Latest News

Is there anyone there? Alien hunters target two latest 'super Earths' found by Nasa

Is there anyone there? Alien hunters target two latest 'super Earths' found by Nasa, A star system containing two potentially habitable Earth-like planets is being targeted by scientists searching for extra-terrestrial intelligence.

In the coming months, astronomers will turn an array of radio telescope dishes towards Kepler-62, a star smaller and dimmer than the Sun about 1,000 light years away in the constellation Lyra.

A pair of so-called 'super-Earths' have been detected within the 'habitable zone' of the star, the orbital region where temperatures are just warm enough to allow bodies of surface water such as oceans and lakes.

The newly discovered planets named Kepler-62e and Kepler-62f, two of the five planets found around a far-off star, have been described as the most similar to Earth yet discovered


Nasa’s Kepler mission has discovered two new planetary systems that include three super-Earth-size planets in the 'habitable zone,' the range of distance from a star where the surface temperature of an orbiting planet might be suitable for liquid water.

The Kepler-62 system has five planets; 62b, 62c, 62d, 62e and 62f.

The Kepler-69 system has two planets; 69b and 69c. Kepler-62e, 62f and 69c are the super-Earth-size planets.

Two of the planets, named Kepler-62e and Kepler-62f, are rocky or made mostly of ice, and are believed to be the most likely to be Earth 'doubles'.

Although no-one knows what the planets are made of, they are believed to be rocky.

One, Kepler-62f, is thought to have a radius about 1.4 times greater than the Earth's. The other, Kepler-62e, is estimated to be 1.6 times larger.

The planets' parent star is around two billion years older than the Sun, raising the possibility of intelligent life more advanced than it is on Earth.

Welcome to Earth II... and III: Astronomers hail 'most similar' planets to ours ever found
Fresh Bigfoot mystery as police admit they are baffled by giant decomposed foot found in Massachusetts wood

Both will be priority targets in a new Search for Extra-Terrestrial Intelligence (Seti) programme focusing on habitable zone worlds.

They were discovered by Nasa's Kepler space telescope, which has so far detected almost 3,000 candidate planets outside the Solar System.

A fifth of these are believed to be 'super-Earths' between 1.25 and twice the size of the Earth.

Scientists at the Centre for Seti Research in the US are listening in for radio signals from the stars that display signs of technology and intelligence.

The search is being conducted from the Allen Telescope Array, a collection of small six-metre wide dishes in the Cascade Mountains of northern California.

The array, launched in 2007 with 42 dishes, will ultimately comprise 350 receivers operating round the clock.

'Our surveys improve on previous, generally narrow band Seti by covering the radio frequency range where Earth's atmosphere is most transparent, including many frequencies never before observed,' said Dr Gerry Harp, director of the Centre for Seti Research.

'We expect to complete a meaningful survey of these stars in less than one year. Be sure to check back soon.'

Dr Jon Jenkins, a member of the Seti Institute team based at Nasa's Ames Research Centre in California, whose Kepler-62 data is reported in the journal Science, said: "These discoveries move us farther down the road to discovering planets similar to Earth.

'While we don't know if Kepler-62e and f are rocky or whether they have liquid water pooling on their surfaces, their existence shows that the incidence of small worlds in the habitable zone of Sun-like stars is high.

Kepler-62 and the Solar System: The diagram compares the planets of the inner solar system to Kepler-62, a five-planet system about 1,200 light years from Earth in the constellation Lyra

'Thus we can look forward to the discovery and detailed characterisation of Earth's cousins in the years and decades to come by future missions and telescopes.'

The research suggests that both planets are solid and likely to have mostly dry rocky surfaces or be ocean-covered water worlds.

Three other planets close to the size of the Earth are also thought to be orbiting Kepler-62, but not in the habitable zone.Two planets found around a distant star have been described as the most similar to Earth yet discovered.

The planets in the newly found Kepler 62 system are made of rock and ice, and researchers believe they could contain water.

Kepler-62e and Kepler-62d are among five new planets found within the 'habitable' zone of a Sun-like star.

Kepler-62f, a super-Earth-size planet in the habitable zone of a star smaller and cooler than the sun, located about 1,200 light-years from Earth in the constellation Lyra. Kepler-62f orbits its host star every 267 days and is roughly 40 percent larger than Earth.

The artist's concept depicts Kepler-69c, a super-Earth-size planet in the habitable zone of a star like our sun, located about 2,700 light-years from Earth in the constellation Cygnus. Kepler-69c is 70 percent larger than the size of Earth, and is the smallest yet found to orbit in the habitable zone of a sun-like star

Artist's concept of Kepler-62e, located about 1,200 light years from Earth in the constellation Lyra. Kepler-62e orbits its host star every 122 days and is roughly 60 percent larger than Earth in size. Scientists do not know if Kepler-62e is a waterworld or if it has a solid surface

Announcing the discovery physicist Professor Justin Crepp said: 'From what we can tell, from their radius and orbital period, these are the most similar objects to Earth that we have found yet.'

They were identified by data from the Kepler mission launched in 2009 to identify extrasolar planets.

It has so far resulted in several dozen of some 3,000 'Kepler Objects of Interest' having been studied in detail but of those the 'five-planet system' is the most important.

Crepp noticed a faint dot near Kepler-62 a year ago, leading to months of detailed study to confirm the planet interpretation.

The discovery was made by astrophysicists at the University of Notre Dame.

The findings were published in Science magazine.

Researchers use fluctuations in the brightness of a star to identify the presence of a potential planet whose transit periodically dims the light of the star.

Crepp uses large ground-based telescopes to image the host star and analyzes the system to make sure other astronomical phenomena, such as nearby eclipsing binary stars, are not causing the fluctuation, a common 'false positive' encountered in the research.

'What really helped is that this star has five planets,' he said.

'You can mimic one planet with another event, but when you have five of them and they're all periodic, that helps to put the nail in the coffin.

'It's hard to make that kind of signature with anything else that you can dream up.'


The Kepler space observatory, named after the 17th century German astronomer Johannes Kepler, was launched on 7 March 2009 to survey a portion of the Milky Way for Earth-size planets that could harbour life.

The research team used data from Nasa's Kepler space telescope, which simultaneously and continuously measures the brightness of more than 150,000 stars every 30 minutes.

When a planet candidate transits, or passes, in front of the star from the spacecraft's vantage point, a percentage of light from the star is blocked.

This causes a dip in the brightness of the starlight that reveals the transiting planet's size relative to its star.

The size of the star must be known in order to measure the planet's size accurately.

To learn more about the properties of the stars, scientists examined sound waves generated by the boiling motion beneath the surface of the star.

They probe the interior structure of stars just as geologists use seismic waves generated by earthquakes to probe the interior structure of Earth.

The science is called asteroseismology.

The sound waves travel into the star and bring information back up to the surface.

The waves cause oscillations that Kepler observes as a rapid flickering of the star's brightness.

Like bells in a steeple, small stars ring at high tones while larger stars boom in lower tones.

The barely discernible, high-frequency oscillations in the brightness of small stars are the most difficult to measure.

This is why most objects previously subjected to asteroseismic analysis are larger than the sun.

No comments:

Post a Comment

Popular News Queries Designed by Copyright © 2014

Theme images by Bim. Powered by Blogger.
Published By Gooyaabi Templates