Feeds

Boffin says Astronomical Unit should be binned

Fails to allow for shrinky sun, spiralling Earth

Secure remote control for conventional and virtual desktops

An astronomer based in Canada has published a paper arguing that distances within the solar system should no longer be measured using Astronomical Units (AU), which is currently standard practice.

An AU is approximately equal to the distance between Earth and Sun, but the International Astronomical Union actually defines it differently. According to the IAU, an AU's value is based on the Gaussian gravitational constant - which itself assumes that the Sun has a constant mass.

But Peter Noerdlinger of St Mary's University points out that in fact the Sun loses an ultra-minuscule proportion of itself every second due to the continual conversion of mass into solar energy. (About three millionths of a quadrillionth goes every second if we've got our sums right; or three billionths of a trillionth if you prefer. This equates to around six million tonnes, which is 60 US Navy aircraft carriers or 80-million-odd international adjusted Sarah Beenys completely annihilated.)

The Sun's shrinkage means that Earth gets further away and slows down in its progress all the time, gradually spiralling outwards into darkness and deviating from where it should be under IAU rules; which makes Noerdlinger mad.

"Units are not supposed to change," he told New Scientist, describing the situation as "quite a nuisance" and insisting that "for scientific and engineering usage, it is essential to get it right".

The testy boffin reckons variance in the AU could account for the so-called "Pioneer anomaly", in which NASA's Pioneer space probes have wandered off their calculated courses since heading out into interstellar space. He proposes using metres instead. ®

Internet Security Threat Report 2014

More from The Register

next story
MEN: For pity's sake SLEEP with LOTS of WOMEN - and avoid Prostate Cancer
And, um, don't sleep with other men. If that's what worries you
Voyager 1 now EIGHTEEN LIGHT HOURS from home
Almost 20 BEEELION kilometres from Sol
HUGE SHARK as big as a WWII SUBMARINE died out, allowing whales to exist
Who'd win a fight: Megalodon or a German battleship?
Jim Beam me up, Scotty! WHISKY from SPAAACE returns to Earth
They're insured for $1m, before you thirsty folks make plans
ROGUE SAIL BOAT blocks SPACE STATION PODULE blastoff
Er, we think our ISS launch beats your fishing expedition
Comet Siding Spring revealed as flying molehill
Hiding from this space pimple isn't going to do humanity's reputation any good
BAE points electromagnetic projectile at US Army
Railguns for 'Future fighting vehicle'
OK Google, do I have CANCER?
Company talks up pill that would spot developing tumors
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.
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.
Top 5 reasons to deploy VMware with Tegile
Data demand and the rise of virtualization is challenging IT teams to deliver storage performance, scalability and capacity that can keep up, while maximizing efficiency.
Mitigating web security risk with SSL certificates
Web-based systems are essential tools for running business processes and delivering services to customers.