Feeds

Asteroid Itokawa just a big lump of rubble

Not solid, as previously thought

Top 5 reasons to deploy VMware with Tegile

Itokawa asteroidAsteroid Itokawa - subject of a 2005 visit by Japan's Hayabusa probe - is nothing more than lump of rubble, new studies have shown.

The fact that the 535-metre asteroid is not solid as previously assumed has come as a bit of a surprise to those examining the Hayabusa data, New Scientist reports. Photographs reveal the body's surface "littered with boulders and gravel" which suggest it's comprised of the debris of an earlier asteroid collision.

Planetary scientist Erik Asphaug, of the University of California in Santa Cruz, said: "Five years ago, we thought that we would see a big chunk of monolithic rock, that something so small doesn't have the ability to hold onto any pieces. Everything we suspected about it turned out to be wrong."

Other evidence backs up the photographs: Hayabusa measurements of Itokawa's gravitational field, with its size factored in, reveal it's 40 per cent empty space. Asphaug describes this porosity as "astonishing", explaining: "It's very hard to get porosities greater than that. You've got to start balancing things delicately, like you were building a house of cards. The only way to do it is to gently pack the stuff together."

And therein lies the mystery, NS notes. Given its age, Itokawa should have become progressively less porous as repeated impacts "tamped down" the loose material. There's little evidence of impact craters on the surface, but that's believed to be because they're filled by gravel which is shaken down into the crater by post-impact vibration.

Hayabusa, meanwhile, is en route home - albeit with a three year delay. It successfully landed on Itokawa but whether or not it collected the intended samples remains doubtful. There's a report on its current status down at the Japan Aerospace Exploration Agency website. ®

Choosing a cloud hosting partner with confidence

More from The Register

next story
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
The next big thing in medical science: POO TRANSPLANTS
Your brother's gonna die, kid, unless we can give him your, well ...
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
NASA launches new climate model at SC14
75 days of supercomputing later ...
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
Simon's says quantum computing will work
Boffins blast algorithm with half a dozen qubits
LIFE, JIM? Comet probot lander found 'ORGANICS' on far-off iceball
That's it for God, then – if Comet 67P has got complex molecules
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
How to determine if cloud backup is right for your servers
Two key factors, technical feasibility and TCO economics, that backup and IT operations managers should consider when assessing cloud backup.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Choosing a cloud hosting partner with confidence
Download Choosing a Cloud Hosting Provider with Confidence to learn more about cloud computing - the new opportunities and new security challenges.