Evaluation of short-term temporal evolution of Pluto's surface composition from 2014-2017 with APO/TripleSpec

التفاصيل البيبلوغرافية
العنوان: Evaluation of short-term temporal evolution of Pluto's surface composition from 2014-2017 with APO/TripleSpec
المؤلفون: Holler, Bryan J., Yanez, Maya D., Protopapa, Silvia, Young, Leslie A., Verbiscer, Anne J., Chanover, Nancy J., Grundy, William M.
سنة النشر: 2021
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Earth and Planetary Astrophysics
الوصف: In this work we present the results of a spectral observing campaign of Pluto to search for temporal changes in surface composition on 1- to 3-year timescales. Near-infrared spectra of Pluto were obtained from June 2014 to August 2017 with the TripleSpec cross-dispersed spectrograph at the Apache Point Observatory's 3.5-meter Astrophysical Research Consortium (ARC) telescope. Observations were requested in order to obtain spectra of approximately the same sub-observer hemisphere $\sim$14 months apart, thus removing the effects of viewing geometry and rotation phase. Comparison of the CH$_4$ (methane) band areas and band center shifts between each component of these "matched pairs" revealed a surface in transition. Band areas for the 1.66 and 1.72 $\mu$m CH$_4$ absorption features exhibited a $>$5-$\sigma$ increase between 2014-06-17 and 2015-08-19, corresponding to a sub-observer hemisphere centered at $\sim$280$^{\circ}$E, with the latter date only 1 month after the New Horizons flyby of Pluto. The majority of matched pairs were obtained of the anti-Charon hemisphere, home to the bright, volatile-rich Sputnik Planitia, and did not present statistically significant changes in CH$_4$ band areas. CH$_4$ band center shifts, which provide information on the mixing state of CH$_4$ and N$_2$ in solid solution, were calculated between components of each matched pair, with no significant band shifts detected. The favored explanation for these combined results is the sublimation of more-volatile N$_2$ from the northern latitudes of Pluto in the lead-up to northern hemisphere summer solstice in 2029, leading to an increase in CH$_4$ concentration.
Comment: 28 pages, 8 figures, 5 tables
نوع الوثيقة: Working Paper
DOI: 10.1016/j.icarus.2021.114729
URL الوصول: http://arxiv.org/abs/2110.00662
رقم الأكسشن: edsarx.2110.00662
قاعدة البيانات: arXiv
الوصف
DOI:10.1016/j.icarus.2021.114729