Feeds

Galaxy is teeming with homeless planets

Born under a wandering star…

Beginner's guide to SSL certificates

The galaxy – and presumably, if we’re in a normal-enough galaxy, the rest of the universe – has a bit less empty space than we thought, according to a study by the Kavli Institute for Particle Astrophysics (KIPAC).

The research suggests the Milky Way could hold many millions of “nomad planets” – many thousands existing for each main-sequence star in the galaxy.

KIPAC – a joint institute of Stanford University and America’s SLAC National Accelerator Laboratory – is suggesting that nomad planets could outnumber stars in the Milky Way, by as much as 100,000:1.

Over recent years, gravitational microlensing (the refocusing of a star’s light by planets passing “in front” of them) has provided new insights into planets that don’t appear to be bound to stars.

Louis Strigari, leader of the team that reported the results to the Royal Astronomical Society, suggests that some of the planetary orphans could even retain enough heat for microbial life – if they have enough tectonic and radioactive processes to generate heat and enough atmosphere to retain it.

Most of the 500-odd exoplanets discovered in the past two decades orbit stars, but last year, astronomers turned up a dozen nomad planets that don’t orbit stars. Some may have been ejected from the solar systems in which they formed; others may need to be explained with new theories of planetary formation.

However, Strigari believes known values like the mass of the galaxy (estimated from its gravitational pull) mean it could be “teeming” with nomad planets. As new instruments like the ground-based Large Synoptic Survey Telescope and the space-based Wide-Field Infrared Survey Telescope, both of which will come into service during the 2020s, will provide the kind of observations that will drive new estimates of the number of nomads, Strigari’s paper states.

Strigari also speculates that nomad planets, if they are able to harbor life, could also provide a vector for scattering it through the galaxy. He is, however, clear that such ideas are speculative. ®

Internet Security Threat Report 2014

More from The Register

next story
GRAV WAVE DRAMA: 'Big Bang echo' may have been grit on the scanner – boffins
Exit Planet Dust on faster-than-light expansion of universe
SpaceX Dragon cargo truck flies 3D printer to ISS: Clawdown in 3, 2...
Craft berths at space station with supplies, experiments, toys
That glass of water you just drank? It was OLDER than the SUN
One MEELLION years older. Some of it anyway
Big dinosaur wowed females with its ENORMOUS HOOTER
That's right, Doris, I've got biggest snout in the prehistoric world
Japanese volcano eruption reportedly leaves 31 people presumed dead
Hopes fade of finding survivors on Mount Ontake
Relive the death of Earth over and over again in Extinction Game
Apocalypse now, and tomorrow, and the next day, and the day after that ...
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.
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
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.