Feeds

Giant planet pileups in far-flung star systems: Computer says yes

Boffins crack stellar 'celebrity' migration riddle

Beginner's guide to SSL certificates

Top brainboxes armed with a British supercomputer say that they've cracked the riddle of just why it is that massive planets - spied across the vasty interstellar gulfs in recent times - tend to prefer certain orbits around their faraway parent stars.

"Our models offer a plausible explanation for the pile-ups of giant planets observed recently detected in exoplanet surveys," says Richard Alexander of Leicester uni.

It seems that known exoplanets, most of which are enormous gas giants on the lines of Jupiter or Saturn here in our solar system, are found mainly at distances around 1 Astronomical Unit (AU) from their own suns. This is the same distance as Earth is from our Sun.

We here on the Reg farflung-planets-glimpsed-across-the-vasty-gulfs-of-interstellar-space desk had sort of formed an unscientific impression that this might be because the techniques used to spot exoplanets struggle to see anything which is not a) vast and b) quite close to its parent star. But according to Alexander and his colleague Ilaria Pascucci of Arizona uni, this isn't true: as star systems form, they naturally tend to accumulate gas-giants at this sort of distance - our system is atypical in having them much further out.

"Our results show that the final distribution of planets does not vary smoothly with distance from the star, but instead has clear ‘deserts' – deficits of planets – and ‘pile-ups' of planets at particular locations," says Pascucci.

The two boffins' theory shows that as a young star system collapses onto its central sun, the interplay between the hot solar wind blasting material outward and gravity sucking it inward changes sharply according to distance bands, which results in a clear band from say 1 to 2 AU out. Gas-giant worlds naturally get moved inwards through this clear band and then achieve orbit once they hit the next band of dust and proto-stuff.

According to a Leicester uni statement announcing the new research:

Giant planets migrate inward before they finally settle on a stable orbit around their star. This happens because as the star draws in material from the protoplanetary disk, the planets are dragged along, like a celebrity caught in a crowd of fans.

However, the researchers discovered that once a giant planet encounters a gap cleared by photo-evaporation, it stays put.

"The planets either stop right before or behind the gap, creating a pile-up," explains Pascucci.

The two boffins confirmed their theory with the aid of some mighty number-crunching from the ALICE High Performance Computing Facility at Leicester uni. The resulting paper is to be published in hefty astro mag Monthly Notices of the Royal Astronomical Society, or you can read it online in advance here. ®

Top 5 reasons to deploy VMware with Tegile

More from The Register

next story
Bond villains lament as Wicked Lasers withdraw death ray
Want to arm that shark? Better get in there quick
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
The next big thing in medical science: POO TRANSPLANTS
Your brother's gonna die, kid, unless we can give him your, well ...
NASA launches new climate model at SC14
75 days of supercomputing later ...
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
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.
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.
Go beyond APM with real-time IT operations analytics
How IT operations teams can harness the wealth of wire data already flowing through their environment for real-time operational intelligence.
Why CIOs should rethink endpoint data protection in the age of mobility
Assessing trends in data protection, specifically with respect to mobile devices, BYOD, and remote employees.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?