COROT's new find orbits Sun-like star

Jul 24, 2008
The lightcurve of the parent star of the newly-found exoplanet, COROT-exo-4b. COROT-exo-4b is an exoplanet of about the same size as Jupiter. It takes 9.2 days to orbit its star, the longest period for any transiting exoplanet ever found. Credits: COROT exo-team

A team of European scientists working with COROT have discovered an exoplanet orbiting a star slightly more massive than the Sun. After just 555 days in orbit, the mission has now observed more than 50 000 stars and is adding significantly to our knowledge of the fundamental workings of stars.

The latest discovery, COROT-exo-4b is an exoplanet of about the same size as Jupiter. It takes 9.2 days to orbit its star, the longest period for any transiting exoplanet ever found.

The team has found that the star, which is slightly larger than our Sun, is rotating at the same pace as the planet's period of revolution. This is quite a surprise for the team, as the planet is thought to be too low in mass and too distant from its star, for the star to have any major influence on its rotation.

Launched in December 2006, COROT is the first space-based mission designed to search for exoplanets. Located outside Earth's atmosphere, the satellite is designed to detect rocky exoplanets almost as small as Earth. The satellite uses transits, the tiny dips in the light output from a star when a planet passes in front of it, to detect and study planets. This is followed up by extensive ground-based observations.

Monitoring COROT-exo-4b continuously over several months, the team tracked variations in its brightness between transits. They derived its period of rotation by monitoring dark spots on its surface that rotated in and out of view.


It is not known whether COROT-exo-4b and its star have always been rotating in sync since their formation about 1000 million years ago, or if the star’s rotation synchronized later. Studying such systems with COROT will help scientists gain valuable insight into star-planet interactions.

This is the first transiting exoplanet found with such a peculiar combination of mass and period of rotation. There is surely something special about how it formed and evolved.

This discovery is being presented today at the Cool Stars 15 meeting at St Andrews University.

The ground-based follow-up of the detection of COROT-exo-4b was carried out with the cross-dispersed echelle spectrograph, SOPHIE, on the 1.8-m telescope at the Observatoire de Haute Provence (France), the High Accuracy Radial velocity Planet Searcher, HARPS on the 3.6-m telescope at La Silla observatory (Chile) and the cross-dispersed echelle spectrograph, UVES on the 8.2-m Very Large Telescope at Paranal (Chile), the 1-m telescope at the Wise Observatory in Israel, the 1-m Euler telescope at La Silla, and the 3.6-m Canada-France-Hawaii telescope.

COROT is a CNES project with ESA participation. The other major partners in this mission are Austria, Belgium, Brazil, Germany and Spain.

Provided by ESA

Explore further: Comet Jacques makes a 'questionable' appearance

add to favorites email to friend print save as pdf

Related Stories

Lives and deaths of sibling stars

Jul 23, 2014

This beautiful star cluster, NGC 3293, is found 8000 light-years from Earth in the constellation of Carina (The Keel). This cluster was first spotted by the French astronomer Nicolas-Louis de Lacaille in ...

Is our solar system weird?

Jul 18, 2014

Is our Solar System normal? Or is it weird? How does the Solar System fit within the strange star systems we've discovered in the Milky Way so far?

The Sloan Digital Sky Survey expands its reach

Jul 16, 2014

The Sloan Digital Sky Survey (SDSS) has launched a major program of three new surveys, adding novel capabilities to expand its census of the Universe into regions it had been unable to explore before.

Surrey NanoSystems has "super black" material

Jul 15, 2014

(Phys.org) —A British company says it has scored a breakthrough in the world's darkest material. Surrey NanoSystems describes its development as not just a black material but super-black. They are calling ...

NASA mission to reap bonanza of earth-sized planets

Jul 15, 2014

Set to launch in 2017, NASA's Transiting Exoplanet Survey Satellite (TESS) will monitor more than half a million stars over its two-year mission, with a focus on the smallest, brightest stellar objects.

Recommended for you

Comet Jacques makes a 'questionable' appearance

2 hours ago

What an awesome photo! Italian amateur astronomer Rolando Ligustri nailed it earlier today using a remote telescope in New Mexico and wide-field 4-inch (106 mm) refractor. Currently the brightest comet in ...

Image: Our flocculent neighbour, the spiral galaxy M33

2 hours ago

The spiral galaxy M33, also known as the Triangulum Galaxy, is one of our closest cosmic neighbours, just three million light-years away. Home to some forty billion stars, it is the third largest in the ...

Image: Chandra's view of the Tycho Supernova remnant

Jul 25, 2014

More than four centuries after Danish astronomer Tycho Brahe first observed the supernova that bears his name, the supernova remnant it created is now a bright source of X-rays. The supersonic expansion of ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

Mercury_01
not rated yet Jul 25, 2008
Why is it that all these new planets have such extremely short periods? It boggles my mind that a jupiter sized planet orbits in less than 10 days.
Modernmystic
not rated yet Jul 31, 2008
This is what I like to see coming from the space program. New data that really helps us with our understanding of how the rest of the galaxy/universe works. These are the fundamental questions I like to see progress towards:

1.How unique are we here in our little solar system?

2.How many planets out there are likely to have life?

3.How many of these in fact do have life, and is it the kind that can just slither around or might they say hello someday?