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9. Pluto's haze as a surface material

Author

Grundy, W.M., Bertrand, T., Binzel, R.P., Buie, M.W., Buratti, B.J., Cheng, A.F., Cook, J.C., Cruikshank, D.P., Devins, S.L., Dalle Ore, C.M., Earle, A.M., Ennico, K., Forget, F., Gao, P., Gladstone, G.R., Howett, C.J.A., Jennings, D.E., Kammer, J.A., Lauer, T.R., Linscott, I.R., Lisse, C.M., Lunsford, A.W., McKinnon, W.B., Olkin, C.B., Parker, A.H., Protopapa, S., Quirico, E., Reuter, D.C., Schmitt, B., Singer, K.N., Spencer, J.A., Stern, S.A., Strobel, D.F., Summers, M.E., Weaver, H.A., Weigle, G.E., II, Wong, M.L., Young, E.F., Young, L.A., and Zhang, X.

Published
2018
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13. The 67P/Churyumov–Gerasimenko observation campaign in support of the Rosetta mission

Author

Snodgrass, C., A'Hearn, M. F., Aceituno, F., Afanasiev, V., Bagnulo, S., Bauer, J., Bergond, G., Besse, S., Biver, N., Bodewits, D., Boehnhardt, H., Bonev, B. P., Borisov, G., Carry, B., Casanova, V., Cochran, A., Conn, B. C., Davidsson, B., Davies, J. K., de León, J., de Mooij, E., de Val-Borro, M., Delacruz, M., DiSanti, M. A., Drew, J. E., Duffard, R., Edberg, N. J. T., Faggi, S., Feaga, L., Fitzsimmons, A., Fujiwara, H., Gibb, E. L., Gillon, M., Green, S. F., Guijarro, A., Guilbert-Lepoutre, A., Gutiérrez, P. J., Hadamcik, E., Hainaut, O., Haque, S., Hedrosa, R., Hines, D., Hopp, U., Hoyo, F., Hutsemékers, D., Hyland, M., Ivanova, O., Jehin, E., Jones, G. H., Keane, J. V., Kelley, M. S. P., Kiselev, N., Kleyna, J., Kluge, M., Knight, M. M., Kokotanekova, R., Koschny, D., Kramer, E. A., López-Moreno, J. J., Lacerda, P., Lara, L. M., Lasue, J., Lehto, H. J., Levasseur-Regourd, A. C., Licandro, J., Lin, Z. Y., Lister, T., Lowry, S. C., Mainzer, A., Manfroid, J., Marchant, J., McKay, A. J., McNeill, A., Meech, K. J., Micheli, M., Mohammed, I., Monguió, M., Moreno, F., Muñoz, O., Mumma, M. J., Nikolov, P., Opitom, C., Ortiz, J. L., Paganini, L., Pajuelo, M., Pozuelos, F. J., Protopapa, S., Pursimo, T., Rajkumar, B., Ramanjooloo, Y., Ramos, E., Ries, C., Riffeser, A., Rosenbush, V., Rousselot, P., Ryan, E. L., Santos-Sanz, P., Schleicher, D. G., Schmidt, M., Schulz, R., Sen, A. K., Somero, A., Sota, A., Stinson, A., Sunshine, J.M., Thompson, A., Tozzi, G. P., Tubiana, C., Villanueva, G. L., Wang, X., Wooden, D. H., Yagi, M., Yang, B., Zaprudin, B., and Zegmott, T. J.

Published
2017

14. Inflight radiometric calibration of New Horizons’ Multispectral Visible Imaging Camera (MVIC)

Author

Howett, C.J.A., Parker, A.H., Olkin, C.B., Reuter, D.C., Ennico, K., Grundy, W.M., Graps, A.L., Harrison, K.P., Throop, H.B., Buie, M.W., Lovering, J.R., Porter, S.B., Weaver, H.A., Young, L.A., Stern, S.A., Beyer, R.A., Binzel, R.P., Buratti, B.J., Cheng, A.F., Cook, J.C., Cruikshank, D.P., Dalle Ore, C.M., Earle, A.M., Jennings, D.E., Linscott, I.R., Lunsford, A.W., Parker, J.W.m., Phillippe, S., Protopapa, S., Quirico, E., Schenk, P.M., Schmitt, B., Singer, K.N., Spencer, J.R., Stansberry, J.A., Tsang, C.C.C., Weigle, G.E., II, and Verbiscer, A.J.

Published
2017
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15. Physical state and distribution of materials at the surface of Pluto from New Horizons LEISA imaging spectrometer

Author

Schmitt, B., Philippe, S., Grundy, W.M., Reuter, D.C., Côte, R., Quirico, E., Protopapa, S., Young, L.A., Binzel, R.P., Cook, J.C., Cruikshank, D.P., Dalle Ore, C.M., Earle, A.M., Ennico, K., Howett, C.J.A., Jennings, D.E., Linscott, I.R., Lunsford, A.W., Olkin, C.B., Parker, A.H., Parker, J.Wm., Singer, K.N., Spencer, J.R., Stansberry, J.A., Stern, S.A., Tsang, C.C.C., Verbiscer, A.J., and Weaver, H.A.

