The Birth of a Planetary System
The Hubble Space Telescope has discovered anomalies in the disk of dust surrounding the star beta Pictoris that may be caused by one or more planets. There is also evidence of a brown dwarf star near the young planetary system. Two new visible-light images from the Hubble Space Telescope point to the edge of the dust disk around the star beta Pictoris. They are powerful clues about the existence of planets and possibly also the gravitational pull of a neighboring brown dwarf or a passing star. Both views reveal disk deformations that could be caused by the gravitational pull of one or more accompanying celestial bodies. Since the discovery of the disc of dust around beta Pictoris in 1984, it has been assumed that a planetary system that is still evolving could exist there. Among the planetary system candidates, it is one of the closest to Earth.
The full extent of the dust disk measures about 225 billion kilometers (1500 astronomical units) from edge to edge. An unusual bulge at the top right of the disk (southwest side) shows that dust has been drawn into the areas above the dense disk plane, and to a greater extent than is seen on the left side. A possible reason for this would be the gravitational pull of an invisible companion with a mass less than that of stars. However, this body would be too far away from the central star for a planet. Another reason could be the gravitational pull of a passing star.
A detailed close-up of the inner disc region shows a distortion in the disc. Unlike the first images taken in 1995, the new images bring viewers closer to the star than ever before, some 2.25 billion kilometers (15 astronomical units). These new details support the thesis of one or more planets orbiting the star.
The false color images show gradations in the brightness of the pane. Since the dust does not glow itself, but only reflects the light of the stars, it shines less brightly the greater the distance to the central star. In both images, the glaring central star is obscured by a black band. This divides the view of the dust disk into left (east) and right (west) components. Because the disk is tilted almost edge-to-earth, the images show a sharp, bright, and straight ridge that extends the full length of the disk.
The Heidelberger Verlag Spektrum der Wissenschaft is the operator of this portal. Its online and print magazines, including "Spektrum der Wissenschaft", "Gehirn&Geist" and "Spektrum – Die Woche", report on current research findings.
