Although not pass an extremely faint point of light, even the most powerful telescopes, a planet in another solar system, 300 light years away from Earth, was directly observed – announced on Monday the European South (ESO), the European organization for astronomy, it belongs to Portugal.
Despite already having discovered nearly 1,000 extrasolar planets – the first was in 1995, by the Swiss team of Michel Mayor and Didier Queloz – most of them were discovered using indirect methods. One is the method of radial velocities (detects small periodic oscillations in the motion of a star due to the presence of a planet around it), the other is the transits (detect tiny variations in the brightness of a star due to the passage through the front of a planet). So far, only 12 extra-solar planets, or exoplanets, have had their images captured directly, although they summarize the very faint pinpoints of light.
is now the case of a planet observed with Very Large Telescope (VLT), the European Southern Observatory in Chile has, on Mount Paranal. The planet appears as a faint but well-defined point, near a bright star in HD 95086. “It may be the planet with less mass to be directly observed outside the solar system,” the ESO.
“Get direct images of planets is an extremely large technical challenge that requires the most advanced instruments, whether in the ground or in space,” says Julien Rameau, Institute of Planetology and Astrophysics in Grenoble, which subscribes to the head Article about the discovery published in the journal Astrophysical Journal Letters . “Until now, few planets have been directly imaged, making each discovery an important milestone on the way to understand how giant planets form,” added Julien Rameau, a statement of the ESO.
To get directly the planet, the team used NACO – An adaptive optics instrument, which allows you to remove much of the disruption caused by the atmosphere and get sharp images – and thereafter sued the observations with a technique called “image differential “, which improves the contrast of brightness between the planet and the star.
The observations also showed that the fine point of the planet – called HD 95086 b – moving slowly with his star across the sky, suggesting that revolves around the star, located 300 light years from Earth. For the brightness of the planet, scientists estimate that has a mass equal to only four to five times the mass of Jupiter.
The planet is not close to the star, but at a distance equivalent to twice that separates Neptune from the Sun The star HD 95086 is very young, has only 10 to 17 million years and a little more mass than our Sun, who was born about 5000 million. As the star HD 95086 is so young astrophysicists think that the planet formed within the disk of gas and dust that surrounds it.
“Your current location raises questions about its formation process. Or increased by the inclusion of rock forming the solid core and then slowly accumulating gas atmosphere to form the atmosphere or heavy began to form from a cluster of gases arising from the disk due to gravitational instabilities “explains another team member, Anne-Marie Lagrange, quoted in the statement. “Interaction with the disk of the planet or other planets may also have shifted the planet’s birthplace.”
Using the luminosity of the star, the team also estimated the surface temperature of the planet: will have around 700 degrees Celsius. “This is cold enough for there to be possibly water vapor and methane in its atmosphere.”
Now water is an essential element to life – and this discovery, from another planet, somewhere in the vastness of the universe, teeming with life, is the great dream of many people.
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