Published
2017
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17. Surface compositions across Pluto and Charon

Author

Grundy, W. M., Binzel, R. P., Buratti, B. J., Cook, J. C., Cruikshank, D. P., Ore, C. M. Dalle, Earle, A. M., Ennico, K., Howett, C. J. A., Lunsford, A. W., Olkin, C. B., Parker, A. H., Philippe, S., Protopapa, S., Quirico, E., Reuter, D. C., Schmitt, B., Singer, K. N., Verbiscer, A. J., Beyer, R. A., Buie, M. W., Cheng, A. F., Jennings, D. E., Linscott, I. R., Parker, J. Wm., Schenk, P. M., Spencer, J. R., Stansberry, J. A., Stern, S. A., Throop, H. B., Tsang, C. C. C., Weaver, H. A., Weigle, G. E., and Young, L. A.

Published
2016

18. The small satellites of Pluto as observed by New Horizons

Author

Weaver, H. A., Buie, M. W., Buratti, B. J., Grundy, W. M., Lauer, T. R., Olkin, C. B., Parker, A. H., Porter, S. B., Showalter, M. R., Spencer, J. R., Stern, S. A., Verbiscer, A. J., McKinnon, W. B., Moore, J. M., Robbins, S. J., Schenk, P., Singer, K. N., Barnouin, O. S., Cheng, A. F., Ernst, C. M., Lisse, C. M., Jennings, D. E., Lunsford, A. W., Reuter, D. C., Hamilton, D. P., Kaufmann, D. E., Ennico, K., Young, L. A., Beyer, R. A., Binzel, R. P., Bray, V. J., Chaikin, A. L., Cook, J. C., Cruikshank, D. P., Ore, C. M. Dalle, Earle, A. M., Gladstone, G. R., Howett, C. J. A., Linscott, I. R., Nimmo, F., Parker, J. Wm., Philippe, S., Protopapa, S., Reitsema, H. J., Schmitt, B., Stryk, T., Summers, M. E., Tsang, C. C. C., Throop, H. H. B., White, O. L., and Zangari, A. M.

Published
2016

20. The Pluto system: Initial results from its exploration by New Horizons

Author

Stern, S. A., Bagenal, F., Ennico, K., Gladstone, G. R., Grundy, W. M., McKinnon, W. B., Moore, J. M., Olkin, C. B., Spencer, J. R., Weaver, H. A., Young, L. A., Andert, T., Andrews, J., Banks, M., Bauer, B., Bauman, J., Barnouin, O. S., Bedini, P., Beisser, K., Beyer, R. A., Bhaskaran, S., Binzel, R. P., Birath, E., Bird, M., Bogan, D. J., Bowman, A., Bray, V. J., Brozovic, M., Bryan, C., Buckley, M. R., Buie, M. W., Buratti, B. J., Bushman, S. S., Calloway, A., Carcich, B., Cheng, A. F., Conard, S., Conrad, C. A., Cook, J. C., Cruikshank, D. P., Custodio, O. S., Ore, C. M. Dalle, Deboy, C., Dischner, Z. J. B., Dumont, P., Earle, A. M., Elliott, H. A., Ercol, J., Ernst, C. M., Finley, T., Flanigan, S. H., Fountain, G., Freeze, M. J., Greathouse, T., Green, J. L., Guo, Y., Hahn, M., Hamilton, D. P., Hamilton, S. A., Hanley, J., Harch, A., Hart, H. M., Hersman, C. B., Hill, A., Hill, M. E., Hinson, D. P., Holdridge, M. E., Horanyi, M., Howard, A. D., Howett, C. J. A., Jackman, C., Jacobson, R. A., Jennings, D. E., Kammer, J. A., Kang, H. K., Kaufmann, D. E., Kollmann, P., Krimigis, S. M., Kusnierkiewicz, D., Lauer, T. R., Lee, J. E., Lindstrom, K. L., Linscott, I. R., Lisse, C. M., Lunsford, A. W., Mallder, V. A., Martin, N., McComas, D. J., McNutt, R. L., Mehoke, D., Mehoke, T., Melin, E. D., Mutchler, M., Nelson, D., Nimmo, F., Nunez, J. I., Ocampo, A., Owen, W. M., Paetzold, M., Page, B., Parker, A. H., Parker, J. W., Pelletier, F., Peterson, J., Pinkine, N., Piquette, M., Porter, S. B., Protopapa, S., Redfern, J., Reitsema, H. J., Reuter, D. C., Roberts, J. H., Robbins, S. J., Rogers, G., Rose, D., Runyon, K., Retherford, K. D., Ryschkewitsch, M. G., Schenk, P., Schindhelm, E., Sepan, B., Showalter, M. R., Singer, K. N., Soluri, M., Stanbridge, D., Steffl, A. J., Strobel, D. F., Stryk, T., Summers, M. E., Szalay, J. R., Tapley, M., Taylor, A., Taylor, H., Throop, H. B., Tsang, C. C. C., Tyler, G. L., Umurhan, O. M., Verbiscer, A. J., Versteeg, M. H., Vincent, M., Webbert, R., Weidner, S., Weigle, G. E., White, O. L., Whittenburg, K., Williams, B. G., Williams, K., Williams, S., Woods, W. W., Zangari, A. M., and Zirnstein, E.

