Japan is launching multiple missions to explore the mysteries of the solar system in the coming years, joining hands with the European Union and countries such as India to compete with space superpowers such as the United States and Russia.
The ultimate goal of space exploration is “to expand the areas of activities for humans and find another habitable planet. I believe there is a possibility that we can colonize Mars,” said Hitoshi Kuninaka, a vice president of the Japan Aerospace Exploration Agency (JAXA).
In 2018, Japan made history by landing two small rovers from the space probe Hayabusa2 on the surface of an asteroid 300 million kilometers from Earth. Hayabusa2’s touchdown on the Ryugu asteroid is expected in late January this year.
The probe’s aim is to collect a sample of sand on the asteroid that scientists believe could include some of the “raw materials” of the stars. This is based on the fact there is no atmosphere on the asteroid so its surface is thought to have remained almost unchanged since the birth of the solar system.
In October, the Japanese space agency worked with its European counterpart and successfully launched a spacecraft as part of efforts to explore Mercury. The probe is now on a 9 billion-kilometer voyage in space that will take seven years to complete.
The Mercury project is aimed at observing the planet’s atmosphere, magnetic field and surface to shed light on how the planet was formed.
“If we can compare Earth to Mercury, which has an environment inhospitable to life, we may discover the prerequisites for life to start,” said Go Murakami, assistant professor at JAXA.
In fiscal 2021, Japan plans to launch DESTINY+ (Destiny Plus) to observe dust in space that delivered organisms to Earth. JUICE, a craft that will orbit Jupiter and its moons, and MMX, designed to bring back materials from a Mars moon, are slated for launch in fiscal 2022 and 2024, respectively.
Though contributions made by Hayabusa2 and other missions last year have given momentum to Japan’s space exploration, the country went through a series of bitter failures in the late 1990s and early 2000s. Its first Mars explorer was trouble-ridden and could not enter the planet’s orbit, while a Japanese Venus explorer also failed its first attempt to enter orbit and took another five years to get back on course. In the meantime, China launched a probe to the moon and India to Mars, leaving Japan lagging behind.
Following these failures, Japanese researchers have worked hard to improve technologies. In 2010, Hayabusa2’s predecessor, Hayabusa, returned to Earth with surface samples from an asteroid for the first time ever. This paved the way for more missions.
Space missions require highly advanced technologies and a massive amount of funds, creating the need for more international collaboration. Japan has been exploring ways to work together with different partners, rather than just following the United States.
Johann-Dietrich Worner, director general of the European Space Agency (ESA) welcomed the collaboration with Japan on exploring Mercury, saying it is very valuable. Japan has also decided to work with India to study ice on the moon, said Hiroshi Sasaki, head of the JAXA Space Exploration Center.
Yet the competition is growing fierce. The moon, some 380,000 kilometers away from Earth, has been studied by researchers worldwide, especially since the 1969 Apollo 11 moon landing. After 50 years, the moon is now attracting renewed attention for research since the possibility has emerged that the ice found on both its south and north poles can be used as fuel and energy.
“China in particular is accelerating its efforts to explore the moon,” said Atsushi Uchida, a researcher at the Mitsubishi Research Institute.
It is thought the ice on the south and north poles of the moon can be used as fuels for rockets after being broken down into hydrogen and oxygen. It could also be utilized for drinking water on a future lunar base.
While countries such as the United States, Russia, China, India and South Korea, as well as the European Union, are attempting to study ice on the moon, Japan is planning to launch a lander dubbed SLIM in fiscal 2021.
The aim is to establish an accurate landing technology, so a lander can touch down at a location where solar cells can get sufficient sunlight. SLIM is expected to be able to check real-time images from a camera against a map of the surface of the moon, enabling the lander to self-estimate its location.
Researchers aim to establish technology that enables the lander to land at a certain location with an accuracy of hundreds of meters as a margin for error. The United States has already succeeded in landing to an accuracy of several to a dozen kilometers.
“We are aiming for an accuracy that has never been achieved by anyone,” said Shinichiro Sakai, associate professor at JAXA.
MMX, a space probe set to start traveling to one of Mars’ moons in about five years, will collect a sample of rock there and bring it back to Earth. Researchers say that by analyzing its composition, they could estimate where the moon was formed.
Mars is known to have traces of water, but it remains a mystery if a large amount of water could exist in liquid form on a planet that has such a thin atmosphere that it would be unable to retain water vaporized by the heat of the sun.
If MMX research results show that the moon was likely formed in a distant location with lower temperatures where water would have existed as ice before traveling to its current position, it would suggest the possibility that another astral body containing ice, similarly from far away, may have come into collision with Mars, supplying water to it. It could eventually explain why Earth, which is close to Mars on a galactic level, has water, according to researchers.
MIO, a probe developed in a joint project between JAXA and ESA, will observe the weak magnetic field that covers Mercury. The idea is to understand how strong a magnetic field needs to be for life to exist by comparing Mercury and Earth. “If we can figure out what the prerequisites are for life to exist, we will also know what we should prepare for when humankind make it to space in the remote future,” said Ichiro Yoshikawa, professor at the University of Tokyo.
JAXA’s Kuninaka said that Japan’s exploration of Venus has made progress, while its study on Mercury in collaboration with Europe has seen a good start. He expects further progress in the exploration of the solar system, including Mercury and Jupiter, over the coming decade.
The most recent challenge, he added, is to “establish technologies to safely land on the moon or Mars,” where the gravity is more powerful than on asteroids, making it harder to approach and land.
In the 2030s, one of Japan’s goals in space is to study Saturn, said Kuninaka.
“It takes longer to get there, while there is less sunlight to generate electricity for communication and observation. So we need to establish an energy-saving technology, which I believe will also help our lives on Earth,” he said.