45 results on '"Pinilla-Alonso, N."'
Search Results
2. Measurement of D/H and 13C/12C ratios in methane ice on Eris and Makemake: Evidence for internal activity
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Grundy, W.M., Wong, I., Glein, C.R., Protopapa, S., Holler, B.J., Cook, J.C., Stansberry, J.A., Lunine, J.I., Parker, A.H., Hammel, H.B., Milam, S.N., Brunetto, R., Pinilla-Alonso, N., de Souza Feliciano, A.C., Emery, J.P., and Licandro, J.
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- 2024
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3. Physical and dynamical characterization of hyperbolic comet C/2017 U7 (PANSTARRS)
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Evangelista-Santana, M., Carvano, J.M., De Prá, M., de la Fuente Marcos, R., Schambeau, C., Licandro, J., de la Fuente Marcos, C., Souza-Feliciano, A.C., and Pinilla-Alonso, N.
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- 2022
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4. Analysis in the visible range of NASA Lucy mission targets: Eurybates, Polymele, Orus and Donaldjohanson.
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Souza-Feliciano, A.C., De Prá, M., Pinilla-Alonso, N., Alvarez-Candal, A., Fernández-Valenzuela, E., De León, J., Binzel, R., Arcoverde, P., Rondón, E., and Evangelista, M.S
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- 2020
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5. The spectroscopic properties of the Lixiaohua family, cradle of Main Belt Comets
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De Prá, M.N., Licandro, J., Pinilla-Alonso, N., Lorenzi, V., Rondón, E., Carvano, J., Morate, D., and De León, J.
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- 2020
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6. Expected spectral characteristics of (101955) Bennu and (162173) Ryugu, targets of the OSIRIS-REx and Hayabusa2 missions
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de León, J., Campins, H., Morate, D., De Prá, M., Alí-Lagoa, V., Licandro, J., Rizos, J.L., Pinilla-Alonso, N., DellaGiustina, D.N., Lauretta, D.S., Popescu, M., and Lorenzi, V.
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- 2018
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7. PRIMASS visits Hilda and Cybele groups
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De Prá, M.N., Pinilla-Alonso, N., Carvano, J.M., Licandro, J., Campins, H., Mothé-Diniz, T., De León, J., and Alí-Lagoa, V.
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- 2018
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8. New polarimetric and spectroscopic evidence of anomalous enrichment in spinel-bearing calcium-aluminium-rich inclusions among L-type asteroids
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Devogèle, M., Tanga, P., Cellino, A., Bendjoya, Ph., Rivet, J.-P., Surdej, J., Vernet, D., Sunshine, J.M., Bus, S.J., Abe, L., Bagnulo, S., Borisov, G., Campins, H., Carry, B., Licandro, J., McLean, W., and Pinilla-Alonso, N.
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- 2018
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9. Visible spectroscopy of the Polana–Eulalia family complex: Spectral homogeneity
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de León, J., Pinilla-Alonso, N., Delbo, M., Campins, H., Cabrera-Lavers, A., Tanga, P., Cellino, A., Bendjoya, P., Gayon-Markt, J., Licandro, J., Lorenzi, V., Morate, D., Walsh, K.J., DeMeo, F., Landsman, Z., and Alí-Lagoa, V.
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- 2016
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10. James Webb Space Telescope Observations of Stellar Occultations by Solar System Bodies and Rings
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JWST “Occultations” Focus Group, Santos-Sanz, P., French, R. G., Pinilla-Alonso, N., Stansberry, J., Lin, Z-Y., Zhang, Z-W., Vilenius, E., Müller, Th., Ortiz, J. L., Braga-Ribas, F., Bosh, A., Duffard, R., Lellouch, E., Tancredi, G., Young, L., and Milam, Stefanie N.
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- 2016
11. Distribution of CO2 ice on the large moons of Uranus and evidence for compositional stratification of their near-surfaces
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Cartwright, R.J., Emery, J.P., Rivkin, A.S., Trilling, D.E., and Pinilla-Alonso, N.
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- 2015
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12. NEOROCKS Characterization Program of Near-Earth Asteroids Previously Observed with Radar
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de León, Julia, Licandro, Javier, Popescu, Marcel, Medeiros, Hissa, Morate, David, Pinilla-Alonso, N., and Pérez-Toledo, Fabricio
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Solar System ,NEOROCKS ,Asteroids ,Observations - Abstract
The NEO Rapid Observation, Characterization and Key Simulations (NEOROCKS) project is funded (2020-2023) through the H2020 European Commission program to improve our knowledge on near-Earth objects by connecting expertise in performing small body astronomical observations and the related modeling needed to derive their dynamical and physical properties. The Instituto de Astrofísica de Canarias (IAC), and in particular members of the Solar System Group, participate in the NEOROCKS project and currently lead one specific task: to collect observational data, mainly in the visible wavelengths, of NEAs that have been observed in the past using the Arecibo Planetary Radar. In this work we present preliminary results, focusing on those targets having high signal-to-noise ration radar data. 
