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Descubren otros 32 planetas nuevos fuera de las fronteras del Sistema Solar

Un grupo internacional de investigadores ha descubierto 32 nuevos exoplanetas (fuera de los límites del Sistema Solar) desde el observatorio de La Silla, al norte de Chile, lo que ayudará a comprender mejor el Sistema Solar y el universo.

Así lo ha anunciado este lunes Michel Mayor, del Observatorio de Ginebra (Suiza), e integrante de este equipo, quien ha sido invitado a dar una conferencia por la Fundación Ramón Areces y la Real Academia de Ciencias, que han reunido en unas jornadas a destacados astrónomos.

Los exoplanetas son cuerpos que giran en una órbita permanente alrededor de una estrella, pero más allá del Sistema Solar. Mayor fue quien halló -en 1995- el primer planeta alrededor de otra estrella como el Sol y luego otros muchos.

En los últimos 15 años se han descubierto 350 planetas orbitando estrellas parecidas al Sol, lo que ha revelado la existencia de una impresionante diversidad de exoplanetas, ha detallado este científico.

Telescopio europeo

El descubrimiento de los 32 nuevos exoplanetas ha sido realizado gracias a las mediciones realizadas por el High Accuracy Radial Velocity Planet Searcher (HARPS o Buscador de Planetas por Velocidad Radial de Alta Precisión), instalado en el telescopio de 3,6 metros de la ESO (Organización Europea para la Investigación Astronómica), en La Silla.

Este descubrimiento ha sido anunciado simultáneamente en Madrid y en Oporto (Portugal), en un congreso científico. Además de Mayor, intervienen en estas jornadas Michel Brown, descubridor de los principales cuerpos transplutonianos.

“Lo más interesante es que aún hay muchos objetos más allá de Plutón”, ha remachado este investigador del Instituto de Tecnología de California (EE UU), quien ha afirmado tener la confianza en que en los próximos años “aprenderemos más” sobre el universo.

www.20minutos.es

ESOcast 11: 32 New Extrasolar Planets Found.

On 19 October 2009, at an international ESO/CAUP exoplanet conference in Porto, the team who built the High Accuracy Radial Velocity Planet Searcher, better known as HARPS, the spectrograph for ESO’s 3.6-metre telescope, reports on the incredible discovery of some 32 new exoplanets, cementing HARPS’s position as the worlds foremost exoplanet hunter.

This result also increases the number of known low-mass planets by an impressive 30%. Over the past five years HARPS has spotted more than 75 of the roughly 400 or so exoplanets now known.

“HARPS is a unique, extremely high precision instrument that is ideal for discovering alien worlds,” says Stéphane Udry, who made the announcement. We have now completed our initial five-year programme, which has succeeded well beyond our expectations.

The latest batch of exoplanets announced today comprises no less than 32 new discoveries. Including these new results, data from HARPS have led to the discovery of more than 75 exoplanets in 30 different planetary systems.

In particular, thanks to its amazing precision, the search for small planets, those with a mass of a few times that of the Earth — known as super-Earths and Neptune-like planets — has been given a dramatic boost. HARPS has facilitated the discovery of 24 of the 28 planets known with masses below 20 Earth masses. As with the previously detected super-Earths, most of the new low-mass candidates reside in multi-planet systems, with up to five planets per system.

In 1999, ESO launched a call for opportunities to build a high resolution, extremely precise spectrograph for the ESO 3.6-metre telescope at La Silla, Chile. Michel Mayor, from the Geneva Observatory, led a consortium to build HARPS, which was installed in 2003 and was soon able to measure the back-and-forward motions of stars by detecting small changes in a stars radial velocity — as small as 3.5 km/hour, a steady walking pace.

Such a precision is crucial for the discovery of exoplanets and the radial velocity method, which detects small changes in the radial velocity of a star as it wobbles slightly under the gentle gravitational pull from an (unseen) exoplanet, has been most prolific method in the search for exoplanets.

In return for building the instrument, the HARPS consortium was granted 100 observing nights per year during a five-year period to carry out one of the most ambitious systematic searches for exoplanets so far implemented worldwide by repeatedly measuring the radial velocities of hundreds of stars that may harbour planetary systems.

The programme soon proved very successful. Using HARPS, Mayors team discovered — among others — in 2004, the first super-Earth (around µ Ara); in 2006, the trio of Neptunes around HD 69830; in 2007, Gliese 581d, the first super Earth in the habitable zone of a small star; and in 2009, the lightest exoplanet so far detected around a normal star, Gliese 581e. More recently, they found a potentially lava-covered world, with density similar to that of the Earths.

“These observations have given astronomers a great insight into the diversity of planetary systems and help us understand how they can form”, says team member Nuno Santos.

The HARPS consortium was very careful in their selection of targets, with several sub-programmes aimed at looking for planets around solar-like stars, low-mass dwarf stars, or stars with a lower metal content than the Sun. The number of exoplanets known around low-mass stars — so-called M dwarfs — has also dramatically increased, including a handful of super Earths and a few giant planets challenging planetary formation theory.

“By targeting M dwarfs and harnessing the precision of HARPS we have been able to search for exoplanets in the mass and temperature regime of super-Earths, some even close to or inside the habitable zone around the star”, says co-author Xavier Bonfils.

http://www.eso.org/public/outreach/press-rel/pr-2009/pr-39-09.html#

ESOcast is produced by ESO, the European Southern Observatory. ESO, the European Southern Observatory, is the pre-eminent intergovernmental science and technology organisation in astronomy designing, constructing and operating the worlds most advanced ground-based telescopes.

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Descubren 32 nuevos planetas fuera del Sistema Solar

Wednesday, October 21st, 2009, by Manuel and is filed under "Astrobiologia, Astrofisica, Astronomia, Ciencia, Cometas, Cosmologia, España, Fisica, Internacional, Science, Technology, Tecnologia, Universidad, Universo | , Agujeros negros, Astrobiologia, Astrofisica, Astronomia, Ciencia, Cosmologia, ESO, Exobiologia, Exoplanetas, Fisica, Instituto de Tecnología de California (EE UU), Investigacion, Observatorio de Ginebra, Science, Sistema Solar, Technology, Tecnologia, Tierra, Universo ". You can leave a response here, or send a Trackback from your own site.