Japan lands on an asteroid

Japan lands on an asteroid

The Japanese have achieved a space first: exploring an asteroid up close. 

The Japanese Space Agency probe, the Hayabusa 2, arrived in the vicinity of an Earth-approaching asteroid called 162173 Ryugu in June. The mission achieved a greater milestone on Sept. 21 when it deployed two “rovers” on the surface of the asteroid that are currently hopping about, taking images and temperature readings. 


By not only remotely examining an asteroid but, at the same time, exploring its surface, the Japanese have set a new precedent for asteroid exploration. The two rovers have already returned spectacular images from the asteroid’s surface. 

The landing of the two rovers is just the first of several feats that the Hayabusa 2 mission hopes to achieve.

While missions such as the Mars Curiosity, the Cassini, and New Horizons get a lot more of the headlines and attention from space enthusiasts, Hayabusa 2 is very important for human civilization for a variety of reasons.

From a scientific standpoint, Ryugu is an ideal target for a space mission as it is a primitive carbonaceous asteroid, containing a great deal of carbon, oxygen, water, and hydrogen, as well as cobalt, nickel, and iron. The asteroid is thought to contain some of the most pristine mix of materials dating from the beginning of the solar system. The study of Ryugu and its composition will provide insights into how the inner planets, including Venus, Earth, and Mars, were formed billions of years ago. 

Scientists will come to understand how the Earth was formed the way it was, with water, oxygen, and other materials that allowed for the rise of life.

Potential commercial space miners will find Ryugu valuable as well, with material estimated at a worth of almost $83 billion dollars. The water, carbon, hydrogen, and oxygen would be useful for future space colonists. Industrial-grade minerals such as iron and nickel could become the raw materials for space-based manufacturing.

Asteroid miners would send robots to extract useful materials from objects such as Ryugu and then transport them to space-based industrial facilities to be processed and used to build useful things. 

The material could be used to build huge communications arrays or space-based solar power collectors. A space-based factory could take advantage of microgravity, hard vacuum, and access to limitless solar energy to create useful products for export back to Earth.

Finally, the exploration of Ryugu is important because it is classified as a “potentially hazardous object.” Such objects orbit the sun close enough to the Earth’s orbit that they might potentially collide with our home planet. The most famous example of an asteroid collision with Earth was the object that smashed into the area of the Yucatan 65 million years ago, wiping out the dinosaurs.

More recently, an object called the Chelyabinsk Meteor entered the Earth’s atmosphere in February 2013 and exploded at a height of 18.5 miles over Chelyabinsk Oblast in the Urals in Russia, causing extensive damage and numerous injuries.

The idea of a dinosaur killer, something capable of wiping out the human race, hitting the Earth in modern times, has been the stuff of movies such as “Armageddon,” “Deep Impact” and TV shows such as “Salvation.” The study of objects such as Ryugu will help scientists develop strategies to divert or destroy objects in space should they become a threat to the Earth.

In the meantime, the mission of Hayabusa 2 is slated to continue through December 2020. Two more rovers, with different suites of instruments, are due to land on Ryugu. The Hayabusa 2 will take a number of samples from the asteroid’s surface and beneath the surface. Then in December 2019, the Japanese space probe, with its store of samples, will fire its ion engines to return to Earth. A year later, a reentry capsule with the samples will separate from the Hayabusa 2 and will reenter the Earth’s atmosphere, to land and be collected.

A team of international scientists at the Japanese Space Agency’s Extraterrestrial Sample Curation Center will then examine the samples — potentially a scientific treasure trove for our future in space.

Mark Whittington is the author of space exploration studies “Why is It So Hard to Go Back to the Moon? as well as “The Moon, Mars and Beyond.”