The Discovery of Halley-sized Kuiper Belt Objects Using the Hubble Space Telescope
We report the statistical detection (at the >99% confidence level) of a population of 28th magnitude objects exhibiting proper motions of ≈1" hr-1 at quadrature in deep Hubble Space Telescope (HST)/WFPC2 images. The drift directions imply a preponderance of objects on prograde orbits concentrated near the ecliptic plane. We interpret this as the detection of objects which reside in the Kuiper belt near or beyond the orbit of Neptune, comparable in size to comet 1P/Halley (radii ∼10 km for an albedo of 4%). Our observations imply a population of ∼2.5 × 104 objects deg-2 with V <28.6. This must be viewed as a lower limit until our search of parameter space is complete. Our observations imply that there are >2 × 108 objects of this size in the Kuiper belt with inclinations <12° and within ∼40 AU of the Sun.
The Astrophysical Journal
- Pub Date:
- December 1995
- COMETS: GENERAL;
- SOLAR SYSTEM: GENERAL;
- 11 pages of text plus three figures attached with epsf macros, uses AASTeX macros (aaspp), to appear in 10 December 1995 Astrophysical Journal