Published
2015

24. PLANETARY SCIENCE: The small satellites of Pluto as observed by New Horizons

Author

Weaver, H. A., Buie, M. W., Buratti, B. J., Grundy, W. M., Lauer, T. R., Olkin, C. B., Parker, A. H., Porter, S. B., Showalter, M. R., Spencer, J. R., Stern, S. A., Verbiscer, A. J., McKinnon, W. B., Moore, J. M., Robbins, S. J., Schenk, P., Singer, K. N., Barnouin, O. S., Cheng, A. F., Ernst, C. M., Lisse, C. M., Jennings, D. E., Lunsford, A. W., Reuter, D. C., Hamilton, D. P., Kaufmann, D. E., Ennico, K., Young, L. A., Beyer, R. A., Binzel, R. P., Bray, V. J., Chaikin, A. L., Cook, J. C., Cruikshank, D. P., Dalle Ore, C. M., Earle, A. M., Gladstone, G. R., Howett, C. J.A., Linscott, I. R., Nimmo, F., Parker, J. Wm., Philippe, S., Protopapa, S., Reitsema, H. J., Schmitt, B., Stryk, T., Summers, M. E., Tsang, C. C.C., Throop, H. H.B., White, O. L., and Zangari, A. M.

Published
2016
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25. PLANETARY SCIENCE: Surface compositions across Pluto and Charon

Author

Grundy, W. M., Binzel, R. P., Buratti, B. J., Cook, J. C., Cruikshank, D. P., Dalle Ore, C. M., Earle, A. M., Ennico, K., Howett, C. J.A., Lunsford, A. W., Olkin, C. B., Parker, A. H., Philippe, S., Protopapa, S., Quirico, E., Reuter, D. C., Schmitt, B., Singer, K. N., Verbiscer, A. J., Beyer, R. A., Buie, M. W., Cheng, A. F., Jennings, D. E., Linscott, I. R., Parker, J. Wm., Schenk, P. M., Spencer, J. R., Stansberry, J. A., Stern, S. A., Throop, H. B., Tsang, C. C.C., Weaver, H. A., Weigle, G. E., II, and Young, L. A.

Published
2016
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27. PLANETARY SCIENCE: The Pluto system: Initial results from its exploration by New Horizons

Author

Stern, S. A., Bagenal, F., Ennico, K., Gladstone, G. R., Grundy, W. M., McKinnon, W. B., Moore, J. M., Olkin, C. B., Spencer, J. R., Weaver, H. A., Young, L. A., Andert, T., Andrews, J., Banks, M., Bauer, B., Bauman, J., Barnouin, O. S., Bedini, P., Beisser, K., Beyer, R. A., Bhaskaran, S., Binzel, R. P., Birath, E., Bird, M., Bogan, D. J., Bowman, A., Bray, V. J., Brozovic, M., Bryan, C., Buckley, M. R., Buie, M. W., Buratti, B. J., Bushman, S. S., Calloway, A., Carcich, B., Cheng, A. F., Conard, S., Conrad, C. A., Cook, J. C., Cruikshank, D. P., Custodio, O. S., Ore, Dalle C. M., Deboy, C., Dischner, Z. J. B., Dumont, P., Earle, A M., Elliott, H. A, Ercol, J., Ernst, C. M., Finley, T., Flanigan, S. H., Fountain, G., Freeze, M. J., Greathouse, T., Green, J. L., Guo, Y., Hahn, M., Hamilton, D. P., Hamilton, S. A., Hanley, J., Harch, A., Hart, H. M., Hersman, C. B., Hill, A., Hill, M. E., Hinson, D. P., Holdridge, M. E., Horanyi, M., Howard, A. D., Howett, C. J. A., Jackman, C., Jacobson, R. A., Jennings, D. E., Kammer, J. A., Kang, H. K., Kaufmann, D. E., Kollmann, P., Krimigis, S. M., Kusnierkiewicz, D., Lauer, T. R., Lee, J. E., Lindstrom, K. L., Linscott, I. R., Lisse, C. M., Lunsford, A. W., Mallder, V. A., Martin, N., McComas, D. J., McNutt, R. L., Jr., Mehoke, D., Mehoke, T., Melin, E. D., Mutchler, M., Nelson, D., Nimmo, F., Nunez, J. I., Ocampo, A., Owen, W. M., Paetzold, M., Page, B., Parker, A. H., Parker, J. W., Pelletier, F., Peterson, J., Pinkine, N., Piquette, M., Porter, S. B., Protopapa, S., Redfern, J., Reitsema, H. J., Reuter, D. C., Roberts, J. H., Bobbins, S. J., Rogers, G., Rose, D., Runyon, K., Retherford, K. D., Ryschkewitsch, M. G., Schenk, P., Schindhelm, E., Sepan, B., Showalter, M. R., Singer, K. N., Soluri, M., Stanbridge, D., Steffl, A. J., Strobel, D. F., Stryk, T., Summers, M. E., Szalay, J. R., Tapley, M., Taylor, A., Taylor, H., Throop, H. B., Tsang, C. C. C., Tyler, G. L., Umurhan, O. M., Verbiscer, A. J., Versteeg, M. H., Vincent, M., Webbert, R., Weidner, S., Weigle, G. E., II, White, O. L., Whittenburg, K., Williams, B. G., Williams, K., Williams, S., Woods, W. W., Zangari, A. M., and Zirnstein, E.

