Debiasing the NEOWISE Cryogenic Mission Comet Populations
| Autor: | Tommy Grav, John W. Dailey, James M. Bauer, Phillip Krings, Yanga R. Fernandez, Edward L. Wright, Roc M. Cutri, R. Stevenson, Timothy Spahr, Russell G. Walker, Amy Mainzer, Carrie R. Nugent, Joshua Rosser, Kinjal Ruecker, Karen J. Meech, Carey M. Lisse, Joseph R. Masiero, E. A. Kramer |
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| Rok vydání: | 2017 |
| Předmět: |
Physics
education.field_of_study 010504 meteorology & atmospheric sciences Comet Population Astronomy Astronomy and Astrophysics Astrophysics 01 natural sciences Space and Planetary Science 0103 physical sciences Range (statistics) education 010303 astronomy & astrophysics 0105 earth and related environmental sciences |
| Zdroj: | The Astronomical Journal. 154:53 |
| ISSN: | 1538-3881 |
| DOI: | 10.3847/1538-3881/aa72df |
| Popis: | We use NEOWISE data from the four-band and three-band cryogenic phases of the Wide-field Infrared Survey Explorer mission to constrain size distributions of the comet populations and debias measurements of the short- and long-period comet (LPC) populations. We find that the fit to the debiased LPC population yields a cumulative size−frequency distribution (SFD) power-law slope (β) of −1.0 ± 0.1, while the debiased Jupiter-family comet (JFC) SFD has a steeper slope with β = −2.3 ± 0.2. The JFCs in our debiased sample yielded a mean nucleus size of 1.3 km in diameter, while the LPCs' mean size is roughly twice as large, 2.1 km, yielding mean size ratios (〈D_(LPC)〉/〈D_(JFC)〉) that differ by a factor of 1.6. Over the course of the 8 months of the survey, our results indicate that the number of LPCs passing within 1.5 au are a factor of several higher than previous estimates, while JFCs are within the previous range of estimates of a few thousand down to sizes near 1.3 km in diameter. Finally, we also observe evidence for structure in the orbital distribution of LPCs, with an overdensity of comets clustered near 110° inclination and perihelion near 2.9 au that is not attributable to observational bias. |
| Databáze: | OpenAIRE |
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