Astronomy and Astrophysics – Astronomy
Scientific paper
Dec 2004
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004aj....128.3061j&link_type=abstract
The Astronomical Journal, Volume 128, Issue 6, pp. 3061-3069.
Astronomy and Astrophysics
Astronomy
17
Comets: General, Comets: Individual: Name: 2P/Encke, Techniques: Polarimetric
Scientific paper
We present high-resolution continuum imaging of comet 2P/Encke taken using the Hawaii Imaging Photo-Polarimeter (HIPPO). We measure the brightness, color, and polarization of the dust coma and nucleus at 22°, 93°, and 100° phase angles. At 22° phase angle and 1.4 AU heliocentric distance, the comet appears pointlike in narrowband continuum filters and is unpolarized. In contrast, at phase angles 93° and 100° and ~0.9 AU heliocentric distance the nucleus appears embedded in a fan-shaped coma that is highly polarized. We find that the nucleus is redder and less polarized than the adjacent coma, and that it is a highly phase-darkened object. The polarization of the coma increases with projected distance from the nucleus, suggesting a change in the mean scattering properties of the grains on a time-of-flight timescale of ~1 hr. We suggest that disaggregation of composite, porous grains in the heat of the Sun is a likely cause. The high coma polarization of this optically dust-poor comet violates a previously reported correlation between polarization and optical dust content. We briefly discuss the nature of this correlation.
No associations
LandOfFree
Looking through the HIPPO: Nucleus and Dust in Comet 2P/Encke does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Looking through the HIPPO: Nucleus and Dust in Comet 2P/Encke, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Looking through the HIPPO: Nucleus and Dust in Comet 2P/Encke will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1471383