Published
2015
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28. Far‐Ultraviolet Photometric Characteristics of JSC‐1A and LMS‐1 Lunar Regolith Simulants: Comparative Investigations With Apollo 10084.

Author

Gimar, C. J., Raut, U., Poston, M. J., Stevanovic, A., Protopapa, S., Greathouse, T. K., Retherford, K. D., Friday, J. M., and Grimes, J. T.

Subjects
LUNAR soil, LUNAR craters, SPACE environment, ENERGY dispersive X-ray spectroscopy, SOIL moisture, SPECTRAL reflectance, LIGHT scattering
Abstract

We have characterized the far‐ultraviolet (FUV) spectro‐photometric response of lunar soil simulants JSC‐1A and LMS‐1, reporting notable differences from our previous results for Apollo soil 10084 (Raut et al., 2018, https://doi.org/10.1029/2018JE005567). While JSC‐1A and LMS‐1 were designed to emulate the geotechnical and compositional properties of a low‐Ti and high‐Ti mare soil respectively, these terrestrial simulants lack "space weathering" attributes such as the nanophase iron present in the weathered rims of Apollo grains and glassy agglutinates. Photometric analyses of the JSC‐1A phase curves reveal a ∼3–4 fold increase in single scattering albedo (SSA) and a forward scattering behavior compared to 10084. LMS‐1 is shown to have SSA nearly twice that of 10084 and a near isotropic reflectance. Additionally, both JSC‐1A and LMS‐1 spectra present a blue slope in the FUV, with the JSC‐1A slope ∼10× larger than that reported for the 10084 soil. Our analyses imply that low‐Ti content corroborated using energy dispersive x‐ray spectroscopy, correlates to brighter FUV reflectance and a greater spectral blue slope for JSC‐1A, while space weathering components likely contribute to the backscattering of FUV light by the Apollo soil relative to both simulants. Further work with an extended set of Apollo soils is warranted to deconvolute the relative contributions of weathering and composition to their FUV spectro‐photometric response. Plain Language Summary: We compare the far‐ultraviolet (115–200 nm) reflectance properties of the lunar mare soil simulants JSC‐1A and LMS‐1 to that of Apollo soil 10084, a lunar mare soil collected by the Apollo 11 mission at Mare Tranquillitatis. The reflectance spectra of both simulants and the Apollo 10084 sample show a blue slope, meaning they reflect more light at shorter wavelengths. Previous studies have linked this blue slope in lunar soils to space weathering features, although our results point to other compositional differences such as titanium‐bearing mineral content influencing this phenomenon. JSC‐1A and LMS‐1 scatter far‐ultraviolet light either away from the direction of incidence (forward scattering) or in all directions (isotropic), while Apollo 10084 scatters light toward the direction of incidence (backscattering). The backscattering observed in Apollo 10084 may be a result of nanophase iron generated in the exterior rims of the soil grains through the reduction of native iron oxide by solar wind and micrometeorites, a space weathering feature not present in the terrestrial simulants. Key Points: We compare far‐UV bidirectional reflectance of JSC‐1A, LMS‐1, and Apollo 10084 soil to deconvolute space weathering and composition effectsJSC‐1A is brighter in the far‐UV and shows a steeper blue spectral slope than LMS‐1 and Apollo 10084, consistent with its low Ti contentJSC‐1A and LMS‐1 mostly forward scatter in the far‐UV, likely from the absence of space weathering features in backscattering 10084 grains [ABSTRACT FROM AUTHOR]

Published
2022
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30. The formation of Charons red poles from seasonally cold-trapped volatiles

