Japan’s Hayabusa-2 starts orbiting asteroid

By Tom Risen|June 27, 2018

Orbiter will send a projectile toward the asteroid Ryugu to create a hole for a sample collection

Japan’s Hayabusa-2 spacecraft arrived in orbit around the asteroid Ryugu on Wednesday in the first step of a plan to gather a sample from within the asteroid by firing a projectile into its surface, said the Japan Aerospace Exploration Agency.

The resulting hole would expose material that Japanese scientists suspect could be as old as 4.6 billion years and contain compounds of carbon atoms. Scientists suspect that asteroids might have delivered such organic compounds, including amino acids to Earth, along with water, providing the building blocks for our carbon-based life.

“The Hayabusa-2 mission will, thus, be one that explores the origins of sea water and of life on Earth,” JAXA President Hiroshi Yamakawa tells me.

The probe, which was launched in 2014, will circle the asteroid to photograph and survey the surface with sensors including a thermal infrared camera and near-infrared spectrometer. During a series of brief touchdowns on the surface, the Hayabusa-2 will release a lander, called the Mobile Asteroid Surface Scout or Mascot, developed by German space agency DLR and French space agency CNES , and three Japanese-built Minerva 2 rovers, short for Micro-Nano Experimental Robot Vehicle for Asteroid. The rovers have no wheels but will instead take advantage of the low gravity to hop around the surface and make observations.

Hayabusa-2 will detach a detonation device armed with a projectile, and then move to the opposite side of the asteroid to avoid any debris as the device fires the projectile at Ryugu. The probe will then circle back around, land and collect samples from the fresh crater with a sampler horn on its base before propelling itself back into orbit with thrusters. The probe will fly back to Earth in 2020 and send a sample to the surface in a capsule.

Yamakawa says the design and methods of this asteroid sample collection could be useful for space companies that aim to mine asteroids. California-based Deep Space Industries was founded in 2013 with the goal of one day mining water from asteroids to provide oxygen and hydrogen for spacecraft fuel production or drinking water for deep space habitats.

To broaden the search for water or organic compounds in asteroids, Yamakawa says the next step after Hayabusa-2 could be to study different types of asteroids including “a bigger or smaller asteroid, or asteroid in a different orbit like those between Mars and Jupiter.”

Missions to explore asteroids also figure into space community discussions about how best to defend Earth from being hit by asteroids and potential massive ecological damage wrought by those collisions, Yamakawa says.

“To tackle hazardous asteroids, the first step is the observation of the asteroid and determine the orbit precisely and then that enables us to estimate the collision probability and the time frame,” he says. “The next step is to, of course, change the orbit of asteroid beforehand – well beforehand.”