. “So when you shine light on it, it reflects that light and sparkles.”
When the sample collector was turned over, larger chunks, including rocks, were revealed that were preventing the seal from closing completely.
“It’s a treasure chest full of extraterrestrial material,” Dr. Lauretta said.
Scientists still don’t know how much of it there is. It is hoped that after disassembling the device for a few more weeks, it will be able to be weighed. While the spacecraft was still in Bennu, engineers performed an operation that provided a rough estimate – 8.8 oz. It was hoped that Osiris-Rex would bring home at least 2.1 ounces.
Scientists plan to compare samples from Bennu with those brought back by Japan’s Hayabusa2 spacecraft from the similar asteroid Ryugu, but scientists have already noticed differences. For example, Ryugu contains almost no water.
Bennu, discovered in 1999, is a carbon-rich, almost black asteroid. It is approximately 1,600 feet wide. Comparably, the Empire State Building is 454 feet tall, including the top antenna. The carbon-rich material is interesting because asteroids like Bennu may have seeded Earth with the building blocks for life.
Osiris-Rex was launched in 2016 and arrived at Bennu a few years later to observe it from a distance. These remote discoveries led to the identification of carbonate minerals within the asteroid. Carbonate minerals typically form in environments containing both hydrothermal water and carbon dioxide. This suggests that Bennu’s larger object was once part of a hot spring or other extensive hydrothermal system. If so, there could be liquid water trapped in mineral pores for billions of years.
“We may actually be able to directly obtain samples of asteroid water,” Dr. Lauretta said.
In October 2020, OSIRIS-REx popped out of the asteroid and collected rock samples using a sampling tool that resembles a car air filter at the end of its robotic arm. A jet of nitrogen gas kicked up rocks and dust into the collection filter, and Osiris-Rex slowly retreated from Bennu without touching down.
The collection tool’s flap stopped opening and the collected rock and soil began to escape into space. Mission management decided to preserve the samples as soon as possible. In May 2021, the spacecraft began its return to Earth.
Using samples on the surface, researchers will measure the ratio of hydrogen to deuterium (a heavier form of hydrogen) and see if the ratio matches that found in Earth’s oceans. Scientists once thought that comets provided water, but most comets have a different ratio of hydrogen to deuterium than Earth’s.
Scientists will also look for amino acids, the building blocks of proteins, found in meteorites that have fallen to Earth.
However, meteorites that exist on Earth quickly become contaminated. “Microorganisms quickly become established,” says Dr. Lauretta. “
Bennu’s samples will allow scientists, for the first time, to observe amino acids used by living organisms from a pristine asteroid.
The sample could also help us understand why all life on Earth uses only one of two mirror images of amino acids and other complex organic molecules. If Bennu contains more of the mirror forms used by life, that suggests the universe has pushed its chances. If not, it could be other factors or just a coincidence.
Research on Osiris-Rex could also help protect Earth in the future.
Bennu is classified as a near-Earth asteroid, and scientists say it has a 1 in 1,750 chance of colliding with Earth during a series of very close passes between 2175 and 2199. .
Bennu is not large enough to cause the extinction of an entire planet. However, if there is a shock, it will be a disaster.
The mission is over, but the spaceship’s journey isn’t over yet. After releasing the return sample capsule, the main spacecraft deflected from a collision with Earth and is now headed for Apophis, a 1,000-foot-wide asteroid that will fly within 20,000 miles of Earth in 2029. Shortly after its approach, the spacecraft, now renamed Osiris-Apex (short for Origins, Spectral Interpretation, Resource Identification and Security-Apophis Explorer), will enter orbit around Apophis.