Author

Grundy, W. M., Cruikshank, D. P., Gladstone, G. R., Howett, C. J. A., Lauer, T. R., Spencer, J. R., Summers, M. E., Buie, M. W., Earle, A. M., Ennico, K., Parker, J. Wm., Porter, S. B., Singer, K. N., Stern, S. A., Verbiscer, A. J., Beyer, R. A., Binzel, R. P., Buratti, B. J., Cook, J. C., Dalle Ore, C. M., Olkin, C. B., Parker, A. H., Protopapa, S., Quirico, E., Retherford, K. D., Robbins, S. J., Schmitt, B., Stansberry, J. A., Umurhan, O. M., Weaver, H. A., Young, L. A., Zangari, A. M., Bray, V. J., Cheng, A. F., McKinnon, W. B., McNutt, R. L., Moore, J. M., Nimmo, F., Reuter, D. C., Schenk, P. M., Bagenal, F., Andert, T., Barnouin, O., Bird, M., Brozovi, M., Elliott, H. A., Greathouse, T. K., Hahn, M., Hamilton, D. P., Hill, M. E., Hinson, D. P., Hofgartner, J., Hornyi, M., Howard, A. D., Jennings, D. E., Kammer, J. A., Kollmann, P., Lavvas, P., Linscott, I. R., Lisse, C. M., Lunsford, A. W., McComas, D. J., McNutt Jr., R. L., Mutchler, M., Nunez, J. I., Paetzold, M., Wm. Parker, J., Philippe, S., Piquette, M., Reitsema, H. J., Roberts, J. H., Runyon, K., Schindhelm, E., Showalter, M. R., Steffl, A. J., Strobel, D. F., Stryk, T., Szalay, J. R., Throop, H. B., Tsang, C. C. C., Tyler, G. L., Versteeg, M. H., Weigle II, G. E., White, O. L., Woods, W. W., and Young, E. F.

Subjects
Charon (Satellite) -- Natural history -- Observations, Pluto (Dwarf planet) -- Natural history -- Observations, Planetary atmospheres -- Natural history -- Observations, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Author(s): W. M. Grundy (corresponding author) [1]; D. P. Cruikshank [2]; G. R. Gladstone [3]; C. J. A. Howett [4]; T. R. Lauer [5]; J. R. Spencer [4]; M. E. [...]

Published
2016
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31. Kuiper Belt object 2014MU69, Pluto and Phoebe as windows on the composition of the early solar nebula.

Author

Pendleton, Y. J., Cruikshank, D. P., Stern, S. A., Dalle Ore, C. M., Grundy, W., Materese, C., Protopapa, S., Schmitt, B., Lisse, C., Salama, Farid, and Linnartz, Harold

Abstract

The initial chemical composition of a proto-planetary nebula depends upon the degree to which 1) organic and ice components form on dust grains, 2) organic and molecular species form in the gas phase, 3) organics and ices are exchanged between the gas and solid state, and 4) the precursor and newly formed (more complex) materials survive and are modified in the developing planetary system. Infrared and radio observations of star-forming regions reveal that complex chemistry occurs on icy grains, often before stars even form. Additional processing, through the proto-planetary disk (PPD) further modifies most, but not all, of the initial materials. In fact, the modern Solar System still carries a fraction of its interstellar inheritance (Alexander et al.2017). Here we focus on three examples of small bodies in our Solar System, each containing chemical and dynamical clues to its origin and evolution: the small-cold classical Kuiper Belt object (KBO) 2014 MU69, Pluto, and Saturn's moon, Phoebe. The New Horizons flyby of 2014 MU69 has given the first view of an unaltered body composed of material originally in the solar nebula at ~45 AU. The spectrum of MU69 reveals methanol ice (not commonly found), a possible detection of water ice, and the noteworthy absence of methane ice (Stern et al. 2019). Pluto's internal and surface inventory of volatiles and complex organics, together with active geological processes including cryo-volcanism, indicate a surprising level of activity on a body in the outermost region of the Solar System, and the fluid that emerges from subsurface reservoirs may contain material inherited from the solar nebula (Cruikshank et al.2019a,b). Meanwhile, Saturn's captured moon, Phoebe, carries high D/H in H2O (Clark et al. 2019) and complex organics (Cruikshank et al. 2008), both consistent with its formation in, and inheritance from, the outer region of the solar nebula. Together, these objects provide windows on the origin and evolution of our Solar System and constraints to be considered in future chemical and physical models of PPDs. [ABSTRACT FROM AUTHOR]

Published
2019
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32. Polarimetry of comets 67P/Churyumov–Gerasimenko, 74P/Smirnova–Chernykh, and 152P/Helin–Lawrence.

Author

Stinson, A., Bagnulo, S., Tozzi, G. P., Boehnhardt, H., Protopapa, S., Kolokolova, L., Muinonen, K., and Jones, G. H.

Abstract

Aims. Polarimetric characteristics of comets at large heliocentric distances is a relatively unexplored area; we extend the idea by adding and analysing the data for three Jupiter family comets (JFCs). Methods. With the FORS2 instrument of the ESO VLT, we performed quasi-simultaneous photometry and polarimetry of three active JFCs 67P/Churyumov-Gerasimenko, 74P/Smirnova-Chernykh, and 152P/Helin-Lawrence. Results. We obtained in total 23 polarimetric measurements at different epochs, covering a phase-angle range ∼1◦−16◦ and heliocentric distances from 3 to 4.6 au. From our observations we obtained both colour and polarimetric maps to look for structures in the comae and tails of the comets. Conclusions. 74P/Smirnova-Chernykh and 152P/Helin-Lawrence exhibit enough activity at large heliocentric distances to be detectable in polarimetric measurements. Polarimetric and colour maps indicate no evidence of dust particle evolution in the coma. From near-infrared spectra we find no evidence of water ice in the coma of comet 152P/Helin-Lawrence. [ABSTRACT FROM AUTHOR]

Published
2016
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33. The long-wavelength thermal emission of the Pluto-Charon system from Herschel observations. Evidence for emissivity effects.

