Astronomers discover potentially habitable super-Earth

This planet is the new best candidate to support liquid water and, perhaps, life as we know it. Co-discoverer Guillem Anglada-Escude Astronomers have discovered a potentially habitable super-Earth planet orbiting a nearby star, making it one of the best candidates to support life. The newly found planet, called GJ 667Cc, has a mass 4.5 times that of Earth and orbits its host star every 28 days.

The research team used public data from the European Southern Observatory and analyzed it with great precision. The star, GJ 667C, is a member of a triple star system and is different from our Sun as it lacks in metallic elements. GJ 667C is a red dwarf and is located in the constellation Scorpio about 22 light years away from Earth.

The super-Earth planet receives 90 percent of the light that our planet receives but the planet is expected to absorb about the same amount of energy that Earth absorbs as more of the star's light is infrared.

The level of energy and light absorption makes it possible for the planet to have liquid water and more balanced surface temperature.

“This planet is the new best candidate to support liquid water and, perhaps, life as we know it,” said co-discoverer Guillem Anglada-Escude.

“If it has an atmosphere, it's probably reddish all the time, because the star is really red,” Anglada-Escude added.

The team notes that the system might also contain a gas-giant planet and an additional super-Earth.

A detailed description of the new super-Earth will be published in an upcoming issue of the Astrophysical Journal Letters.

Meanwhile,NASA has confirmed the discovery of Kepler-22b, the first planet in the “habitable zone,” where liquid water could exist on a planet's surface.

The Kepler spacecraft discovered Kepler-22b in the habitable zone, 600 light-years away from Earth, NASA said recently.

The discovery of Kepler-22b brings scientists one step closer to finding a planet that could possibly harbour life.

“This is a major milestone on the road to finding Earth's twin,” Kepler programme scientist Douglas Hudgins said in a statement. “Kepler's results continue to demonstrate the importance of NASA's science missions, which aim to answer some of the biggest questions about our place in the universe.”

Kepler-22b has several Earth-like characteristics. Its temperature is around 72 degrees Fahrenheit and its radius is 2.4 times Earth's. The planet completely orbits its star, which is similar to our sun, every 290 days, just 75 days shy of an Earth year.

NASA says scientists do not yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets.

Of the 54 habitable zone planet candidates reported in February 2011, Kepler-22b is the first to be confirmed.

Meanwhile, Scientists at the California Institute of Technology (Caltech) have discovered 18 new planets orbiting stars bigger than our sun.

Astronomers used twin telescopes at the Keck Observatory in Hawaii, looking for slight wobbles caused by the gravitational tug of orbiting planets.

The newly found planets with masses similar to Jupiter's, provide an invaluable population of planetary systems for understanding the formation and evolution of planets and our own solar system, Science Daily reported.

“It's the largest single announcement of planets in orbit around stars more massive than the sun, aside from the discoveries made by the Kepler mission,” said John Johnson as first author on the paper of The Astrophysical Journal Supplement Series.

Researchers believe the findings also lend further support to the theory that planets grow from seed particles that accumulate gas and dust in a disk surrounding a newborn star.

According to this theory, tiny particles start to form a solid mass, eventually snowballing into a planet. If this is the true sequence of events, the characteristics of the resulting planetary system will depend on the mass of the star.

The theory means that a huger star would present a bigger disk, which in turn would mean more material to produce a greater number of giant planets. The new batch of planets has another interesting pattern. Their orbits are mainly circular, while planets around sunlike stars cover a wide range of circular to elliptical paths.

Johnson and his team are now studying to find an explanation for the pattern.

Meanwhile, astronomers have spotted the first cannibal stars ever discovered in the heart of our Milky Way galaxy, using NASA's Hubble Space Telescope.

Also known as blue stragglers, cannibal stars drain life away from other stars and seem to remain younger than the stars they destroy. The so-called vampire stars seem to move slowly toward neighbouring stars to suck in gas from them. That is why they look hotter, younger and bluer.

According to National Geographic News, cannibal stars are routinely found in dense star clusters, where stars have many chances to feed off each other.

The new discovery, however, has unveiled blue stragglers in a dense region of stars and gas surrounding the Milky Way's centre known as the galactic bulge.

“For a long time, it was suspected there were blue stragglers in the bulge, but no one knew how many there might be,” said Will Clarkson, an astronomer at Indiana University Bloomington and the University of California, Los Angeles.

“At long last, we've shown they're there.”

Using Hubble to look at 180,000 stars in and near the bulge, astronomers found 42 unusually blue stars that seemed much younger than the other stars.

Researchers say 18 to 37 of these 42 stars are probably real blue stragglers that are about 10 billion to 11 billion years old. The rest might be genuinely young stars in the bulge, or stars not actually in the bulge. Scientists also consider the possibility that the blue stragglers of the galactic bulge might have been formed by ripping hydrogen off their companion stars.

“There's still a lot we don't know about the details of how blue stragglers form,” Clarkson said.

“Finding them in the bulge provides another set of constraints that can help refine models of their formation.” Press TV