Japan’s Hayabusa2 probe will on Wednesday leave orbit around a distant asteroid and head for Earth after an unprecedented mission, carrying samples that could shed light on the origins of the solar system.

Science and education minister Koichi Hagiuda told reporters Tuesday that the long voyage home will begin soon, with the probe expected to drop off its precious samples some time in late 2020.

The mission took the fridge-size probe some 300 million kilometers from Earth, where it explored the asteroid Ryugu, whose name means “dragon palace” in Japanese — a reference to a castle at the bottom of the ocean in an ancient fable.

In April, Hayabusa2 fired an impactor into the asteroid to shake up materials that had not previously been exposed to the atmosphere.

It then made a “perfect” touchdown on the surface of the asteroid to collect the samples, which scientists hope will provide clues into what the solar system was like at its birth some 4.6 billion years ago.

The six-year mission has a price tag of around ¥30 billion.

It took the probe 3½ years to get to the asteroid but the return journey should be significantly shorter because Earth and Ryugu are much closer due to their current positions.

Hayabusa2 is expected to drop the samples off in the South Australian desert, according to officials from the Japan Aerospace Exploration Agency (JAXA) and the Australian Space Agency.

The probe is the successor to JAXA’s first asteroid explorer Hayabusa, which means “falcon” in Japanese.

The earlier probe returned with dust samples from a smaller, potato-shaped asteroid in 2010 despite various setbacks during its epic seven-year odyssey, and was hailed as a scientific triumph.

KEYWORDS space, JAXA, astronomy, Hayabusa2