Author

Lellouch, E., Santos-Sanz, P., Fornasier, S., Lim, T., Stansberry, J., Vilenius, E., Kiss, Cs., Müller, T., Protopapa, S., Panuzzo, P., and Moreno, R.

Subjects
WAVELENGTHS, PLUTO (Dwarf planet), CHARON (Satellite), EMISSIVITY
Abstract

Thermal observations of the Pluto-Charon system acquired by the Herschel Space Observatory in February 2012 are presented. They consist of photometric measurements with the PACS and SPIRE instruments (nine visits to the Pluto system each), covering six wavelengths from 70 to 500 µm altogether. The thermal light curve of Pluto-Charon is observed in all filters, albeit more marginally at 160 and especially 500 µm. Putting these data into the context of older ISO, Spitzer and ground-based observations indicates that the brightness temperature (TB) of the system (rescaled to a common heliocentric distance) drastically decreases with increasing wavelength, from ~53 K at 20 μm to ~35 K at 500 μm, and perhaps ever less at longer wavelengths. Considering a variety of diurnal and/or seasonal thermophysical models, we show that TB values of 35 K are lower than any expected temperature for the dayside surface or subsurface of Pluto and Charon, implying a low surface emissivity. Based on multiterrain modeling, we infer a spectral emissivity that decreases steadily from 1 at 20-25 μm to ~0.7 at 500 μm. This kind of behavior is usually not observed in asteroids (when proper allowance is made for subsurface sounding), but is found in several icy surfaces of the solar system. We tentatively identify that a combination of a strong dielectric constant and a considerable surface material transparency (typical penetration depth ~1 cm) is responsible for the effect. Our results have implications for the interpretation of the temperature measurements by REX/New Horizons at 4.2 cm wavelength. [ABSTRACT FROM AUTHOR]

Published
2016
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34. Colours of minor bodies in the outer solar system II. A statistical analysis revisited.

Author

Hainaut, O.R., Boehnhardt, H., and Protopapa, S.

Subjects
SOLAR system, ASTRONOMICAL photometry, KUIPER belt, SPECTRUM analysis, HISTOGRAMS
Abstract

We present an update of the visible and near-infrared colour database of Minor Bodies in the Outer Solar System (MBOSSes), which now includes over 2000 measurement epochs of 555 objects, extracted from over 100 articles. The list is fairly complete as of December 2011. The database is now large enough to enable any dataset with a large dispersion to be safely identified and rejected from the analysis. The selection method used is quite insensitive to individual outliers. Most of the rejected datasets were observed during the early days of MBOSS photometry. The individual measurements are combined in a way that avoids possible rotational artifacts. The spectral gradient over the visible range is derived from the colours, as well as the R absolute magnitude M(1, 1). The average colours, absolute magnitude, and spectral gradient are listed for each object, as well as the physico-dynamical classes using a classification adapted from Gladman and collaborators. Colour-colour diagrams, histograms, and various other plots are presented to illustrate and investigate class characteristics and trends with other parameters, whose significances are evaluated using standard statistical tests. Except for a small discrepancy for the J - H colour, the largest objects, with M(1, 1) < 5, are indistinguishable from the smaller ones. The larger ones are slightly bluer than the smaller ones in J - H. Short-period comets, Plutinos and other resonant objects, hot classical disk objects, scattered disk objects and detached disk objects have similar properties in the visible, while the cold classical disk objects and the Jupiter Trojans form two separate groups of their spectral properties in the visible wavelength range. The well-known colour bimodality of Centaurs is confirmed. The hot classical disk objects with large inclinations, or large orbital excitations are found to be bluer than the others, confirming a previously known result. Additionally, the hot classical disk objects with a smaller perihelion distance are bluer than those that do not come as close to the Sun. The bluer hot classical disk objects and resonant objects have fainter absolute magnitudes than the redder ones of the same class. Finally, we discuss possible scenarios for the origin of the colour diversity observed in MBOSSes, i.e. colouration caused by evolutionary or formation processes. The colour tables and all plots are also available on the MBOSS colour web page"", which will be updated when new measurements are published. [ABSTRACT FROM AUTHOR]

Published
2012
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35. "TNOs are Cool": A survey of the trans-Neptunian region VII. Size and surface characteristics of (90377) Sedna and 2010 EK139.

Author

Pál, A., Kiss, C., Müller, T. G., Santos-Sanz, P., Vilenius, E., Szalai, N., Mommert, M., Lellouch, E., Rengel, M., Hartogh, P., Protopapa, S., Stansberry, J., Ortiz, J.-L., Duffard, R., Thirouin, A., Henry, F., and Delsanti, A.