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- 2022
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13. Near-infrared spectroscopic survey of B-type asteroids: Compositional analysis
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de León, J., Pinilla-Alonso, N., Campins, H., Licandro, J., and Marzo, G.A.
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- 2012
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14. James Webb Space Telescope Observations of Stellar Occultations by Solar System Bodies and Rings
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Santos-Sanz, P, French, R. G, Pinilla-Alonso, N, Stansberry, J, Lin, Z-Y, Zhang, Z-W, Vilenius, E, Mueller, Th, Ortiz, J. L, Braga-Ribas, F, Bosh, A, Duffard, R, Lellouch, E, Tancredi, G, Young, Leslie, and Milam, Stefanie N
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Astronomy - Abstract
In this paper, we investigate the opportunities provided by the James Webb Space Telescope (JWST) for significant scientific advances in the study of Solar System bodies and rings using stellar occultations. The strengths and weaknesses of the stellar occultation technique are evaluated in light of JWST's unique capabilities. We identify several possible JWST occultation events by minor bodies and rings and evaluate their potential scientific value. These predictions depend critically on accurate a priori knowledge of the orbit of JWST near the Sun–Earth Lagrange point 2 (L2). We also explore the possibility of serendipitous stellar occultations by very small minor bodies as a byproduct of other JWST observing programs. Finally, to optimize the potential scientific return of stellar occultation observations, we identify several characteristics of JWST's orbit and instrumentation that should be taken into account during JWST's development.
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- 2016
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15. The Future Of The Arecibo Observatory: The Next Generation Arecibo Telescope
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Roshi, D. Anish, Aponte, N., Araya, E., Arce, H., Baker, L. A., Baan, W., Becker, T. M., Breakall, J. K., Brown, R. G., Brum, C. G. M., Busch, M., Campbell, D. B., Cohen, T., Cordova, F., Deneva, J. S., Devogele, M., Dolch, T., Fernandez-Rodriguez, F. O., Ghosh, T., Goldsmith, P. F., Gurvits, L. I., Haynes, M., Heiles, C., Hessel, J. W. T., Hickson, D., Isham, B., Kerr, R. B., Kelly, J., Kiriazes, J. J., Lautenbach, J., Lebron, M., Lewandowska, N., Magnani, L., Manoharan, P. K., Margot, J. L., Marshall, S. E., McGilvray, A. K., Mendez, A., Minchin, R., Negron, V., Nolan, M. C., Olmi, L., Paganelli, F., Palliyaguru, N. T., Pantoja, C. A., Paragi, Z., Parshley, S. C., Peek, J. E. G., Perera, B. B. P., Perillat, P., Pinilla-Alonso, N., Quintero, L., Radovan, H., Raizada, S., Robishaw, T., Route, M., Salter, C. J., Santoni, A., Santos, P., Sau, S., Selvaraj, D., Smith, A. J., Sulzer, M., Vaddi, S., Vargas, F., Venditti, F. C. F., Venkataraman, A., Verkouter, H., Virkki, A. K., Vishwas, A., Weinreb, S., Werthimer, D., Wolszczan, A., and Zambrano-Marin, L. F.
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Physics - Atmospheric and Oceanic Physics ,Physics - Instrumentation and Detectors ,Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The Arecibo Observatory (AO) is a multidisciplinary research and education facility that is recognized worldwide as a leading facility in astronomy, planetary, and atmospheric and space sciences. AO's cornerstone research instrument was the 305-m William E. Gordon telescope. On December 1, 2020, the 305-m telescope collapsed and was irreparably damaged. In the three weeks following the collapse, AO's scientific and engineering staff and the AO users community initiated extensive discussions on the future of the observatory. The community is in overwhelming agreement that there is a need to build an enhanced, next-generation radar-radio telescope at the AO site. From these discussions, we established the set of science requirements the new facility should enable. These requirements can be summarized briefly as: 5 MW of continuous wave transmitter power at 2 - 6 GHz, 10 MW of peak transmitter power at 430 MHz (also at 220MHz under consideration), zenith angle coverage 0 to 48 deg, frequency coverage 0.2 to 30 GHz and increased Field-of-View. These requirements determine the unique specifications of the proposed new instrument. The telescope design concept we suggest consists of a compact array of fixed dishes on a tiltable, plate-like structure with a collecting area equivalent to a 300m dish. This concept, referred to as the Next Generation Arecibo Telescope (NGAT), meets all of the desired specifications and provides significant new science capabilities to all three research groups at AO. This whitepaper presents a sample of the wide variety of the science that can be achieved with the NGAT, the details of the telescope design concept and the need for the new telescope to be located at the AO site. We also discuss other AO science activities that interlock with the NGAT in the white paper., Comment: 82 pages (executive summary 10 pages), 21 figures, Arecibo observatory white paper (Updated with the complete author list and minor edits)
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- 2021
16. Compositional study of trans-Neptunian objects at {\lambda} > 2.2 {\mu}m
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Fernández-Valenzuela, E., Pinilla-Alonso, N., Stansberry, J., Emery, J. P., Perkins, W., Van Laerhoven, C., Gladman, B. J., Fraser, W., Cruikshank, D., Lellouch, E., Müller, T. G., Grundy, W. M., Trilling, D., Fernandez, Y., and Dalle-Ore, C.
