Feeds

Come off it, Moon, Earth. We KNOW you're 60 million years OLDER than we thought

'Might seem a small difference, but it is important,' say boffins

Internet Security Threat Report 2014

Geoboffins have cracked open some ancient crystals to discover that the Earth and the Moon are actually 60 million years older than previously thought.

Giant impact, common at the end of planet formation

You’d imagine that figuring out the age of the hunk of rock right under our feet would be something that scientists had done pretty conclusively by now, but it’s a lot harder than you think. Boffins say that because so little of the rock formations and other classic geological features from way back in deep time is still around today, it’s tough to narrow down just how old our planet is.

Scientists instead use the proportion of different gas isotopes that have survived from early on in our world’s history to try to figure out just when our Earth’s ancestor and another planet smashed into each other, creating modern-day Earth and its smallish satellite.

Two geochemists from the University of Lorraine in France now reckon that collision occurred around 40 million years after the Solar System first started to come together, rather than the previous figure of a hundred million years after the system’s formation.

Guillaume Avice and Bernard Marty peeked inside ancient samples of South African and Australian quartz, dated to 3.4 billion and 2.7 billion years ago respectively, and found xenon gas. The quartz acted like a time capsule, preserving the gas and allowing the researchers to compare modern isotopic ratios of xenon to the stuff that was around billions of years ago.

"The composition of the gases we are looking at changes according the conditions they are found in, which of course depend on the major events in Earth's history,” Avice explained.

“The gas sealed in these quartz samples has been handed down to us in a sort of ‘time capsule’. We are using standard methods to compute the age of the Earth, but having access to these ancient samples gives us new data, and allows us to refine the measurement.”

The maths then shows that the Moon-forming impact occurred around 60 million years earlier than scientists had previously thought, after which the Earth started to develop its atmosphere.

"This might seem a small difference, but it is important. These differences set time boundaries on how the planets evolved, especially through the major collisions in deep time which shaped the solar system,” Marty added.

The scientists presented their work to the Goldschmidt Geochemistry Conference in Sacramento, California. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
LIFE, JIM? Comet probot lander found 'ORGANICS' on far-off iceball
That's it for God, then – if Comet 67P has got complex molecules
Rosetta probot drilling DENIED: Philae has its 'LEG in the AIR'
NOT best position for scientific fulfillment
'Yes, yes... YES!' Philae lands on COMET 67P
Plucky probot aces landing on high-speed space rock - emotional scenes in Darmstadt
HUMAN DNA 'will be FOUND ON MOON' – rocking boffin Brian Cox
Crowdfund plan to stimulate Blighty's space programme
THERE it is! Philae comet lander FOUND in EXISTING Rosetta PICS
Crumb? Pixel? ALIEN? Better, it's a comet-catcher!
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Post-pub nosh neckfiller: The MIGHTY Scotch egg
Off to the boozer? This delicacy might help mitigate the effects
prev story

Whitepapers

Choosing cloud Backup services
Demystify how you can address your data protection needs in your small- to medium-sized business and select the best online backup service to meet your needs.
Getting started with customer-focused identity management
Learn why identity is a fundamental requirement to digital growth, and how without it there is no way to identify and engage customers in a meaningful way.
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.
Simplify SSL certificate management across the enterprise
Simple steps to take control of SSL across the enterprise, and recommendations for a management platform for full visibility and single-point of control for these Certificates.
Saudi Petroleum chooses Tegile storage solution
A storage solution that addresses company growth and performance for business-critical applications of caseware archive and search along with other key operational systems.