We have used the Keck I telescope to image at 11.7 and 17.9 μm the dust emission around ζ Leporis, a main-sequence A-type star at 21.5 pc from the Sun with an infrared excess. The excess is at most marginally resolved at 17.9 μm. The dust distance from the star is probably <=6 AU, although some dust may extend to 9 AU. The mass of observed dust is ~1022 g. Since the lifetime of dust particles is about 104 yr because of the Poynting-Robertson effect, we robustly estimate at least 4×1026 g must reside in parent bodies, which may be asteroids if the system is in a steady state and has an age of ~300 Myr. This mass is approximately 200 times that contained within the main asteroid belt in our solar system.
The Astrophysical Journal
- Pub Date:
- October 2001
- Stars: Circumstellar Matter;
- Stars: Planetary Systems;
- Stars: Individual: Bright Star Number: HR 1998;
- 12 pages, 3 figures, ApJL in press