Most space rocks which arrive on Earth burn their way through our atmosphere. These rocks either vaporize or remain intact before crash landing—sometimes in someone's living room. However, one small chunk of space rock just made a much more dignified descent to Earth. Encased in a 15-inch capsule, samples collected from the asteroid Ryugu landed in the Australian outback on Saturday. Obtained by Japan Aerospace Exploration Agency (JAXA) using their Hayabusa2 spacecraft, the small samples will be interrogated by scientists who hope their contents can provide clues to the origins of planets and life within our Solar System.
In 2014, JAXA launched the Hayabusa2 on a multi-year mission to collect asteroid materials and return them safely to Earth. The asteroid Ryugu (meaning dragon palace) orbits the sun on a path between Mars and Earth. 190 million miles from Earth, the spacecraft reached the asteroid in 2018. Two samples were collected: a surface specimen and an internal specimen taken after blasting away the asteroid's surface. The small samples left the asteroid with Hayabusa2 in 2019 and spent a year in transit towards Earth. However, only the capsule itself returned to our planet. Ejected from 136,700 miles above Earth's surface, the capsule made its own descent while the spacecraft moves on to its next asteroid collection mission. Japanese scientists awaiting the capsule's descent have since collected the samples and begun extracting the gases contained within them. After this first research phase, the samples will be sent to Japan for further study.
The samples taken from Ryugu are of great interest to scientists. Meteorites are pieces of asteroids or meteoroids—space rocks of different sizes—which fall to Earth. However, while valuable for their metallurgic contents and other properties, these samples are damaged by their fiery descent through our atmosphere. The Ryugu samples, in contrast, have been preserved due to their specially designed capsule. As a result, scientists at JAXA hope to analyze the organic material contained within the samples. Asteroids date back to the Solar System's beginnings 4.57 billion years ago. Samples from Ryugu are therefore almost a time capsule themselves for the study of planetary origins. It is possible that the mineral, gas, and organic matter contained within the specimens will shed light on the numerous omnipresent questions of space exploration: the development of environments capable of sustaining life forms.