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Astrophysics - Earth and Planetary Astrophysics - Abstract
Using data from the Infrared Array Camera on the Spitzer Space Telescope, we present photometric observations of a sample of 100 trans-Neptunian objects (TNOs) beyond 2.2 {\mu}m. These observations, collected with two broad-band filters centered at 3.6 and 4.5 {\mu}m, were done in order to study the surface composition of TNOs, which are too faint to obtain spectroscopic measurements. With this aim, we have developed a method for the identification of different materials that are found on the surfaces of TNOs. In our sample, we detected objects with colors that are consistent with the presence of small amounts of water and were able to distinguish between surfaces that are predominately composed of complex organics and amorphous silicates. We found that 86% of our sample have characteristics that are consistent with a certain amount of water ice, and the most common composition (73% of the objects) is a mixture of water ice, amorphous silicates, and complex organics. 23% of our sample may include other ices such as carbon monoxide, carbon dioxide, methane or methanol. Additionally, only small objects seem to have surfaces dominated by silicates. This method is a unique tool for the identification of complex organics and to obtain the surface composition of extremely faint objects. Also, this method will be beneficial when using the James Webb Space Telescope for differentiating groups within the trans-Neptunian population., Comment: Accepted for publication in PSJ on October 13, 2020
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- 2020
17. A peculiar family of Jupiter Trojans: The Eurybates
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De Luise, F., Dotto, E., Fornasier, S., Barucci, M.A., Pinilla-Alonso, N., Perna, D., and Marzari, F.
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Silicates ,Astronomy ,Water ,Universities and colleges ,Astronomy ,Earth sciences - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2010.04.024 Byline: F. De Luise (a)(b), E. Dotto (a), S. Fornasier (c)(d), M.A. Barucci (c), N. Pinilla-Alonso (e)(f), D. Perna (a)(c)(g), F. Marzari (h) Keywords: Trojan asteroids; Asteroids; surface; Asteroids; composition; Spectroscopy Abstract: The Eurybates family is a compact core inside the Menelaus clan, located in the L.sub.4 swarm of Jupiter Trojans. Fornasier et al. (Fornasier, S., Dotto, E., Hainaut, O., Marzari, F., Boehnhardt, H., De Luise, F., Barucci, M.A. [2007]. Icarus 190, 622-642) found that this family exhibits a peculiar abundance of spectrally flat objects, similar to Chiron-like Centaurs and C-type main belt asteroids. On the basis of the visible spectra available in literature, Eurybates family's members seemed to be good candidates for having on their surfaces water/water ice or aqueous altered materials. To improve our knowledge of the surface composition of this peculiar family, we carried out an observational campaign at the Telescopio Nazionale Galileo (TNG), obtaining near-infrared spectra of 7 members. Our data show a surprisingly absence of any spectral feature referable to the presence of water, ices or aqueous altered materials on the surface of the observed objects. Models of the surface composition are attempted, evidencing that amorphous carbon seems to dominate the surface composition of the observed bodies and some amount of silicates (olivine) could be present. Author Affiliation: (a) INAF - Osservatorio Astronomico di Roma, Via Frascati 33, 00040 Monteporzio Catone (Roma), Italy (b) INAF - Osservatorio Astronomico di Collurania-Teramo, Via Mentore Maggini, s.n.c., 64100 Teramo (TE), Italy (c) LESIA, Paris Observatory, 5 Place Jules Janssen, 92195 Meudon Cedex, France (d) University of Paris VII 'Denis Diderot', 4 rue Elsa Morante, 75013 Paris, France (e) Fundacion Galileo Galilei & Telescopio Nazionale Galileo, PO Box 565, 38700 S/C de La Palma, Tenerife, Spain (f) Oak Ridge Associated Universities (ORAU) - NASA Ames Research Center, MS 245-3, Moffett Field, CA 94035-1000, USA (g) University of Rome 'Tor Vergata', Via della Ricerca Scientifica 1, 00133 Roma, Italy (h) Dipartimento di Fisica - University of Padova, Via Marzolo 8, 35131 Padova, Italy Article History: Received 30 January 2009; Revised 23 April 2010; Accepted 28 April 2010 Article Note: (footnote) [star] Based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by the Fundacion Galileo Galilei of the INAF (Istituto Nazionale di Astrofisica) at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, programmes: TAC41(AOT14) and TAC69(AOT15).
