Japanese Aerospace Exploration Agency (JAXA) launched a sample-return mission on asteroid Ryugu on 3rd December 2014. The probe is currently in surveying process of the asteroid and is scheduled return to Earth in 2020.

What is Hayabusa2?

Hayabusa2 is a Japanese asteroid exploration probe sent by JAXA on asteroid Ryugu. Following its partially successful predecessor Hayabusa, JAXA began work on improving its successor and addressed the weak points of the former.

With a mass of 610 kg including fuel, the power for its equipment is generated by solar arrays with operating efficiency of 2.6 kW at 1AU and 1.4 kW at 1.4 AU. To store the generated power, Hayabusa2 is equipped with eleven 13.2 Ah lithium-ion batteries. For communications, two high gain antennas for X band and Ka-band and connects with four space network stations across the globe.

The primary payloads of Hayabusa2 incorporate many scientific instruments for remote sensing, sensing and four rovers that will explore the surface and collect samples of the environmental and geographical context of the asteroid Ryugu.

The Rovers

Hayabusa2 carries four rovers to investigate the surface of Ryugu namely – MASCOT, ROVER-1A, ROVER-1B in MINERVA-II-1 container and ROVER 2 in the MINERVA-II-2 container. Due to the weak gravity of the asteroid, all the rovers are meant to hop, not roll on the surface as no wheels are attached to them.

The Rovers

Artist impression of three rovers – Rover-1A, 1B, and ROVER-2 on the surface of Ryugu

Hayabusa2 also deployed the rover developed by German and French space agencies – MASCOT which landed on the surface on 3rd October 2018 and worked for 17 hrs.

The first two rovers landed on the asteroid on 21st September 2018 and marked a historic achievement of being the first spacecraft to place robot rovers on the surface of the asteroid successfully. They are equipped with a wide-angle and stereo camera which send back the pictures of Ryugu. The spine-like projections on the rovers are sensors that are meant to measure the surface temperature.

Both the rovers are working fine and transmitting data to its mothership which then sends it back to the Earth.

Sample Return Mission

The probe Hayabusa2 is bound to land on the asteroid in October to collect the rock and soil samples. JAXA plans to detonate an explosive charge on the surface of Ryugu which will create a small crater. It is proposed to descend the probe into the crater to collect new rocks which are not altered by the exposure to the harsh environment of space.

Hayabusa 2 Return Mission

Image captured by Rover-1A during one of its hops

These samples would be collected and stored in three separate sealed containers inside the sample-return capsule (SRC). JAXA specially designs the SRC with thermal insulation and high-width packaging material. It is bound to leave Ryugu at the end of scientific research phase in December 2019 and deliver SRC in December 2020.

The purpose of the Hayabusa2 mission for scientists is to learn about the origin and composition of near-Earth objects and potentially hazardous asteroids of Apollo group. On getting back the samples, the scientists hope to find the answer to some fundamental questions about life and the universe. Are extraterrestrial objects responsible for the existence of life on Earth? The question remains unanswered.