Astronomers from the University of Keele have announced the discovery of three
new planets. These planets, orbiting stars other than the sun, were discovered
by the UK’s leading planet-search team, a consortium of universities
known as the Wide Angle Search for Planets, or WASP project.
All three of these extra-solar planets were detected when they were seen to pass in front of, or transit, their host star. Studying such planets allows scientists to investigate how planets form. Dr Coel Hellier, of Keele University, comments “When we see a transit we can deduce the size and mass of the planet and also what it is made of, so we can use these planets to study how solar systems evolve”.
Keele University's Astrophysics Group operates a robotic observatory called WASP-South, located in South Africa, specially designed to look for transiting planets. Dr Hellier says “We built this observatory to look for planets and now we have found some. We call these planets after our project, and WASP-4 and WASP-5 are now the two brightest transiting planets known in the whole Southern sky''. Team member David Wilson comments “The observatory consists of eight wide-field cameras which image millions of stars simultaneously. We need to observe this many to stand any chance of detecting the very rare transits of a planet passing in-front of a star”.
Exoplanet expert Dr. Pierre Maxted comments “The planets are known as ‘hot-Jupiters’ as they are similar to Jupiter but are so close to their parent star that they orbit it in less than two days. This means that these planets have a surface temperature of nearly 2000°C and so are unlikely to host life. But finding these planets is important as these stars could also host much smaller planets similar to Earth, although detecting these worlds will be much more difficult”.
The planets orbit around stars similar to our Sun that are located at a distance of 850 light-years away from the Earth. Two are in the constellation of Phoenix visible only from the Southern hemisphere, while the third is in the Northern constellation of Lyra. All three stars are too faint to be seen with the naked eye, but are easily detectable with a small telescope.
More information on the WASP planets can be found at www.superwasp.org/wasp_planets.htm
A live feed from the WASP-South observatory can be seen at: http://wasp.astro.keele.ac.uk/live/
Notes for Editors:
The following images may be used to illustrate this story:
http://www.superwasp.org/press_release2/sws.jpg (Credit: David Wilson)
Caption: The WASP-South observatory opens for dusk.
http://www.superwasp.org/press_release2/8cams.jpg (Credit: David Anderson)
Caption: WASP-South's eight cameras ready to search for planet transits.
http://www.superwasp.org/press_release2/millenium.jpg
Caption: An artist's impression of an extra-solar planet.
http://www.superwasp.org/press_release2/keele_transit.gif (Credit: Iain McDonald)
Caption: A transit of WASP-3 recorded by the Keele Observatory, showing
the dip in brightness when the planet transits the star.
Transit: A transit occurs when a planet passes in front of its star, blocking some light and causing a small dip in the brightness of the star. The WASP cameras monitor millions of stars, looking for these dips.
Extrasolar planet: a planet around another star, rather than our Sun.
Exoplanet: an abbreviation of “extrasolar planet”
WASP cameras: Arrays of wide-field cameras monitoring millions of stars for transit events. One array of 8 cameras is sited in the Southern hemisphere in South Africa, and is operated by Keele University. The other array of 8 cameras is sited in the Northern hemisphere, on La Palma in the Canary Islands, and is operated by Queen's University Belfast. Each camera consists of a 200 mm f/1.8 lens backed by a high-specification 2048x2048 CCD chip.
WASP project: The acronym stands for “Wide Angle Search for Planets”, a consortium of UK universities searching for transiting exoplanets.
WASP-3, WASP-4, WASP-5. The names given to planets discovered by the WASP project.
WASP-1 and WASP-2 were discovered last year.
Contacts:
Dr Coel Hellier, Keele University Tel: 01782 584243
Dr Pierre Maxted, Keele University Tel: 01782 583457
David Wilson, Keele University Tel: 01782 583530
