Albedo maps of Comets P/Giacobini-Zinner and P/HalleyNear-simultaneous infrared and visual maps of P/Giacobini-Zinner (P/G-Z) and P/Halley are combined to create maps of the spatial variation of geometric albedo. Giacobini-Zinner shows a minimum in albedo near 0.07 with an increase of a factor of 2 over 30 arcsec. The lowest albedos are offset from the nucleus in the antisunward direction, coincident with a dust tail observed in the IR. The P/Halley albedos are higher than those for P/G-Z and range from 0.2 to 0.4, but the trend of darker albedo in the antisunward direction (along the tail) is the same. The albedo distribution is attributed to large, dark, fluffy grains confined to the orbital plane close to the nucleus. The high albedo values in P/Halley may be due to enhanced flux in the visual image because of the comet's very small phase angle.
Document ID
19870016486
Acquisition Source
Legacy CDMS
Document Type
Other
Authors
Hammel, H. B. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Storrs, A. D. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Cruikshank, D. P. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Telesco, C. M. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Decher, R. M. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Campins, H. (Planetary Science Inst. Tucson, Ariz., United States)
Date Acquired
September 5, 2013
Publication Date
December 1, 1986
Publication Information
Publication: ESA Proceedings of the 20th ESLAB Symposium on the Exploration of Halley's Comet. Volume 2: Dust and Nucleus