Feeds

Boulder boffins reveal secret of gas giants' moons

Neptune still a puzzle, though

Business security measures using SSL

A computer model developed by scientists at the Southwest Research Institute in Boulder, Colorado, sheds new light on the formation of many of the moons in the solar system.

Up until now, according to the research team, it has been known that collectively, the moons of Jupiter, Saturn and Uranus amount to a similar proportion of their parent planet's mass - around 0.01 per cent.

What has not been clear is why that should be, or why the moons are the sizes that they are, or distributed in the orbits that they inhabit. Existing models also fail to account for why some of the moons contain ice, as they suggest moons form too quickly (and therefore at too high a temperature) to acquire a watery component.

According to New Scientist the model developed by Robin Canup and her colleague William Ward produces gas giants with moon sizes and distributions consistent with real-world examples.

The model also explains the apparent upper limit on the mass of the moons.

In the final stages of a gas planet's formation, it is thought to accrete both gases and solids from a disk of such debris orbiting the sun. This then forms a disc around the planet, in the equatorial plane, which in turn give rise to growing satellites.

According to Canup and Ward, as these satellites grow, they induce spiral waves in the gas disk. The interactions between these waves and the proto-moons cause the orbits to contract. Heavier moons' orbits contract more quickly, and collapse into the planet itself, while smaller moons stabilise in their orbits.

The researchers also suggest many cycles of moon formation and loss. The moons we see today are merely the last ones standing, according to Physorg.com.

Uranus, however, remains something of a mystery. The researchers believe that the key to understanding its arrangement lies in working out how it came to be lying on its side. Only then will they know for sure whether this new model will apply. ®

Providing a secure and efficient Helpdesk

More from The Register

next story
PORTAL TO ELSEWHERE scried in small galaxy far, far away
Supermassive black hole dominates titchy star formation
Boffins say they've got Lithium batteries the wrong way around
Surprises at the nano-scale mean our ideas about how they charge could be all wrong
Edge Research Lab to tackle chilly LOHAN's final test flight
Our US allies to probe potential Vulture 2 servo freeze
Europe prepares to INVADE comet: Rosetta landing site chosen
No word yet on whether backup site is labelled 'K'
Cracked it - Vulture 2 power podule fires servos for 4 HOURS
Pixhawk avionics juice issue sorted, onwards to Spaceport America
City hidden beneath England's Stonehenge had HUMAN ABATTOIR. And a pub
Boozed-up ancients drank beer before tearing corpses apart
'Duck face' selfie in SPAAAACE: Rosetta's snap with bird comet
Probe prepares to make first landing on fast-moving rock
prev story

Whitepapers

Providing a secure and efficient Helpdesk
A single remote control platform for user support is be key to providing an efficient helpdesk. Retain full control over the way in which screen and keystroke data is transmitted.
WIN a very cool portable ZX Spectrum
Win a one-off portable Spectrum built by legendary hardware hacker Ben Heck
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.
Protecting users from Firesheep and other Sidejacking attacks with SSL
Discussing the vulnerabilities inherent in Wi-Fi networks, and how using TLS/SSL for your entire site will assure security.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.