Feeds

Hubble confirms planets are made from dust

Don't tell Kim 'n' Aggie

Build a business case: developing custom apps

Immanuel Kant was right: planets are formed from disks of dusty debris swirling around stars. NASA says images taken by the Hubble Space Telescope finally confirm Kant's prediction, made over 200 years ago.

The images, captured by Hubble back in 2000, show a planet orbiting in the same plane as its star's disk of dust. Over 200 examples of stars with extra solar planets have been found and there is no shortage of examples of young stars encircled by disks of debris. But prior to this Hubble image, there had been no evidence of both co-existing.

The planet orbits a Sun-like star called Epsilon Eridani, just 10.5 light-years from Earth in the constellation Eridanus. The planet's orbit is inclined 30 degrees to Earth, the same angle at which the star's disk is tilted.

In this, it is similar to our own solar system, where all the planetary orbits* are aligned. This has been interpreted as evidence that they all formed at the same time as the sun's disk. But Epsilon Eridani is much younger than our sun - only 800 million years old - so its disk has not yet dissipated, so both the planet and the Hubble confirm disks can co-exist.

The planet is the nearest extra-solar planet to Earth that has been found so far. It is now known to be around 1.5 times as massive as Jupiter, and it orbits its star every 6.9 years.

"Because of Hubble, we know for sure that it is a planet and not a failed star," Barbara McArthur of the University of Texas explained. She led the research along with her colleague G Fritz Benedict.

Making that deduction was not the work of five minutes. The team first identified the planet using the radial-velocity method. This measures tiny changes in a star's motion towards and away from Earth to infer the existence of unseen companions.

The team studied over a thousand astrometric observations from Hubble combined with other astrometric observations made at the University of Pittsburg's Allegheny Observatory. All this data was added to hundreds of ground-based radial-velocity measurements made over the past 25 years at various telescopes including the European Southern Observatory in Chile, and the McDonald Observatory at the University of Texas.

Their work is to be published in the November issue of the Astronomical Journal.

*Yes, all. See the demotion of Pluto for more details.

The Essential Guide to IT Transformation

More from The Register

next story
Just TWO climate committee MPs contradict IPCC: The two with SCIENCE degrees
'Greenhouse effect is real, but as for the rest of it ...'
Asteroid's DINO KILLING SPREE just bad luck – boffins
Sauricide WASN'T inevitable, reckon scientists
Flamewars in SPAAACE: cooler fires hint at energy efficiency
Experiment aboard ISS shows we should all chill out for cleaner engines
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
NASA Mars rover FINALLY equals 1973 Soviet benchmark
Yet to surpass ancient Greek one, however
Famous 'Dish' radio telescope to be emptied in budget crisis: CSIRO
Radio astronomy suffering to protect Square Kilometre Array
BEST BATTERY EVER: All lithium, all the time, plus a dash of carbon nano-stuff
We have found the Holy Grail (of batteries) - boffins
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Backing up Big Data
Solving backup challenges and “protect everything from everywhere,” as we move into the era of big data management and the adoption of BYOD.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.