A new-and-improved successor to the troubled Japanese spacecraft Hayabusa – which finally returned a capsule to Earth earlier this year – could launch as soon as 2014. Hayabusa 2 would then be expected to return in 2020, bearing clues to the origin of life on Earth.

Last week, the Japan Aerospace Exploration Agency (JAXA) got the go-ahead from the government to begin development of Hayabusa 2, which will cost an estimated 16.4 billion yen ($2 billion).

Like its predecessor, it will visit an asteroid to collect dust samples. But whereas Hayabusa visited the 500-metre-wide asteroid Itokawa to collect silicon- and iron-rich dust, Hayabusa 2 will visit a kilometre-sized space rock called 1999 JU3, in search of organic molecules that might have seeded life on Earth.

It will also be designed to dodge the problems that Hayabusa encountered during its nail-biting and troubled mission. Although Hayabusa succeeded in delivering its capsule to Earth earlier this year, it’s not yet clear if it managed to collect asteroid dust as planned.


Hit and run

One new feature on Hayabusa 2 will be a 30-centimetre-wide bomb known as an impactor, says Makoto Yoshikawa, part of the Hayabusa 2 team at JAXA. When Hayabusa 2 is 500 metres from the asteroid, it will release the impactor and then retreat behind the asteroid “to hide”, says Yoshikawa. “Then the impactor explodes.”

The resulting 1-metre crater will enable samples to be taken from below the asteroid’s surface, where its material is less affected by solar radiation. Hayabusa aimed to take samples from Itokawa’s surface, but the subsurface material that Hayabusa 2 will sample is more likely to hold clues to the chemistry of the asteroid’s past.

To scoop up dust from this crater, Hayabusa 2 will deploy two different methods. Like its predecessor, it will have a small pellet to fire into the asteroid, kicking up dust for collection by a cone-shaped device. Hayabusa’s pellet failed to fire, however, so next time there will be a back-up.

The new spacecraft will also be designed to push a sticky, silicon-based material into the asteroid crater to gather extra dust. “If we have two kinds of sampling methods, we are sure to get more samples,” reasons Yoshikawa.

To help avoid other problems that dogged Hayabusa, the new asteroid probe will have backup orientation control systems, a better antenna and a redesigned engine.

Life from space

The dust gathered by this souped-up craft could tell us something about life’s origins. One theory as to how amino acids first arrived on Earth is that they hitch-hiked on asteroids or comets that bombarded our infant planet. But to prove this, researchers must first find amino acids on space rocks.

Last year NASA confirmed that its Stardust mission had captured amino acids from the tail of the icy comet Wild 2. But asteroid 1999 JU3, which thermal imaging indicates is rich in carbon compounds, is much closer to Earth and may therefore provide new insights into life’s origins.

Gentler touch

Jeremy Bailey, an astrophysicist at the University of New South Wales in Sydney, Australia, adds that landing on an asteroid and then collecting samples, rather than using Stardust’s fly-by catching method, might be a gentler and therefore more effective way to gather organic compounds.

He says that some organic material may have burned up when it smashed into Stardust’s collection gel at high speed.

Eventually, humans may get a chance to take such samples themselves. In April US president Barack Obama promised to send astronauts to an asteroid by 2025.

For now, the contents of the capsule that Hayabusa delivered to Earth are still being analysed.