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- 2010
18. Depth of a strong jovian jet from a planetary-scale disturbance driven by storms
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Sanchez-Lavega, A., Orton, G. S., Hueso, R., Garcia-Melendo, E., Perez-Hoyos, S., Simon-Miller, A., Rojas, J. F., Gomez, J. M., Yanamandra-Fisher, P., Fletcher, L., Joels, J., Kemerer, J., Hora, J., Karkoschka, E., de Pater, I., Wong, M. H., Marcus, P. S., Pinilla-Alonso, N., Carvalho, F., Go, C., Parker, D., Salway, M., Valimberti, M., Wesley, A., and Pujic, Z.
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Jupiter (Planet) -- Atmosphere -- Discovery and exploration -- Thermal properties ,Jets -- Thermal properties -- Discovery and exploration ,Environmental issues ,Science and technology ,Zoology and wildlife conservation ,Thermal properties ,Discovery and exploration ,Observations ,Composition ,Properties - Abstract
Author(s): A. Sánchez-Lavega (corresponding author) [1]; G. S. Orton [2]; R. Hueso [1]; E. GarcÃa-Melendo [3]; S. Pérez-Hoyos [1]; A. Simon-Miller [4]; J. F. Rojas [5]; J. M. Gómez [3]; [...]
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- 2008
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19. The Science Case for Spacecraft Exploration of the Uranian SatellitesA Science White Paper for the Planetary Science and Astrobiology Decadal Survey 2023-2032
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Cartwright, Richard, Beddingfield, Chloe, Nordheim, T, Elder, C., Grundy, W., Buratti, B., Bramson, A., Sori, M., Pappalardo, R., Neveu, M., Burr, D., Ermakov, A., Roser, J., Castillo-Rogez, J., Showalter, M., Cohen, I., Turtle, E., Hofstadter, M., Leonard, E., Pater, I. de, Patthoff, D.A., Masters, A., Fletcher, L., Ahrens, C., Andres, C., Aplin, K., Arney, G., Baillie, Kevin, Barth, E., Bennett, C., Beyer, R., Bierson, C., Bland, M., Bray, V., Byrne, P., Cabrol, N., Cameron, M., Chanover, N., Cochrane, C., Collins, G., Cook, J., Coustenis, A., Cruikshank, D., Ćuk, M., Daubar, I., Denton, A., DeColibus, D., Dhingra, R., Dong, C., Ferguson, S., Filacchione, G., French, R., Golder, K., Grava, C., Griton, L., Hammond, N., Hayes, A., Hawkins, E., Helfenstein, P., Hendrix, A., Hofmann, A., Holler, B., Holt, T., Howell, S., Howett, C., Hussmann, H., Hsu, H., Izenberg, N., Jacobsen, R., Jha, D., Juanola-Parramon, R., Jun, I., Keane, J., Karkoschka, E., Kattenhorn, S., Kinczyk, M., Kirchoff, M., Klimczak, C., Kollmann, P., Lopes, R., Lucas, M., Lucchetti, A., Martin, E., MacKenzie, S., Moses, J., Mlinar, A. Barr, Moore, J., Nimmo, F., O’Hara, S., Pajola, M., Peel, S., Peterson, G., Pinilla-Alonso, N., Porter, S., Postberg, F., Poston, M., Probst, A., Protopapa, S., Quick, L., Ricca, A., Roberge, A., Roberts, J., Robbins, S., Rodriguez, S., Runyon, K., Schenk, P., Schneegurt, M., Scipioni, F., Shusterman, M., Singer, K., Soderlund, K., Spencer, J., Spilker, L., Stephan, K., Stryk, T., Tiscareno, M., Tomlinson, T., Tosi, F., Tortora, P., Umurhan, O., Vance, S., Verbiscer, A., Walker, C., Weiss, B., White, O., Search for Extraterrestrial Intelligence Institute (SETI), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
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[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] - Abstract
A Science White Paper for the Planetary Science and Astrobiology Decadal Survey 2023-2032; Uranian satellites imaged by Voyager 2, not shown to scale (NASA/JPL-Caltech/USGS, [55]). Puck (top left), Miranda (top middle), Ariel (top right), Umbriel (bottom left), Titania (bottom middle), and Oberon (bottom right).
