After spending six years in space, a Japanese Hayabusa2 spacecraft just landed in the desert south of Australia, carrying a bit of rocky asteroid to Earth’s surface. It’s the second time in history that material from asteroids returned to our planet. Eventually, scientists will open up the spacecraft, uncovering the precious rocks inside to learn more about asteroids penetrating our Solar System.
The landings are the culmination of Japan’s Hayabusa2 mission, which aims to bring samples of asteroids back to Earth. After launching from Japan in 2014, the Hayabusa2 spacecraft spent four years traveling to the asteroid called Ryugu. The vehicle spent a year and a half wandering around the asteroid, mapping rock faces, and sampling material before returning to Earth.
Scientists are eager to see the rock Hayabusa2 has returned because a pure sample of the asteroid can tell us more about what our Solar System was like when the planets first formed. That’s because asteroids look like baby photos from our cosmic environment. These space rocks have been around since the beginning of the Solar System, and scientists believe asteroids haven’t changed much over the past 4.6 billion years. These objects contain much of the same material that was at the birth of the Solar System, so studying these rocks in a laboratory on Earth can provide keys for the planet’s early days.
The capsule will transport to Japan, where we’ll learn how much asteroid material the mission gathered. The Japanese Aerospace Exploration Agency (JAXA), which oversees the mission, hoped to bring back 100 milligrams of material from Ryugu, but scientists have no way of measuring how many samples Hayabusa2 collects while in space. The exact number will reveal when the spacecraft opened up in Japan.
Japanese Hayabusa2 uses several creative techniques to collect its samples in Ryugu. With small horn-shaped arms, the spacecraft first tapped the asteroid in February 2019. When the arms touch, it fires a projectile like a bullet that pierces the asteroid, releasing all of the dust and pebbles who hopefully climb to the horn.
However, the spacecraft didn’t just take one sample at Ryugu. Hayabusa2 attempted this maneuver again in July 2019, but the spacecraft did a little digging first. Before tapping on the asteroid a second time, the spacecraft dropped a can of explosives on Ryugu, blasting a crater on the asteroid and revealing some of the rocks located just below the surface. Hayabusa2 then tapped the surface inside this crater to pick up some of this newly exposed material. The goal is to collect more pure stones from Ryugu. The material beneath the asteroid’s surface never exposes itself to the harsh space environment for billions of years, such as the outer rock, which is likely to undergo some changes and reactions over time. So the material from the crater can provide a better picture of the material that was present when the Solar System first formed.
After the Japanese Hayabusa2 team was sure they had taken a fair amount from Ryugu, the spacecraft left the asteroid in November 2019. After spending the final year traveling to Earth, the spacecraft deployed a small capsule late Friday night, with Ryugu’s sample located inside. The capsule then moves towards Earth, penetrating our planet’s atmosphere this morning. It then deployed a parachute, slowing the vehicle from about 12 kilometers per second, or nearly 27,000 miles per hour, so that it can land gently in the Woomera Forbidden Area in southern Australia.
After it hit, the ground teams from JAXA went on an extended search in Australia to find the capsule. The vehicle came down in an area that covers 100 square kilometers, or around 38 square miles. It also landed at nighttime in Australia, making the capsule even more challenging to spot. Fortunately, the capsule provided with a radio beacon that helped teams locate where the spacecraft touched down. Before the landing, JAXA teams set up five antennas around the expected landing site to help find the signal, and the agency also had a helicopter with its own beacon receiver to help narrow down the search. A drone was also on hand to fly overhead of the area to take pictures.
- China Chang’e 5 mission lands on the Moon
- SpaceX successfully launched its second crew into space on its first operational mission
Hayabusa2 is Japan’s second mission to sample asteroids. His first mission, Hayabusa, returned samples of asteroids to Earth in 2010, although the mission only succeeded in collecting tiny grains of asteroid material. Hopefully, Hayabusa2 will collect more than just the original Hayabusa offerings. And by 2023, NASA’s OSIRIS-REx mission is expected to return the largest sample of material from an asteroid ever collected.
Even though Hayabusa2 completed its main mission, the spacecraft was still not finished. The main spacecraft is still in space and has just started a search to visit another asteroid called 1998 KY26. Hayabusa2 took 11 years to reach its new target, to analyze space rock and learn more about the asteroids that surround us in space.