tblaxland
O-F Administrator
Direct Images of Disks Unravel Mystery of Planet Formation
One of the images is of the disk of the very young star AB Aur in the constellation Auriga. The star is only about one million years old and is surrounded by its protoplanetary disk, a structure of gas and dust from which planets are likely to form. The image displays high spatial resolution as well as high contrast within the disk near its central star; it reveals, for the first time, the fine structures of a disk orbiting closer to its star than Neptune's distance from the Sun in our solar system. AB Aur's disk has double rings that are tilted from the equatorial plane; a void of material between the rings; and a center that does not coincide with the position of the star. These irregularities suggest that at least one giant planet is affecting the features of the disk.
Near-infrared (1.6 micron) images of AB Aur. The top panels compare images taken by HiCIAO and CIAO. Both images have a field of view of 7.5" by 7.5". Top left: Image taken by HiCIAO using a coronagraphic occulting mask with a 0.3" diameter. Top right: Image taken by CIAO using a software mask with a 1.7" diameter. The bottom panels show close-up views of the inner part of AB Aur's disk. Both images have a field of view of 2.0" by 2.0". Bottom left: Image has a coronagraphic occulting mask with a 0.3" diameter. Bottom right: Image includes labels of its prominent features. The central position (0, 0) refers to the location of the star. Ellipsoids in dashed lines show the outer and inner rings. The solid ellipsoid indicates the wide gap between the rings. The "+" shows where the star is. The filled circle is the center of the outer ring. For this object, 1" (one arc second) corresponds to 144 AU in real scale (144 times the distance between Earth and Sun).
