Subscribe free to our newsletters via your
. 24/7 Space News .




EXO WORLDS
Exoplanet Caught On The Move
by Staff Writers
Paris, France (SPX) Jun 11, 2010


The above composite shows the reflected light on the dust disc in the outer part, as observed in 1996 with the ADONIS instrument on ESO's 3.6-metre telescope. In the central part, the observations of the planet obtained in 2003 and autumn 2009 with NACO are shown. The possible orbit of the planet is also indicated, albeit with the inclination angle exaggerated. Credit: ESO/A.-M. Lagrange

For the first time, astronomers have been able to directly follow the motion of an exoplanet as it moves from one side of its host star to the other. The planet has the smallest orbit so far of all directly imaged exoplanets, lying almost as close to its parent star as Saturn is to the Sun.

Scientists believe that it may have formed in a similar way to the giant planets in the Solar System. Because the star is so young, this discovery proves that gas giant planets can form within discs in only a few million years, a short time in cosmic terms.

Only 12 million years old, or less than three-thousandths of the age of the Sun, Beta Pictoris is 75% more massive than our parent star. It is located about 60 light-years away towards the constellation of Pictor (the Painter) and is one of the best-known examples of a star surrounded by a dusty debris disc. Earlier observations showed a warp of the disc, a secondary inclined disc and comets falling onto the star.

"Those were indirect, but tell-tale signs that strongly suggested the presence of a massive planet, and our new observations now definitively prove this," says team leader Anne-Marie Lagrange.

"Because the star is so young, our results prove that giant planets can form in discs in time-spans as short as a few million years."

Recent observations have shown that discs around young stars disperse within a few million years, and that giant planet formation must occur faster than previously thought. Beta Pictoris is now clear proof that this is indeed possible.

The team used the NAOS-CONICA instrument (or NACO), mounted on one of the 8.2-metre Unit Telescopes of ESO's Very Large Telescope (VLT), to study the immediate surroundings of Beta Pictoris in 2003, 2008 and 2009. In 2003 a faint source inside the disc was seen (eso0842), but it was not possible to exclude the remote possibility that it was a background star.

In new images taken in 2008 and spring 2009 the source had disappeared! The most recent observations, taken during autumn 2009, revealed the object on the other side of the disc after a period of hiding either behind or in front of the star (in which case it is hidden in the glare of the star).

This confirmed that the source indeed was an exoplanet and that it was orbiting its host star. It also provided insights into the size of its orbit around the star.

Images are available for approximately ten exoplanets, and the planet around Beta Pictoris (designated "Beta Pictoris b") has the smallest orbit known so far. It is located at a distance between 8 and 15 times the Earth-Sun separation - or 8-15 Astronomical Units - which is about the distance of Saturn from the Sun.

"The short period of the planet will allow us to record the full orbit within maybe 15-20 years, and further studies of Beta Pictoris b will provide invaluable insights into the physics and chemistry of a young giant planet's atmosphere," says student researcher Mickael Bonnefoy.

The planet has a mass of about nine Jupiter masses and the right mass and location to explain the observed warp in the inner parts of the disc. This discovery therefore bears some similarity to the prediction of the existence of Neptune by astronomers Adams and Le Verrier in the 19th century, based on observations of the orbit of Uranus.

"Together with the planets found around the young, massive stars Fomalhaut and HR8799, the existence of Beta Pictoris b suggests that super-Jupiters could be frequent byproducts of planet formation around more massive stars," explains Gael Chauvin, a member of the team.

Such planets disturb the discs around their stars, creating structures that should be readily observable with the Atacama Large Millimeter/submillimeter Array (ALMA), the revolutionary telescope being built by ESO together with international partners.

A few other planetary candidates have been imaged, but they are all located further from their host star than Beta Pictoris b. If located in the Solar System, they all would lie close to or beyond the orbit of the furthest planet, Neptune. The formation processes of these distant planets are likely to be quite different from those in our Solar System and in Beta Pictoris.

"The recent direct images of exoplanets - many made by the VLT- illustrate the diversity of planetary systems," says Lagrange. "Among those, Beta Pictoris b is the most promising case of a planet that could have formed in the same way as the giant planets in our Solar System."

.


Related Links
European Southern Observatory
Lands Beyond Beyond - extra solar planets - news and science
Life Beyond Earth






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








EXO WORLDS
'Out Of Whack' Planetary System
Houston TX (SPX) May 28, 2010
The discovery of a planetary system "out of whack," where the orbits of two planets are at a steep angle to each other, was reported by a team of astronomers led by Barbara McArthur of The University of Texas at Austin McDonald Observatory. This surprising finding will affect theories of how multi-planet systems evolve and shows that some violent events can happen to disrupt planets' orbit ... read more


EXO WORLDS
NASA Langley to Break Ground on Hydro Impact Basin

The Earth And Moon Formed Later Than Previously Thought

Old Moon Rover Beams Surprising Laser Flashes To Earth

MSU Robot Digs Most Moon Dirt

EXO WORLDS
Radar system tested for Mars rover landing

Mapping Project Consistent With Huge Historic Seas On Mars

Detailed Martian Scenes In New Images From Mars Orbiter

Mars500 - Eighteen Months In Isolation

EXO WORLDS
Continued Development On 18 Small Business Tech Transfer Projects

ESA Astronauts At ILA In Berlin

Doctor Needed In Antarctica

A Chance To Name Europe's Next Astronaut Mission

EXO WORLDS
China eyes Argentina for space antenna

Seven More For Shenzhou

China Signs Up First Female Astronauts

China To Launch Second Lunar Probe This Year

EXO WORLDS
Russian Mission Control Raises ISS Orbit

ISS Orbit Adjusted Prior To Soyuz Spacecraft Docking

ISS Expedition 23 lands safely in Kazakhstan

China May Become Space Station Partner

EXO WORLDS
South Korea Delays Rocket Launch

SpaceX Achieves Orbital Bullseye With Inaugural Flight Of Falcon 9 Rocket

Pratt and Whitney Rocketdyne Celebrates 50 Years

Space Industry Leaders And Astronauts Congratulate SpaceX

EXO WORLDS
Exoplanet Caught On The Move

'Out Of Whack' Planetary System

Weird Orbits Of Neighbors Can Make 'Habitable' Planets Not So Habitable

Get It While it's Hot! Star Devours Planet

EXO WORLDS
Second Life creator Linden Lab laying off staff

Zynga launches new Facebook game, 'FrontierVille'

Asian computer firms betting on a 3D future

Integral Systems Awarded Contract To Support LS1300




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement