WISE/NEOWISE PRELIMINARY ANALYSIS AND HIGHLIGHTS OF THE 67P/CHURYUMOV-GERASIMENKO NEAR NUCLEUS ENVIRONS

Journal Article · Wed Oct 10 00:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/758/1/18· OSTI ID:22092120

Bauer, James M.; Kramer, Emily; Mainzer, A. K.; Stevenson, Rachel; Masiero, Joseph R.; Weissman, Paul R. ^[1]; Grav, Tommy ^[2]; Walker, Russell G. ^[3]; Fernandez, Yan R. ^[4]; Meech, Karen J. ^[5]; Lisse, Carey M. ^[6]; Cutri, Roc M.; Dailey, John W.; Masci, Frank J.; Pearman, George ^[7]; Tholen, David J. ^[8]

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1. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, MS 183-401, Pasadena, CA 91109 (United States)
2. Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395 (United States)
3. Monterey Institute for Research in Astronomy, 200 Eighth Street, Marina, CA 93933 (United States)
4. Department of Physics, University of Central Florida, 4000 Central Florida Boulevard, P.S. Building, Orlando, FL 32816-2385 (United States)
5. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Manoa, HI 96822 (United States)
6. Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723-6099 (United States)
7. Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)
8. NASA Astrobiology Institute, University of Hawaii, Manoa, HI 96822 (United States)

On 2010 January 18-19 and June 28-29, the Wide-field Infrared Survey Explorer (WISE) spacecraft imaged the Rosetta mission target, comet 67P/Churyumov-Gerasimenko. We present a preliminary analysis of the images, which provide a characterization of the dust environment at heliocentric distances similar to those planned for the initial spacecraft encounter, but on the outbound leg of its orbit rather than the inbound. Broadband photometry yields low levels of CO{sub 2} production at a comet heliocentric distance of 3.32 AU and no detectable production at 4.18 AU. We find that at these heliocentric distances, large dust grains with mean grain diameters on the order of a millimeter or greater dominate the coma and evolve to populate the tail. This is further supported by broadband photometry centered on the nucleus, which yield an estimated differential dust particle size distribution with a power-law relation that is considerably shallower than average. We set a 3{sigma} upper limit constraint on the albedo of the large-grain dust at {<=}0.12. Our best estimate of the nucleus radius (1.82 {+-} 0.20 km) and albedo (0.04 {+-} 0.01) are in agreement with measurements previously reported in the literature.

• OSTI ID: 22092120
• Journal Information: Astrophysical Journal, Vol. 758, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ALBEDO
ASTRONOMY
ASTROPHYSICS
CARBON DIOXIDE
COMETS
DISTANCE
DUSTS
GRAIN SIZE
IMAGES
INFRARED SURVEYS
ORBITS
PARTICLE SIZE
PHOTOMETRY