Japan's ambitious second asteroid return mission, Hayabusa 2, has amassed a wealth of material from its destination Ryugu that astronomers and other interested parties are almost certain to be grappling with. While they may look like ordinary pieces of charcoal, they are real asteroid surface material – and something shiny too.
Hayabusa 2 was launched in 2014 and reached the asteroid Ryugu in 2018. At this point, he deployed a couple of landers to test surface conditions. It landed on itself the next year and blasted the surface with a space cannon so it could collect not only the surface gravel but what might be beneath it as well. After a long journey home, it reentered the atmosphere on December 5th and was collected in the Australian desert.
While everything worked perfectly, the team could never be sure that they would actually get the samples they were hoping for until they opened the sample collection containers in a sealed room at headquarters. The materials inside have been teased in a couple of tweets, but today JAXA released all of the public images along with some new explanations and discoveries.
For one thing, the “sample collector” had sediment grains from Ryugu itself. This material, which is exposed to different conditions than those of the container, may prove different when analyzed.
On the other hand, the sample container C appears to contain an "artificial object"! But don't get excited – as the team writes on their blog, "The origin is being investigated, but a likely source is aluminum scraped from the spacecraft's sampling horn when the projectile was fired to stir up material as it touched down."
In other words, it's likely part of the probe that came loose during the not-so-smooth process of shooting the asteroid and hitting it.
But the most important thing is all the stones that were collected as planned. As you can see from the scale bar, these are little more than pebbles, but they are large enough to provide evidence of all sorts of processes that lead to their particular shape and composition. There is also much smaller dirt and dust beneath the surface that scientists hope is showing signs of organic matter and water, the building blocks of life as we know it.
The success of the mission is worth celebrating, and the team has only just begun investigating the materials returned by Ryugu. Hence, we can expect more information once they do the careful analysis of these invaluable samples. The Hayabusa 2 Twitter account is probably the best way to keep up with the latest news day in and day out.