Subjects
ASTROPHYSICAL radiation, SOLAR radiation, ELECTROMAGNETIC waves, ASTRONOMY, SPECTRAL energy distribution, RADIATION
Abstract

We present estimates of the basic physical properties (size and albedo) of (90377) Sedna, a prominent member of the detached trans- Neptunian object population and the recently discovered scattered disk object 2010 EK139, based on the recent observations acquired with the Herschel Space Observatory, within the "TNOs are Cool!" key programme. Our modeling of the thermal measurements shows that both objects have larger albedos and smaller sizes than the previous expectations, thus their surfaces might be covered by ices in a significantly larger fraction. The derived diameter of Sedna and 2010 EK139 are 995 ± 80 km and 470+35-10 km, while the respective geometric albedos are pV =0.32 ± 0.06 and 0.25+0.02-0.05. These estimates are based on thermophysical model techniques. [ABSTRACT FROM AUTHOR]

Published
2012
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36. "TNOs are Cool": A survey of the trans-Neptunian region VI. Herschel*/PACS observations and thermal modeling of 19 classical Kuiper belt objects.

Author

Vilenius, E., Kiss, C., Mommert, M., Müller, T., Santos-Sanz, P., Pal, A., Stansberry, J., Mueller, M., Peixinho, N., Fornasier, S., Lellouch, E., Delsanti, A., Thirouin, A., Ortiz, J. L., Duffard, R., Perna, D., Szalai, N., Protopapa, S., Henry, F., and Hestroffer, D.

Subjects
TRANS-Neptunian objects, ASTEROIDS, KUIPER belt, SOLAR system, ASTRONOMY
Abstract

Context. Trans-Neptunian objects (TNO) represent the leftovers of the formation of the solar system. Their physical properties provide constraints to the models of formation and evolution of the various dynamical classes of objects in the outer solar system. Aims. Based on a sample of 19 classical TNOs we determine radiometric sizes, geometric albedos and beaming parameters. Our sample is composed of both dynamically hot and cold classicals. We study the correlations of diameter and albedo of these two subsamples with each other and with orbital parameters, spectral slopes and colors. Methods. We have done three-band photometric observations with Herschel/PACS and we use a consistent method for data reduction and aperture photometry of this sample to obtain monochromatic flux densities at 70.0, 100.0 and 160.0 μm. Additionally, we use Spitzer/MIPS flux densities at 23.68 and 71.42 μm when available, and we present new Spitzer flux densities of eight targets. We derive diameters and albedos with the near-Earth asteroid thermal model (NEATM). As auxiliary data we use reexamined absolute visual magnitudes from the literature and data bases, part of which have been obtained by ground based programs in support of our Herschel key program. Results. We have determined for the first time radiometric sizes and albedos of eight classical TNOs, and refined previous size and albedo estimates or limits of 11 other classicals. The new size estimates of 2002 MS4 and 120347 Salacia indicate that they are among the 10 largest TNOs known. Our new results confirm the recent findings that there are very diverse albedos among the classical TNOs and that cold classicals possess a high average albedo (0.17 ± 0.04). Diameters of classical TNOs strongly correlate with orbital inclination in our sample. We also determine the bulk densities of six binary TNOs. [ABSTRACT FROM AUTHOR]

Published
2012
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37. TNOs are cool: A survey of the trans-Neptunian region V. Physical characterization of 18 Plutinos using Herschel-PACS observations.

Author

Mommert, M., Harris, A. W., Kiss, C., Pál, A., Santos-Sanz, P., Stansberry, J., Delsanti, A., Vilenius, E., Müller, T. G., Peixinho, N., Lellouch, E., Szalai, N., Henry, F., Duffard, R., Fornasier, S., Hartogh, P., Mueller, M., Ortiz, J. L., Protopapa, S., and Rengel, M.

Subjects
PHOTOMETRY, TRANS-Neptunian objects, MONTE Carlo method, SOLAR system, ASTROPHYSICS
Abstract

Context. The Herschel open time key programme TNOs are Cool: A survey of the trans-Neptunian region aims to derive physical and thermal properties for a set of ∼140 Centaurs and trans-Neptunian objects (TNOs), including resonant, classical, detached and scattered disk objects. One goal of the project is to determine albedo and size distributions for specific classes and the overall population of TNOs. Aims. We present Herschel-PACS photometry of 18 Plutinos and determine sizes and albedos for these objects using thermal modeling. We analyze our results for correlations, draw conclusions on the Plutino size distribution, and compare to earlier results. Methods. Flux densities are derived from PACS mini scan-maps using specialized data reduction and photometry methods. In order to improve the quality of our results, we combine our PACS data with existing Spitzer MIPS data where possible, and refine existing absolute magnitudes for the targets. The physical characterization of our sample is done using a thermal model. Uncertainties of the physical parameters are derived using customized Monte Carlo methods. The correlation analysis is performed using a bootstrap Spearman rank analysis. Results. We find the sizes of our Plutinos to range from 150 to 730 km and geometric albedos to vary between 0.04 and 0.28. The average albedo of the sample is 0.08 ± 0.03, which is comparable to the mean albedo of Centaurs, Jupiter family comets and other TNOs. We were able to calibrate the Plutino size scale for the first time and find the cumulative Plutino size distribution to be best fit using a cumulative power law with q = 2 at sizes ranging from 120-400 km and q = 3 at larger sizes. We revise the bulk density of 1999 TC36 and find ϱ = 0.64+0.15 -0.11 g cm-3. On the basis of a modified Spearman rank analysis technique our Plutino sample appears to be biased with respect to object size but unbiased with respect to albedo. Furthermore, we find biases based on geometrical aspects and color in our sample. There is qualitative evidence that icy Plutinos have higher albedos than the average of the sample. [ABSTRACT FROM AUTHOR]

