NASA astronomers discovered the smallest planet

Astronomers discovered the smallest planet outside our solar system. This is the first that is certainly rocky like Earth. Measurements of extraordinary precision-called Kepler showed that 10b is 1.4 times the diameter of Earth and a mass 4.6 times greater than he. However, because it orbits very close to its star, the exoplanet could not support life. The discovery has been hailed as "one of the deepest in the history of mankind."

The result was announced at the 217th annual meeting of the American Astronomical Society in Seattle, by the Kepler telescope team space agency NASA. The Kepler is designed to search for signs of distant planets, first sighted the exoplanet at a distance of 560 light years, along with hundreds of other candidate planets.

Technique

The Kepler space telescope uses a technique known as transiting in English, which is the search for planets that pass between the sun and Earth guest. This report will be considered as one of the most profound scientific discoveries in the history of mankind Geoffrey Marcy, University of California, Berkeley.

A small fraction of the star's light is blocked periodically, giving an indication that the star has a planet orbiting. The radius of exoplanet correlates with the exact amount of light that is blocked when passing.

The review of the measures, this time by a telescope at the Keck Observatory in Hawaii, confirmed the discovery of Kepler 10b, after measuring how the planet moves away from one side to another of its parent star as it continues its orbit. These measurements also confirmed that the star has approximately 8,000 million years, a sort of grandfather among the stars of its type.

Basically, this means that the sun is free of optical and magnetic activities, which have introduced some uncertainty in the calculations of previous candidates to rocky exoplanets like Corot-7b, whose discovery was announced in early 2009.

Constantly expanding

The cosmic dance causes small changes in the color of the starlight that is measured by telescopes. However, completing the set of measurements Kepler team was the use of asteroseismology, a study of distant stars that is similar to the analysis of earthquakes on Earth. The oscillation occurs within a star-like in the interior of our planet, affecting the frequencies of light emitted by the star in a telling sign of its size.

We have determined the characteristics of this planet with a precision so fantastic that we can say without doubt that this is a rocky world in which one could stand Natalie Batalha, San Jose State University. With data as the mass of the parent star, the details of the mutual dance of the planet and the star, and the radius of the exoplanet can calculate the density of the planet.

"All our best capabilities have come together to form an image of Kepler 10b," said Natalie Batalha, a professor of astrophysics at San Jose State University, who helps run the Kepler science mission for NASA. Batalha told the BBC that the only result was a widening field of exoplanet discoveries, in which heavenly bodies are getting smaller, while improving experimental methods. "We have determined the characteristics of this planet with a precision so fantastic that we can say without doubt that this is a rocky world in which one could stand," he added.

Are we alone?

The Kepler 10b is very close to its sun, while its daytime temperature exceeds 1300 ° C. Therefore, the exoplanet is not a reasonable candidate for harboring life. However, as explained Professor Batalha, the finding is an important step for the Kepler mission. An artist's impression shows how the face would look Kepler 10b watching his star.

"We want to know whether we are alone in the galaxy and this discovery is a link in the chain to reach that goal," he said. "First we have to know if planets that could potentially harbor life are common, something we do not know. That's what Kepler aims," ​​he added.

The pioneer of the "hunt" for exoplanets Geoffrey Marcy of the University of California at Berkeley, said the Kepler 10b is "a global link lost".

"It is a bridge between the gas giant planets we've been finding and the Earth itself, a transition from what I have been finding and what we hope to find." "This report will be considered as one of the most profound scientific discoveries in human history," he concluded.