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Title: Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs)

Abstract

P/2011 S1 (Gibbs) is an outer solar system comet or active Centaur with a similar orbit to that of the famous 29P/Schwassmann-Wachmann 1. P/2011 S1 (Gibbs) has been observed by the Pan-STARRS 1 (PS1) sky survey from 2010 to 2012. The resulting data allow us to perform multi-color studies of the nucleus and coma of the comet. Analysis of PS1 images reveals that P/2011 S1 (Gibbs) has a small nucleus <4 km radius, with colors g {sub P1} – r {sub P1} = 0.5 ± 0.02, r {sub P1} – i {sub P1} = 0.12 ± 0.02, and i {sub P1} – z {sub P1} = 0.46 ± 0.03. The comet remained active from 2010 to 2012, with a model-dependent mass-loss rate of ∼100 kg s{sup –1}. The mass-loss rate per unit surface area of P/2011 S1 (Gibbs) is as high as that of 29P/Schwassmann-Wachmann 1, making it one of the most active Centaurs. The mass-loss rate also varies with time from ∼40 kg s{sup –1} to 150 kg s{sup –1}. Due to its rather circular orbit, we propose that P/2011 S1 (Gibbs) has 29P/Schwassmann-Wachmann 1-like outbursts that control the outgassing rate. The results indicate that it may have amore » similar surface composition to that of 29P/Schwassmann-Wachmann 1. Our numerical simulations show that the future orbital evolution of P/2011 S1 (Gibbs) is more similar to that of the main population of Centaurs than to that of 29P/Schwassmann-Wachmann 1. The results also demonstrate that P/2011 S1 (Gibbs) is dynamically unstable and can only remain near its current orbit for roughly a thousand years.« less

Authors:
; ;  [1];  [2];  [3]; ;  [4]; ; ; ; ; ; ; ;  [5];  [6]
  1. Institute of Astronomy, National Central University, Taoyuan 32001, Taiwan (China)
  2. Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan (China)
  3. Astrophysics Research Centre, School of Mathematics and Physics, Queens University Belfast, Belfast BT7 1NN (United Kingdom)
  4. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  5. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
  6. Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)
Publication Date:
OSTI Identifier:
22340263
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 147; Journal Issue: 5; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COLOR; COMETS; COMPUTERIZED SIMULATION; CONTROL; CURRENTS; DEGASSING; EVOLUTION; IMAGES; MASS TRANSFER; ORBITS; SKY; SOLAR SYSTEM; STELLAR WINDS; SURFACE AREA; SURFACES

Citation Formats

Lin, H. W., Ip, W. H., Chen, W. P., Chen, Y. T., Lacerda, P., Holman, M., Protopapas, P., Burgett, W. S., Chambers, K. C., Flewelling, H., Huber, M. E., Jedicke, R., Kaiser, N., Magnier, E. A., Metcalfe, N., and Price, P. A., E-mail: edlin@gm.astro.ncu.edu.tw. Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs). United States: N. p., 2014. Web. doi:10.1088/0004-6256/147/5/114.
Lin, H. W., Ip, W. H., Chen, W. P., Chen, Y. T., Lacerda, P., Holman, M., Protopapas, P., Burgett, W. S., Chambers, K. C., Flewelling, H., Huber, M. E., Jedicke, R., Kaiser, N., Magnier, E. A., Metcalfe, N., & Price, P. A., E-mail: edlin@gm.astro.ncu.edu.tw. Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs). United States. doi:10.1088/0004-6256/147/5/114.
Lin, H. W., Ip, W. H., Chen, W. P., Chen, Y. T., Lacerda, P., Holman, M., Protopapas, P., Burgett, W. S., Chambers, K. C., Flewelling, H., Huber, M. E., Jedicke, R., Kaiser, N., Magnier, E. A., Metcalfe, N., and Price, P. A., E-mail: edlin@gm.astro.ncu.edu.tw. Thu . "Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs)". United States. doi:10.1088/0004-6256/147/5/114.
@article{osti_22340263,
title = {Pan-STARRS 1 observations of the unusual active Centaur P/2011 S1(Gibbs)},
author = {Lin, H. W. and Ip, W. H. and Chen, W. P. and Chen, Y. T. and Lacerda, P. and Holman, M. and Protopapas, P. and Burgett, W. S. and Chambers, K. C. and Flewelling, H. and Huber, M. E. and Jedicke, R. and Kaiser, N. and Magnier, E. A. and Metcalfe, N. and Price, P. A., E-mail: edlin@gm.astro.ncu.edu.tw},
abstractNote = {P/2011 S1 (Gibbs) is an outer solar system comet or active Centaur with a similar orbit to that of the famous 29P/Schwassmann-Wachmann 1. P/2011 S1 (Gibbs) has been observed by the Pan-STARRS 1 (PS1) sky survey from 2010 to 2012. The resulting data allow us to perform multi-color studies of the nucleus and coma of the comet. Analysis of PS1 images reveals that P/2011 S1 (Gibbs) has a small nucleus <4 km radius, with colors g {sub P1} – r {sub P1} = 0.5 ± 0.02, r {sub P1} – i {sub P1} = 0.12 ± 0.02, and i {sub P1} – z {sub P1} = 0.46 ± 0.03. The comet remained active from 2010 to 2012, with a model-dependent mass-loss rate of ∼100 kg s{sup –1}. The mass-loss rate per unit surface area of P/2011 S1 (Gibbs) is as high as that of 29P/Schwassmann-Wachmann 1, making it one of the most active Centaurs. The mass-loss rate also varies with time from ∼40 kg s{sup –1} to 150 kg s{sup –1}. Due to its rather circular orbit, we propose that P/2011 S1 (Gibbs) has 29P/Schwassmann-Wachmann 1-like outbursts that control the outgassing rate. The results indicate that it may have a similar surface composition to that of 29P/Schwassmann-Wachmann 1. Our numerical simulations show that the future orbital evolution of P/2011 S1 (Gibbs) is more similar to that of the main population of Centaurs than to that of 29P/Schwassmann-Wachmann 1. The results also demonstrate that P/2011 S1 (Gibbs) is dynamically unstable and can only remain near its current orbit for roughly a thousand years.},
doi = {10.1088/0004-6256/147/5/114},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 5,
volume = 147,
place = {United States},
year = {Thu May 01 00:00:00 EDT 2014},
month = {Thu May 01 00:00:00 EDT 2014}
}
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