Published
2012
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38. "TNOs are Cool": A survey of the trans-Neptunian region IV. Size/albedo characterization of 15 scattered disk and detached objects observed with Herschel-PACS.

Author

Santos-Sanz, P., Lellouch, E., Fornasier, S., Kiss, C., Pal, A., Müller, T. G., Vilenius, E., Stansberry, J., Mommert, M., Delsanti, A., Mueller, M., Peixinho, N., Henry, F., Ortiz, J. L., Thirouin, A., Protopapa, S., Duffard, R., Szalai, N., Lim, T., and Ejeta, C.

Subjects
SCATTERED disk objects, MONTE Carlo method, STATISTICAL correlation, SOLAR system, ASTROPHYSICS
Abstract

Context. Physical characterization of trans-Neptunian objects, a primitive population of the outer solar system, may provide constraints on their formation and evolution. Aims. The goal of this work is to characterize a set of 15 scattered disk (SDOs) and detached objects, in terms of their size, albedo, and thermal properties. Methods. Thermal flux measurements obtained with the Herschel-PACS instrument at 70, 100 and 160 μm, and whenever applicable, with Spitzer-MIPS at 24 and 70 μm, are modeled with radiometric techniques, in order to derive the objects' individual size, albedo and when possible beaming factor. Error bars are obtained from a Monte-Carlo approach. We look for correlations between these and other physical and orbital parameters. Results. Diameters obtained for our sample range from 100 to 2400 km, and the geometric albedos (in V band) vary from 3.8% to 84.5%. The unweighted mean V geometric albedo for the whole sample is 11.2% (excluding Eris); 6.9% for the SDOs, and 17.0% for the detached objects (excluding Eris). We obtain new bulk densities for three binary systems: Ceto/Phorcys, Typhon/Echidna and Eris/Dysnomia. Apart from correlations clearly due to observational bias, we find significant correlations between albedo and diameter (more reflective objects being bigger), and between albedo, diameter and perihelion distance (brighter and bigger objects having larger perihelia). We discuss possible explanations for these correlations. [ABSTRACT FROM AUTHOR]

Published
2012
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40. ON THE DISEQUILIBRIUM OF PLUTO'S VOLATILES.

Author

Young, L. A., Tan, S. P., Trafton, L. M., Stansberry, Grundy, W. B., Protopapa, S., Schmitt, B., Umurhan, O. M., and Bertrand, T.

Subjects
THERMODYNAMIC equilibrium, PLANETARY science, SURFACE pressure, KIRKENDALL effect, PARTIAL pressure
Published
2019

41. PHOTOMETRIC PROPERTIES OF PLUTO'S MAIN SURFACE UNITS.

Author

Protopapa, S., Olkin, C., Grundy, W., Li, J. Y., Verbiscer, A., Cruikshank, D. P., Howett, C. J. A., Stem, A., Weaver, H. A., and Young, L. A.

Subjects
PLUTO (Dwarf planet), PROPERTY, HORIZON
Published
2019

42. THE COLORS AND PHOTOMETRIC PROPERTIES OF PLUTO.

Author

Olkin, C. B., Howett, C. J. A., Protopapa, S., Grundy, W. M., Buie, M. W., Verbiscer, A., Stern, S. A., Weaver, H. A., Young, L. A., and Ennico, K.

Subjects
PLUTO (Dwarf planet), COLORS, LIGHT filters
Published
2019

44. CHARON'S COLORS AND PHOTOMETRIC PROPERTIES.

Author

Howett, C. J. A., Olkin, C. B., Protopapa, S., Grundy, W. M., Verbiscer, A., and Buratti, B. J.

Subjects
PLUTO (Dwarf planet), COLORS, LIGHT filters
Published
2019

45. PLUTO'S SURFACE COMPOSITION.

Author

Grundy, W. M., Cruikshank, D. P., Protopapa, S., and Schmitt, B.

Subjects
PLUTO (Dwarf planet), HORIZON
Published
2019

48. CHARON'S SURFACE COMPOSITION.

Author

Cook, J. C., Protopapa, S., Cruikshank, D. P., Dalle Ore, C. M., and Grundy, W. M.

Subjects
PLUTO (Dwarf planet), VERY large telescopes
Published
2019

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