In the mission control room in Japan, all eyes were fixed on one of the large screens that ran along the far wall. The display showed the night sky, with stars twinkling in the blackness. We were waiting for a delivery from space.
Japan’s Hayabusa2 mission launched from the Tanegashima Space Center on December 3, 2014. The spacecraft was headed to asteroid Ryugu, with the intention of studying the tiny world and collecting a sample to return to Earth.
The mission would prove to be an incredible success. Not only did the spacecraft gather two samples from the asteroid, but it was the first mission to deploy autonomous rovers to explore an asteroid’s surface, generate an artificial crater in order to study the asteroid’s structure and collect a sample of the interior, and additionally, deploy a lander to make scientific measurements from the surface itself. The mission finale was to return the samples safely back to Earth on December 6, 2020. The grains in that sample container may hold clues as to how the Earth became habitable.
Ryugu is an example of a C-type or “carbonaceous” asteroid. These asteroids have undergone relatively little change since the start of the solar system, and are thought to contain hydrated minerals (minerals containing water in their structure) and possible organics. It is this class of asteroid that may have crashed into the early Earth and delivered the necessary tools for life to begin. Analysis of the Ryugu sample could therefore tell us about our own beginnings and how terrestrial planets develop habitable conditions.
As the Hayabusa2 spacecraft drew near the Earth, five “trajectory control manoeuvres” (TCMs) were planned. The first four of these were designed to put the spacecraft onto a collision course with the Earth, aimed at the Woomera desert in Australia. The re-entry capsule would then be released, and the spacecraft would make a final manoeuvre to divert onto an orbit that swept past the Earth and back into deep space.
Despite the smooth progress so far, there were concerns. The capsule release mechanism had not been tested since launch six years previously and it was always possible that separation would fail.… Read more