Capture the ‘Eye of Sauron’ in the Cosmos – La Vanguardia

Madrid. (Writing and agencies) -. The instrument SPHERE (search for exoplanets with spectro-polarimetry of high contrast, for its acronym in English), installed on the VLT (Very Large Telescope) at Paranal Observatory ESO (Chile), has already captured its first image. Although much like the Eye of Sauron - the Evil Lord of the Rings – which has grasped this new gadget is one of the best ones so far achieved dust ring around the nearby star HR 4796A .

image not only shows the ring with exceptional clarity, it also illustrates how SPHERE can remove the glare of the bright star at the center of the image. This new tool for locating and studying exoplanets combines several advanced techniques.

In the early days of observation has been confirmed that SPHERE provides improvement over previous instruments, providing striking images of dust disks around nearby stars and other objects observed.

SPHERE has been developed and built by a consortium of several European institutions, led by the Institute of Planetology and Astrophysics of Grenoble (France) in collaboration with ESO. This instrument is intended to revolutionize the detailed study of exoplanets and circumstellar disks .

In December 2013, SPHERE overcame his trials in Europe acceptance, after which he was sent to Paranal (Chile). Delicate reassembly was completed in May 2014 and now the instrument is installed on the VLT Telescope Unit 3. SPHERE is the last of the second generation instrument for the VLT (the first three were X-shooter, KMOS UXO).

SPHERE combines several advanced techniques in order to offer the highest contrast ever reached in obtaining direct images of planets, far beyond what could be achieved with the NACO instrument, which took the first direct image of an exoplanet.

To achieve this impressive performance, develop technologies needed SPHERE novel since its inception, particularly in the areas of adaptive optics, special detectors and components coronagraphy.

“SPHERE is a very complex instrument. Thanks to the hard work of many people who participated in its design, construction .! and installation, has already exceeded our expectations, it’s wonderful, “says Jean-Luc Beuzit, Institute of Planetology and Astrophysics of Grenoble (France) and principal investigator of SPHERE

Objective.: find exoplanets

The main objective of SPHERE is to find and characterize, by direct imaging, giant exoplanets orbiting nearby stars. This is an extremely difficult task, since these planets are much closer to their parent star and are much weaker.

In a normal image, even under the best conditions, the starlight hidden completely the faint glow of the planet. Therefore, the whole design of SPHERE is focused on achieving the highest contrast possible on a small piece of sky around the dazzling star.

The first of the three novel techniques used by SPHERE’s extreme adaptive optics , used to correct the effects of Earth’s atmosphere in order to make the images sharper and increase the contrast of exoplanets.

Second, a coronagraph is used to block light Star and further enhance contrast. Finally, a technique called differential image using the differences between the starlight and the planetary light in terms of color or bias is applied. These subtle differences can also be exploited to disclose the existence of a possible exoplanet that has not been previously detected. During the first test image several targets were observed using different modes of SPHERE.

After performing more extensive tests and observations of scientific verification, SPHERE will be available to the astronomical community throughout 2014. ” . This is just the beginning SPHERE is a unique and powerful tool and will undoubtedly give us many interesting surprises in the coming years http “., Jean-Luc Beuzit