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- 2020
20. Spectroscopy of Pluto, 380-930 Nm at Six Longitudes
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Cruikshank, D. P, Pinilla-Alonso, N, Lorenzi, V, Grundy, William, Licandro, J, and Binzel, R. P
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Astrophysics - Abstract
We have obtained spectra of the Pluto-Charon pair (unresolved) in the wavelength range 380-930 nm with resolution approx..450 at six roughly equally spaced longitudes. The data were taken in May and June, 2014, with the 4.2-m Isaac Newton Telescope at Roque de Los Muchachos Observatory in the Canary Islands, using the ACAM (auxiliary-port camera) in spectrometer mode, and using two solar analog stars. The new spectra clearly show absorption bands of solid CH4 at 620, 728, and 850-910 nm, which were known from earlier work. The 620-nm CH4 band is intrinsically very weak, and its appearance indicates a long optical path-length through the ice. This is especially true if it arises from CH4 dissolved in N2 ice. Earlier work (Owen et al. Science 261, 745, 1993) on the near-infrared spectrum of Pluto (1-2.5 microns) has shown that the CH4 bands are shifted to shorter wavelengths because the CH4 occurs as a solute in beta-phase crystalline N2. The optical path-length through the N2 crystals must be on the order of several cm to produce the N2 band observed at 2.15 microns. The new spectra exhibit a pronounced red slope across the entire wavelength range; the slope is variable with longitude, and differs in a small but significant way from that measured at comparable longitudes by Grundy & Fink (Icarus 124, 329, 1996) in their 15-year study of Pluto's spectrum (500-1000 nm). The new spectra will provide an independent means for calibrating the color filter bands on the Multispectral Visible Imaging Camera (MVIC) (Reuter et al. Space Sci. Rev. 140, 129, 2008) on the New Horizons spacecraft, which will encounter the Pluto-Charon system in mid-2015. They will also form the basis of modeling the spectrum of Pluto at different longitudes to help establish the nature of the non-ice component(s) of Pluto's surface. It is presumed that the non-ice component is the source of the yellow-red coloration of Pluto, which is known to be variable across the surface.
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- 2014
21. Deep Impact: observations from a worldwide earth-based campaign
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Meech, K.J., Ageorges, N., A'Hearn, M.F., Arpigny, C., Ates, A., Aycock, J., Bagnulo, S., Bailey, J., Barber, R., Barrera, L., Barrena, R., Bauer, J.M., Belton, M.J.S., Bensch, F., Bhattacharya, B., Biver, N., Blake, G., Bockelee-Morvan, D., Boehnhardt, H., Bonev, B.P., Bonev, T., Buie, M.W., Burton, M.G., Butner, H.M., Cabanac, R., Campbell, R., Campins, H., Capria, M.T., Carroll, T., Chaffee, F., Charnley, S.B., Cleis, R., Coates, A., Cochran, A., Colom, P., Conrad, A., Coulson, I.M., Crovisier, J., deBuizer, J., Dekany, R., de Leon, J., Russo, N. Dello, Delsanti, A., DiSanti, M., Drummond, J., Dundon, L., Etzel, P.B., Farnham, T.L., Feldman, P., Fernandez, Y.R., Filipovic, M.D., Fisher, S., Fitzsimmons, A., Fong, D., Fugate, R., Fujiwara, H., Fujiyoshi, T., Furusho, R., Fuse, T., Gibb, E., Groussin, O., Gulkis, S., Gurwell, M., Hadamcik, E., Hainaut, O., Harker, D., Harrington, D., Harwit, M., Hasegawa, S., Hergenrother, C.W., Hirst, P., Hodapp, K., Honda, M., Howell, E.S., Hutsemekers, D., Iono, D., Ip, W.-H., Jackson, W., Jehin, E., Jiang, Z.J., Jones, G.H., Jones, P.A., Kadono, T., Kamath, U.W., Kaufl, H.U., Kasuga, T., Kawakita, H., Kelley, M.S., Kerber, F., Kidger, M., Kinoshita, D., Knight, M., Lara, L., Larson, S.M., Lederer, S., Lee, C.-F., Levasseur-Regourd, A.C., Li, J.Y., Li, Q.-S., Licandro, J., Lin, Z.