The Japanese space probe Hayabusa 2 scratched on and below the surface of the asteroid Ryugu – and resorted to a brutal method twice: It blasted craters into the surface of Ryugu.
5.4 grams of loot are in this transport container: It was collected on the asteroid Ryugu.
Then Hayabusa 2 touched down on Ryugu briefly and took the soil samples with a kind of oversized vacuum cleaner pipe in order to bring them back to earth safely in a small container. In December 2020 she delivered her precious cargo on earth. The discarded sample capsule contained 5.4 grams of “black sand-like particles” – about a teaspoon full of asteroid crumbs. The material comes from the early days of the solar system. The scientists hope that the samples will not only provide more information about Ryugu and other asteroids. They also promise to gain knowledge about the origin of the solar system and life on earth.
“It really is like a dream. After 5.2 billion kilometers of space travel that lasted six years, the capsule has returned. And now it is here with us.”
Yuichi Tsuda, project manager of the Hayabusa 2 Mission
Profile: Asteroid 162173 Ryugu (1999 JU3)
Orbit of asteroid Ryugu (1999 JU3). Hayabusa, the predecessor of Hayabusa 2, had visited the asteroid Itokawa.
It is pitch black and around 4.5 billion years old. The asteroid Ruygu has a diameter of around one kilometer and belongs to a common class of near-Earth asteroids. Telescope observations from Earth suggested that it may contain water. If that’s true, it would be evidence that water once came to our planet through asteroid impacts.
Ryugu was discovered on May 10, 1999 and is also called 1999 JU3. The asteroid has only been called “Ryugu” since September 28, 2015: The Japanese space agency JAXA had publicly called for a name. One suggestion was “Ryugu” – that’s the name of the underwater palace of a dragon god in Japanese sagas.
Why you wanted to scratch an asteroid
Looks like a meteorite, but it is the fall of the sample from the asteroid Ryugu collected by Hayabusa 2
Asteroids like Ryugu are considered to be the most pristine material that our solar system still has to offer around 4.5 billion years after its formation: because while planets have gone through a lot during and since their formation, asteroids remained largely undisturbed as remnants of the exciting times. Therefore, their composition and nature should provide information about how our solar system was formed.
Sometimes planetologists are lucky: Then just such an interesting chunk falls on earth all by itself, for example the famous Murchison meteorite in 1969. However, such a collision with our earth’s atmosphere is not without consequences, which is the untouched nature of the material concerns – and researchers cannot choose what exactly falls where on earth.
In the case of Ryugu, there were already indications from remote sensing methods that this asteroid must have remained very original. The samples he collected during the Hayabusa 2 mission could possibly contain organic material. The focus is on amino acids, which are the fundamental building blocks of life. Analyzes should also clarify, for example, whether asteroids like Ryugu brought large amounts of water to Earth when they hit the ground. The exact analysis will take years, however.
The meaning of the names “Hayabusa” and “Ryugu”
A fisherman receives a mysterious box in the palace of the dragon god called Ryugu-jo. What’s in there?
A peregrine falcon flies to an underwater palace and comes back with a box full of mysterious things. At least the Japanese names of the mission tell this story. Translated from the world of legends into space it means: The probe Hayabusa 2 (“Peregrine Falcon 2”) flies to the asteroid Ryugu (underwater palace of a dragon god) to take material samples and bring them to earth.
In a Japanese legend, a fisherman comes to this palace called Ryugu-jo: There, Princess Otohime gives him a mysterious box, including instructions not to open it after his return to the human kingdom. Of course, the Japanese space agency JAXA does not take the legends that literally: Because the sample container that Hayabusa 2 sent to Earth was opened with great care. After all, the aim of the mission is to analyze the approximately 5.4 grams of asteroid material. Nor is it to be assumed that any of those involved have turned into an old man – not like the curious fisherman from the Japanese legend.
The German MASCOT lander also hopped over Ryugu
Ryugu’s valuable booty is now being carefully analyzed
JAXA provides sample material from Ryugu
The samples were initially roughly curated and described. The more precise microscopic, mineralogical and geochemical analyzes began in mid-2021. JAXA has already made some of the samples available to NASA: the US space agency received around ten percent of the material collected, namely 23-millimeter-sized granules and four containers with even finer material. From 2022, samples will also be made available to researchers in other countries. Also the DLR is planning investigations.
5.4 grams of asteroid are examined in great detail
Earth scientists were able to collect their first findings about Ryugu even before Hayabusa 2 sent the samples to Earth: Among other things, the German MASCOT lander explored the asteroid and radioed the data towards Earth. The analysis of the samples, however, will take years. First of all, methods are used in which the valuable sample material does not have to be destroyed.
The Hayabusa 2 mission has been running since 2014
Hayabusa 2 war on behalf of the Japanese space agency JAXA launched from Japan on December 3, 2014. After a journey of almost four years, the probe reached its first destination, the asteroid Ryugu, on June 27, 2018, after traveling around three billion kilometers. At the time, it was about 285 million kilometers away from us. Samples were taken in 2019, and the samples landed safely on earth at the end of 2020.
Hayabusa 2 is already on its way to the next asteroid
On the trip, Hayabusa 2 can photograph the zodiacal light: This enables researchers to learn more about interplanetary dust.
The Ryugu expedition from Hayabusa 2 lasted six years. After the samples were dropped on earth in December 2020, it continued its mission: The probe of the Japanese space agency is now on its way to the near-earth asteroid “1998KY26”. In contrast to Ryugu, this asteroid is tiny: 1998KY26 is only around 30 meters in diameter. Hayabusa 2 is scheduled to arrive at this micro-asteroid in July 2031.
A look into our past and future
NASA-Mission Osiris Rex
NASA has also started a mission to an asteroid to explore and take samples: Osiris Rex. The probe is scheduled to return to Earth in 2023. Then NASA and JAXA want to exchange and compare samples.
Asteroids are considered to be remnants from the early days of our solar system. Hence, researchers are keen to learn what these are made of. This enables a look back into the cosmic past and the formation of the earth, the oceans and life. Asteroids are also interesting for asteroid mining (space mining) because they offer raw materials that are rare on earth. At the same time, especially near-earth objects, including Ryugu, represent a potential threat to humanity. Even if he himself will never be dangerous to Earth, it would be helpful for future defense missions if researchers learn more about asteroids like Ryugu.