New observations with the Subaru telescope in Hawaii, so far most detailed images of the protoplanetary disks of two young stars have delivered. For the first time, structures of about the same size as our own solar system visible rings and gaps in the disk associated with the formation of giant planets. The observations are part of a systematic survey with the instrument HiCIAO, a high-contrast camera, which specializes in the search for exoplanets and protoplanetary disks.planetary systems like our solar system are by-products of star formation. They form when the gravitational force of the newborn star, gas and dust from the surrounding area into a dense, flattened disc collects, which surrounds the star. Matter clumps in the disk draw more and more gas and dust in itself and so millions of years to the objects we call planets. In recent years the study of such "protoplanetary discs" has made significant progress - the one in (mostly indirect) observations, and the theoretical understanding and simulation of such objects. Two new observations have added to the overall picture provided important new details and pictures of structures that had never been imaged directly.
target of the first study was the star LKCA 15, of the approximately 450 light-years from Earth in the constellation Taurus is located. With an age of only a few million years LKCA 15 is a very young star (compared to our sun is about one thousand times as old). From previous observations of the infrared spectrum of the system, as well as the millimeter radiation it emits, scientists had developed it in the center of the protoplanetary disk is a large, mostly matter-free recess. The new images show stellar light reflected from the disc surface so is that the sharp edge of this recess is directly visible for the first time. Interestingly, the elliptical shape of the hole is not centered around the star, but something shifted.
The most likely explanation for the gap in the disk of LKCA '15 - and especially for the asymmetry - is that there several Planet circling that are currently developed only from the disk material and says now capture the gas and dust along its orbit, "Christian Thalmann, who led the study, at that time as a research associate at the Max-Planck-Institute for Astronomy (MPIA). The recess is so large that the orbits of all planets in our solar system easily they would take. Since it seems reasonable to speculate that at LKCA 15 in this issue our own solar system makes a similar planetary system. "The planets themselves were" not yet demonstrated, it Thalmann. "But that could soon change."
The second study, conducted by Jun Hashimoto (National Observatory Japan), was dedicated to the star AB Aur in the constellation Auriga, 470 light years from Earth. This star is even younger: only about one million years old. The new observations showed for the first time structures in the cosmic scale is comparatively small, that is not greater than our own solar system (compared with a distance of 470 light years, our solar system the same apparent size as a one-euro coin, which is from more than 10 km distance considered). The observations show interlocking rings of gas and dust that are tilted with respect to the equatorial plane of the system and the material again not arranged symmetrically around the star is - both features suggest the presence of at least one very massive planets.
The observations were made with the HiCIAO each instrument at the 8.2-meter Subaru telescope. Disks and planets in the vicinity of stars to make the observation technology the highest standards, as these faint objects are illuminated by the stars simply. HiCIAO succeed such observations by the instrument compensates for the disturbing influence of Earth's atmosphere a large extent, on the other hand most of the starlight fades out mechanically.
via Information Wissenschaft
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