-Y., Lisse, C.M., LoCurto, G., Lovell, A.J., Lowry, S.C., Lyke, J., Lynch, D., Ma, J., Magee-Sauer, K., Maheswar, G., Manfroid, J., Marco, O., Martin, P., Melnick, G., Miller, S., Miyata, T., Moriarty-Schieven, G.H., Moskovitz, N., Mueller, B.E.A., Mumma, M.J., Muneer, S., Neufeld, D.A., Ootsubo, T., Osip, D., Pandea, S.K., Pantin, E., Paterno-Mahler, R., Patten, B., Penprase, B.E., Peck, A., Petitas, G., Pinilla-Alonso, N., Pittichova, J., Pompei, E., Prabhu, T.P., Qi, C., Rao, R., Rauer, H., Reitsema, H., Rodgers, S.D., Rodriguez, P., Ruane, R., Ruch, G., Rujopakarn, W., Sahu, D.K., Sako, S., Sakon, I., Samarasinha, N., Sarkissian, J.M., Saviane, I., Schirmer, M., Schultz, P., Schulz, R., Seitzer, P., Sekiguchi, T., Selman, F., Serra-Ricart, H., Sharp, R., Snell, R.L., Snodgrass, C., Stallard, T., Stecklein, G., Sterken, C., Stuwe, J.A., Sugita, S., Sumner, M., Suntzeff, N., Swaters, R., Takakuwa, S., Takato, N., Thomas-Osip, J., Thompson, E., Tokunaga, A.T., Tozzi, G.P., Tran, H., Troy, M., Trujillo, C., Van Cleve, J., Vasundhara, R., Vazquez, R., Vilas, F., Villanueva, G., von Braun, K., Vora, P., Wainscoat, R.J., Walsh, K., Watanabe, J., Weaver, H.A., Weaver, W., Weiler, M., Weissman, P.R., Welsh, W.F., Wilner, D., Wolk, S., Womack, M., Wooden, D., Woodney, L.H., Woodward, C., Wu, Z.-Y., Wu, J.-H., Yamashita, T., Yang, B., Yang, Y.-B., Yokogawa, S., Zook, A.C., Zauderer, A., Zhao, X., Zhou, X., and Zucconi, J.-M.
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Tempel 1 comet -- Observations -- Research ,Earth -- Research ,Science and technology - Abstract
On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics., The Deep Impact mission was designed so that much of the mission-critical science would be done from Earth-based telescopes. These facilities would observe the comet before, during, and after impact [...]
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- 2005
22. Albedo and atmospheric constraints of dwarf planet Makemake from a stellar occultation
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Ortiz, J. L., Sicardy, B., Braga-Ribas, F., Alvarez-Candal, A., Lellouch, E., Duffard, R., Pinilla-Alonso, N., Ivanov, V. D., Littlefair, S. P., Camargo, J. I. B., Assafin, M., Unda-Sanzana, E., Jehin, E., Morales, N., Tancredi, G., Gil-Hutton, R., de la Cueva, I., Colque, J. P., Da Silva Neto, D. N., Manfroid, J., Thirouin, A., Gutiérrez, P. J., Lecacheux, J., Gillon, M., Maury, A., Colas, F., Licandro, J., Mueller, T., Jacques, C., Weaver, D., Milone, A., Salvo, R., Bruzzone, S., Organero, F., Behrend, R., Roland, S., Vieira-Martins, R., Widemann, T., Roques, F., Santos-Sanz, P., Hestroffer, D., Dhillon, V. S., Marsh, T. R., Harlingten, C., Bagatin, Campo A., Alonso, M. L., Ortiz, M., Colazo, C., Lima, H. J. F., Oliveira, A. S., Kerber, L. O., Smiljanic, R., Pimentel, E., Giacchini, B., Cacella, P., and Emilio, M.
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- 2012
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23. Mimas: Preliminary Evidence For Amorphous Water Ice from VIMS
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Cruikshank, Dale P, Marzo, G. A, Pinilla-Alonso, N, Roush, T. L, Mastrapa, R. M, DalleOre, C. M, Buratti, B. J, and Stephan, K
- Subjects
Geophysics - Abstract
We have conducted a statistical clustering analysis (1,2) on a mosaic of VIMS data cubes obtained on February 13, 2010, for Saturn s satellite Mimas. Seven VIMS cubes were geometrically projected and re-sampled to a common spatial resolution. The clustering technique consists of a partitioning algorithm coupled to a criterion that prevents sub-optimal solutions and tests for the influence of random noise in the measurements. The clustering technique is agnostic about the meaning of the clusters, and scientific interpretation requires their a posteriori evaluation. The preliminary results yielded five clusters, demonstrating that spectral variability across Mimas surface is statistically significant. The ratios of the means calculated for each of the clusters show structure within the 1.6- micron water ice band, as well as the shape and the central wavelength of the strong ice band at 2 micron, that map spatially in patterns apparently related to the topography of Mimas, in particular certain regions in and around Herschel crater. The mean spectra of the five clusters, show similarities with laboratory spectra of amorphous and crystalline H2O ice (3) that are suggestive of the presence of an amorphous ice component in certain regions of Mimas, notably on the central peak of Herschel, on the crater floor, and in faults surrounding the crater. This may represent a mixture of both ice phases, or perhaps a layer of amorphous ice on a base of crystalline ice. Another possible occurrence of amorphous ice appears southwest of Herschel, close to the south pole.
