A fifth planet has been discovered around a nearby star, making it the largest planetary system known outside our own. The planet appears to be a gas giant like Saturn, but scientists say any large moons it may have could potentially host life, since the planet lies in the "habitable" zone around its star, where liquid water can exist. The planet was discovered around a star called 55 Cancri that is about 41 light years away from Earth and is slightly cooler and dimmer than our own Sun.
This wide-angle photograph of the night sky shows the location of 55 Cancri, a star where astronomers have found a record-breaking five planets. Expand (713kb, 1247 x 859) | Image, no labels (807Kb, 1280 x 1230)
A team of American astronomers announced today (Tuesday, Nov. 6) the discovery of a record-breaking fifth planet around the nearby star 55 Cancri, making it the only star aside from the sun known to have five planets. The discovery comes after 19 years of observations of 55 Cancri and represents a milestone for the California and Carnegie Planet Search team, which this year celebrates the 20th anniversary of its first attempts to find extrasolar planets by analysing the wobbles they cause in their host star.
Astronomers have announced the discovery of a fifth planet circling 55 Cancri, a star beyond our solar system. The star now holds the record for number of confirmed extrasolar planets orbiting in a planetary system. 55 Cancri is located 41 light-years away in the constellation Cancer and has nearly the same mass and age as our sun. It is easily visible with binoculars. Researchers discovered the fifth planet using the Doppler technique, in which a planet's gravitational tug is detected by the wobble it produces in the parent star. NASA and the National Science Foundation funded the research. The newly discovered planet weighs about 45 times the mass of Earth and may be similar to Saturn in its composition and appearance. The planet is the fourth from 55 Cancri and completes one orbit every 260 days. Its location places the planet in the "habitable zone," a band around the star where the temperature would permit liquid water to pool on solid surfaces. The distance from its star is approximately 116.7 million kilometres, slightly closer than Earth to our sun, but it orbits a star that is slightly fainter.
Astronomers searching for signs of a Solar System like our own said on Thursday that they had found a planet very similar to Jupiter orbiting a star resembling the Sun, 90 light years away.
"This is the closest we have got to a real Solar System-like planet and advances our search for systems that are even more like our own" - UK team leader Hugh Jones of Liverpool John Moores University.
With a mass twice that of gas giant Jupiter, the planet circles star HD70642 in the constellation Puppis once every six years.
Three giant planets that sizzle as they circle their suns have been discovered in a faraway corner of the galaxy by a team of British astronomers. The alien worlds are believed to be among the hottest planets ever spotted, with surface temperatures rising to more than 2500C as they pass their parent stars.
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 UKs 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.
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 - Dr Coel Hellier, of Keele University
Keele University's Astrophysics Group operates a robotic observatory called WASP-South, located in South Africa, specially designed to look for transiting planets.
The planets are all similar in size and composition to Jupiter, but orbit their stars so closely that their year is shorter than two days. They are unlikely to harbour life because of surface temperatures in excess of 2,000C (3,632F). Two planets named Wasp4 and Wasp5 were identified using cameras in South Africa. Wasp3 was picked up by a camera in the Canary Islands. The team has also found two other exosolar planets in the northern hemisphere. Coel Hellier, of Keele University, who led the study, said of Wasp4 and Wasp5: These two are now the brightest transiting planets in the southern hemisphere.
Britain's leading team of planet-hunters says it has found three new alien worlds that lie beyond our solar system, boosting confidence that Earth-like worlds are waiting to be discovered. The discovery of the planets will be announced by the Wide Area Search for Planets (WASP) project this week at an international conference in Suzhou, China, and have been called WASP-3, WASP-4 and WASP-5. The WASP project is the most ambitious in the world designed to discover large planets and relies on "super cameras" that monitor millions of stars in the sky. Prof Andrew Cameron, of St Andrews University says the new finds add to two alien planets found by the team last year:
"All three planets are similar to Jupiter, but are orbiting their stars so closely that their 'year' lasts less than two days. These are among the shortest orbital periods yet discovered".
Three new planets have been discovered by a team of astronomers, including a researcher from St Andrews University. Powerful cameras in South Africa and the Canary islands found the planets, thought to be the size of Jupiter. They have been named WASP-3, WASP-4 and WASP-5. The astronomy team which made the find said the planets were in our galaxy but not orbiting the Sun.