On Sunday, a small space capsule was found in the Australian desert.
Inside this capsule was something truly special, something that all of humanity as we know it had only touched once before.
The asteroid inside was only the second one that humans have managed to get their hands on throughout history, and the sample — on its way to the lab in Japan — is on a new journey to transform scientific understanding of these space rock, and what they can tell us about our solar system.
Japan's asteroid-sampling spacecraft ended a five-year journey when it landed on the asteroid Ryugu on February 21, 2019. (Hayabusa2 arrived within range of Ryugu in June, 2018 and it spent more than a year orbiting its rocky companion, collecting observations and images of Ryugu before its final touchdown.)
The spacecraft collected a small sample from the rocky body before beginning its journey back to Earth. Once it arrived, Hayabusa2 dropped the 40-centimeter capsule back toward Earth on Friday night. It landed in the Woomera Prohibited Area — an area of land operated by the Royal Australian Air Force for military and civilian research — in southern Australia (interestingly, this area isn't exactly probhibited, you just need a tourist permit.)
How they found it — A collection team went searching for the capsule in the Australian outback by tracking the radio waves sent out by a radio beacon attached to the capsule.
JAXA had set up five antennas around an expected landing site that covers 38 square miles to help find the signal, and the agency also had a helicopter flying overhead with its own beacon receiver.
This marks Japan's second asteroid sampling mission, with the pioneer Hayabusa mission returning samples from asteroid 25143 Itokawa to Earth on June 13, 2010.
Why we study asteroids — Asteroids formed from the very same material that formed the Solar System, and may contain clues as to how water and other biological material made their way to Earth, and sparked life as we know it.
Most of what we know about asteroids comes from meteorites, which rain down to Earth as their parent comets and asteroids pass our planet. But this material may be significantly altered by virtue of Earth's atmosphere, water or weather. Therefore, snagging a piece of an asteroid as it flies through space provides scientists with pristine material from billions of years ago when the Solar System was in its infancy.
Another reason why scientists study asteroids is due to their potential threat.
Ryugu is a near-Earth, potentially hazardous asteroid that measures around 0.6 miles in diameter. The asteroid is on an elliptical orbit around the Sun every 16 months, where it happens to cross the orbits of Earth and Mars.
Space agencies keep a close watch on asteroids as they orbit the Solar System, fearing that one may be headed in Earth's direction.
What's next — After it dropped off the sample over Earth, the Hayabusa2 spacecraft headed towards its next stop; a smaller asteroid dubbed 1998KY26. The spacecraft will probe the ball-shaped asteroid in the year 2031, observing it without landing on it.
Meanwhile, NASA's OSIRIS-REx mission snagged a sample from asteroid Bennu in October, and the two space agencies will exchange pieces of their respective space rocks. NASA will receive a portion of JAXA’s sample from Ryugu, and will share samples from Bennu once they arrive on Earth in March, 2021.