- Published
- 2010
24. Astro2020 Activities and Projects White Paper: Arecibo Observatory in the Next Decade
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Roshi, D. Anish, Anderson, L. D., Araya, E., Balser, D., Brisken, W., Brum, C., Campbell, D., Chatterjee, S., Churchwell, E., Condon, J., Cordes, J., Cordova, F., Fernandez, Y., Gago, J., Ghosh, T., Goldsmith, P. F., Heiles, C., Hickson, D., Jeffs, B., Jones, K. M., Lautenbach, J., Lewis, B. M., Lynch, R. S., Manoharan, P. K., Marshall, S., Minchin, R., Palliyaguru, N. T., Perera, B. B. P., Perillat, P., Pinilla-Alonso, N., Pisano, D. J., Quintero, L., Raizada, S., Ransom, S. M., Fernandez-Rodriguez, F. O., Salter, C. J., Santos, P., Sulzer, M., Taylor, P. A., Venditti, F. C. F., Venkataraman, A., Virkki, A. K., Wolszczan, A., Womack, M., and Zambrano-Marin, L. F.
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FOS: Physical sciences ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) - Abstract
The white paper discusses Arecibo Observatory's plan for facility improvements and activities over the next decade. The facility improvements include: (a) improving the telescope surface, pointing and focusing to achieve superb performance up to ~12.5 GHz; (b) equip the telescope with ultrawide-band feeds; (c) upgrade the instrumentation with a 4 GHz bandwidth high dynamic range digital link and a universal backend and (d) augment the VLBI facility by integrating the 12m telescope for phase referencing. These upgrades to the Arecibo telescope are critical to keep the national facility in the forefront of research in radio astronomy while maintaining its dominance in radar studies of near-Earth asteroids, planets and satellites. In the next decade, the Arecibo telescope will play a synergistic role with the upcoming facilities such as ngVLA, SKA and the now commissioned FAST telescope. Further, the observatory will be actively engaged in mentoring and training programs for students from a diverse background., Submitted as an Activities and Projects White Paper for the Astro2020 decadal survey (13 pages, 3 figures, 1 table)
- Published
- 2019
25. Compositional Study of Trans-Neptunian Objects at λ > 2.2μm.
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Fernández-Valenzuela, E., Pinilla-Alonso, N., Stansberry, J., Emery, J. P., Perkins, W., Van Laerhoven, C., Gladman, B. J., Fraser, W., Cruikshank, D., Lellouch, E., Müller, T. G., Grundy, W. M., Trilling, D., Fernandez, Y., and Ore, C. Dalle
- Published
- 2021
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26. A comparative analysis of the outer-belt primitive families.
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De Prá, M. N., Pinilla-Alonso, N., Carvano, J., Licandro, J., Morate, D., Lorenzi, V., de León, J., Campins, H., and Mothé-Diniz, T.
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- *
ASTEROIDS , *SOLAR system , *VISIBLE spectra , *FAMILIES , *COMPARATIVE studies , *PLANETARY systems - Abstract
Context. Asteroid families are witnesses to the intense collisional evolution that occurred on the asteroid belt. The study of the physical properties of family members can provide important information about the state of differentiation of the parent body and provide insights into how these objects were formed. Several of these asteroid families identified across the main belt are dominated by low-albedo, primitive asteroids. These objects are important for the study of Solar System formation because they were subject to weaker thermophysical processing and provide information about the early conditions of our planetary system. Aims. We aim to study the diversity of physical properties among the Themis, Hygiea, Ursula, Veritas, and Lixiaohua families. Methods. We present new spectroscopic data, combined with a comprehensive analysis using a variety of data available in the literature, such as albedo and rotational properties. Results. Our results show that Themis and Hygiea families, the largest families in the region, present similar levels of hydration. Ursula and Lixiaohua families are redder in comparison to the others and present no sign of hydrated members based on the analysis of visible spectra. Conversely, Veritas presents the highest fraction of hydrated members. Conclusions. This work demonstrates a diverse scenario in terms of the physical properties of primitive outer-belt families, which could be associated with dynamical mixing of asteroid populations and the level of differentiation of the parental body. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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27. The spectrum of Pluto, 0.40–0.93 μ m
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Lorenzi, V., Pinilla-Alonso, N., Licandro, J., Cruikshank, D., Grundy, W., Binzel, R., Emery, J., Sciences pour l'environnement (SPE), Université Pascal Paoli (UPP)-Centre National de la Recherche Scientifique (CNRS), Instituto de Astrofisica de Canarias (IAC), Lowell Observatory [Flagstaff], Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Pascal Paoli (UPP), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)
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[PHYS]Physics [physics] ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2016
