Although we’ve been able to see disks of debris around other stars, astronomers have yet to resolve one around a Sun-like star. But that may have just changed: HD 107146, a G2 star some 93 light years away, is the subject of a paper now available at the ArXiv site.
Working with the Hubble Space Telescope and its ACS coronagraph, a team of astronomers led by Johns Hopkins’ David Ardila has directly viewed such a disk. “A Resolved Debris Disk around the G2V star HD 107146” is slated to appear in Astrophysical Journal Letters, but is now online here (PDF warning).
From the paper:
The presence of dusty disks around main-sequence stars serves as a marker for the existence of planetesimals. Without collisions among planetesimals, or their evaporation, the dust would not be replenished, and it would have disappeared from the system long ago. Thus, debris disks indicate that the planet-formation process is occurring, or has occurred. In particular, the study of disks around low-mass stars illuminates the planet-formation process in the relatively low-radiation environments analogous to the solar system. Resolved images of these systems help to constrain their physical and geometrical properties. Scattered-light images sample the whole disk regardless of its temperature and this, coupled with the fact that optical and near-infrared detectors have higher angular resolution than far-infrared and submillimeter ones, allows for a rich understanding of the systems.
But Ardila and his colleagues argue that the dust disk around HD 107146 is not analagous to our own early Solar System, noting that it is larger and wider than the Kuiper Belt and contains significantly more dust. “We believe therefore,” write the team, “that HD 107146 is unlikely to evolve into a system like our own.”
Earlier in 2004, Ardila and other scientists working on planetary disks presented their findings on the debris around HD 141569A, a triple-star system 332 light years from the Sun. An abstract from their presentation at the AAS meeting in January, 2004 is available here.
