China's Astronomy 2 asteroid sample regression mission is scheduled for May 2025 on the way to the asteroid Kamo'oalewa (2016 HO3). The country can join the United States and Japan, and their space agencies have both successfully retrieved a sample from the asteroid in order to return to Earth.
Previously several space missions for asteroids flying and peeked at their works, but bringing samples back to Earth was more helpful for scientists. The most useful analysis requires poking physical samples into and product, glowing, running through a CT scanner and examining under an electron microscope.
These missions require detailed planning and dedicated spacecraft, so to clarify why agents are in trouble, we compiled four stories from our archives from the conversation. These articles describe how asteroid sample returns missions generate new scientific insights at each stage—from the collection process to the return of containers to the laboratory analysis.
1. Ryugu's colorful history
The asteroid Ryugu is made of carbon-rich rocks. Japan targets Ryugu for 2020 samples to return to Hayabusa2.
As Paul K, a planetary scientist at Washington University in St. Louis, this process allows the Hayabusa2 spacecraft to collect samples to take home and carefully observe the surface of the asteroid.
One thing the collection team noticed was that the material flying out of the asteroid was redder than the surface of the shot, with a blue scent.
Some parts of Ryugu are almost striped - the mid-latitude is red, while the poles look bluer. The sample collection process provides some hints for researchers.
"At some point, the asteroid must have been closer to the present sun," Bourne wrote. "This will explain the amount of redness on the surface."
Read more: Touching the asteroid Ryugu reveals secrets and changing orbits on its surface
2. Return to the capsule to cause shock wave
Similar to researchers obtaining valuable data from the Hayabusa2 collection process only, atmospheric scientists don’t even need to turn on Osiris-Rex samples to return to capsules to learn new knowledge.
NASA's Osiris-Rex mission heads to the carbon-rich asteroid Bennu and returns home in September 2023 with a small capsule containing samples.
The sample return capsule was released from the Osiris-Rex aircraft and pierced into the earth in a heavy box about the size of a microwave. Except that it has been released from a spacecraft of about 63,000 miles (102,000 kilometers), the return looks very similar to the spacecraft where the meteorite hits Earth.
Scientists often do not need to inform in advance to study how real meteors (the term given before a meteorite hits the ground) manifest themselves when they enter the atmosphere, so they jumped on the opportunity to study capsules when they return to Earth.
As physicists Brian Elbing of Oklahoma State University and Elizabeth A. Silber of Sandia National Laboratories discuss in their article, the reentry of the Osiris-Rex is a great opportunity to study what happens in the atmosphere when a meteor-sized object flies.
The teams built a network of sensitive microphones and other instruments, whether on the ground or attached to a balloon, to record the frequency of sound waves generated by the capsule in the atmosphere. Understanding how waves spread in the atmosphere can help scientists figure out how to detect hazards such as natural disasters.
Read more: NASA's asteroid sample mission provides scientists around the world with a rare opportunity to learn artificial meteors
3. The foundation of Bannu's life
Once Osiris-Rex returned to the capsule safely back on Earth, researchers around the world — including Smithsonian geologist Timothy J. McCoy and planetary scientist Sara Russell (from the British Museum of Natural History) from the UK — conducted work tests on their contents while carefully processing the samples to avoid contamination.
As they described in the article, McCoy and Russell found that the sample was primarily water-rich clay, which they hoped was a carbon-rich asteroid. But they also found surprisingly salty and salt water-related minerals. These minerals form when water evaporates from the surface of the rock.
Because these minerals (properly known as evaporators) dissolve when in contact with moisture, scientists have never seen them in meteorites flying over Earth's atmosphere, even similar components to Bennu. The spacecraft's sample container keeps Bennu sample sealed so that these evaporates remain intact.
These results suggest that the asteroid was once wet and muddy. Saltwater environments like Bennu may have been a good place for organic molecules to form. Some scientists predict that Earth has acquired the components of life from collisions with asteroids like Bennu.
Read more: Bennu asteroid reveals its content to scientists - and how the foundation of life may have been sown
4. Looking forward: Asteroid Mining
The asteroid sample return mission generates many scientific insights. They can also help space agencies and companies understand what exactly is there to take home from an asteroid. While carbon-rich asteroids like Bennu and Ryugu don't blend with precious metals, other asteroids have more valuable content.
NASA's Psyche Mission, launched in 2023, is currently traveling through space and will explore metal asteroids. Psychological asteroids may contain platinum, nickel, iron and possibly gold – materials of all commercial interest.
Scientists can form and form the core of Earth from metal asteroids such as Medice, which is the main goal of the mission. But, as Valerie Payré, a planetary scientist at the University of Iowa, wrote in her article: “Psychological tasks are an important step in figuring out which metal.”
Currently, commercial asteroid mining operations are science fiction – not to mention legally annoying. But some companies have begun to think about early plans of what to do one day. Asteroid sample missions can be made in advance.
Read more: NASA's robot prospectors are helping scientists understand that asteroids are made of asteroids - setting a stage for miners
This story is a review of articles in the dialogue archive.