Feeds

X marks the... They SAID there was a mystery planet there – NASA

WISE sky survey fails to find evidence of boffins' promised extra planet in Solar System

Security for virtualized datacentres

Boffins have long hypothesised the existence of a large, but thus far unseen, celestial body in our Solar System, somewhere beyond the orbit of Pluto, but NASA's WISE survey has found no sign of the mysterious "Planet X".

A nearby star stands out in red in this image from the Second Generation Digitized Sky Survey by WISE

Planet X, also known at various times as "Nemesis" or "Tyche", is a hypothesised large gas giant in the Oort cloud – a bunch of icy objects at the edge of the Solar System. Scientists have theorised about its presence because of a supposed bias in the points of origin for comets or the apparent discrepancies in the orbits of the known gas giants like Uranus and Neptune.

The idea that there could be another planet out there came in part from geological studies that suggested a regular timing for mass extinctions on Earth. Scientists suggested that this could be explained if there was a large planet or small star in the far reaches of the system that periodically swept through bands of outer comets, sending them hurtling towards our world.

Although the mass extinction theories were largely ruled out before NASA's Wide-field Infrared Survey Explorer (WISE) mission, astrophysicists from the University of Louisiana again proposed a missing gas giant in 1999 based on observations of comets with orbits of thousands to millions of years.

However, despite finding thousands of new stars in its survey of the sky, WISE was unable to spot any object the size of Saturn or larger to a distance of 10,000 astronomical units (1.49597871 × 1015m, or 9.29558073 × 1011 miles) and nothing bigger than Jupiter out to 26,000 AU. (An astronomical unit is roughly distance between our Earth and the Sun – approx 149 million km, or 93 million miles.)

"The outer Solar System probably does not contain a large gas giant planet, or a small, companion star," said Kevin Luhman of the Centre for Exoplanets and Habitable Worlds at Penn State University and author of a paper on WISE results for the Astrophysical Journal.

WISE's catalogue has come up with several thousand new bodies in the Sun's backyard - within 500 light years - including stars and brown dwarfs.

"We're finding objects that were totally overlooked before," said Davy Kirkpatrick of NASA's Infrared and Processing Analysis Centre at CalTech.

WISE did two full scans of the sky from 2010 to early 2011, capturing images of nearly 750 million asteroids, stars and galaxies. The AIIWISE programme enables astronomers to compare the two scans, taken around six months apart, to look for moving objects.

"We think there are even more stars out there left to find with WISE. We don't know our own Sun's backyard as well as you might think," said Ned Wright of the University of California, Los Angeles, the principal investigator of the mission. ®

Security for virtualized datacentres

More from The Register

next story
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
Thought that last dinosaur was BIG? This one's bloody ENORMOUS
Weighed several adult elephants, contend boffins
Europe prepares to INVADE comet: Rosetta landing site chosen
No word yet on whether backup site is labelled 'K'
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
Archaeologists and robots on hunt for more Antikythera pieces
How much of the world's oldest computer can they find?
prev story

Whitepapers

Secure remote control for conventional and virtual desktops
Balancing user privacy and privileged access, in accordance with compliance frameworks and legislation. Evaluating any potential remote control choice.
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.
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?
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
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.