28. Compositional characterization of V-type candidate asteroids identified using the MOVIS catalogue.
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Medeiros, H, de León, J, Lazzaro, D, Popescu, M, Lorenzi, V, Pinilla-Alonso, N, Landsman, Z, Rizos, J L, and Morate, D
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OPTICAL telescopes ,ASTEROIDS ,VISIBLE spectra ,METEORITES ,CATALOGS ,TELESCOPES - Abstract
The main objective of this work is to compositionally analyse the visible to near-infrared spectra of a total of six V-type candidates identified using the MOVIS (Y - J) versus (J - Ks) colour–colour plot and located outside the Vesta collisional family. We obtained visible and near-infrared spectra of these asteroids using the 2.54m Isaac Newton Telescope, the 2.5m Nordic Optical Telescope, and the 3.58m Telescopio Nazionale Galileo, all located at the El Roque de Los Muchachos Observatory (La Palma, Spain), as well as the 3.0m NASA Infrared Telescope Facility, located at the Mauna Kea Observatory in Hawaii. We computed several diagnostic spectral parameters (slopes, band centres, band depths, band area ratio, or BAR) and compared them to the ones known for HED meteorites and (4) Vesta. The taxonomic classification confirmed five out of the six candidates as V-types, leading to an identification success rate about 83 per cent. In general, the spectral parameters obtained for the five V-types are in good agreement with those of HED meteorites and (4) Vesta. The exception is asteroid (2452) Lyot, a V-type in the outer belt, located very close to (1459) Magnya, but showing distinct [Wo] and [Fs] molar contents both from Magnya and Vesta, pointing toward a diogenitic compostion. We also studied the dependency of the BAR parameter on the way it is computed (removing or not the continuum), the spectral slope, and the last point used to delimit the right wing of the absorption band at 2 μm. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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29. A Herschel-PACS view of 16 Centaurs
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Duffard, Rene, Pinilla-Alonso, N., Santos-Sanz, P., Vilenius, E., Ortiz, J., Mueller, T., Fornasier, S., Lellouch, E., Mommert, M., Pal, A., Kiss, C., Mueller, M., Stansberry, J., Delsanti, A., Peixinho, N., and Astronomy
- Abstract
The goal of this work is to characterize a set of Centaurs in terms of their size, albedo, and thermal properties. The Herschel open time key program "TNOs are Cool!'' observed 130 Centaurs and TNOs in 2009-2012. In this particular work we use Herschel/PACS three-band photometry to obtain monochromatic flux densities at 70, 100 and 160 μm. Additionally, we also incorporate Spitzer/MIPS flux densities at 24 and 70 μm when available. We use a consistent method for data reduction and aperture photometry to finally determine sizes and albedos of 16 Centaurs using radiometric techniques. We study the correlations between the size and albedo resulting from our models and other physical (i.e spectral slope) and orbital parameters using a more extended sample (obtained from literature). The final sample comprises 36 objects: 18 Centaurs observed with Herschel/PACS; 10 observed only with Spitzer and 8 SDOs. The first conclusion is that the albedo of the Centaurs is not determined by their orbit. Similarly we do not find any correlation between diameter and orbital parameters. We also find that most of the objects in our sample are dark (pv
- Published
- 2013
30. Precise reflectante spectra of ordinary chondrites in the visible and uv : exploring the variability of s-class asteroidal spectra
- Author
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Trigo Rodríguez, Josep María, Llorca, Jordi, Madiedo Gil, José María, Rivkin, A. S., León, J. de, and Pinilla Alonso, N.
- Abstract
Narrow-band spectrophotometry programs for the study of asteroids were initiated in the 1960s [1,2], which were able to identify clear absorption bands in the UV and visible, that were used later on in order to develop the first asteroid taxonomy [3]. A step forward was to remotely obtain reflectance spectra of asteroids to establish the existence of families [4, 5, 6], and to place meteorites broadly within these families based on their own spectra. This approach is imperfect due to space weathering, that together with the presence of regolith, intrinsic roughness, etc., alters the reflectance spectra to be compared with spectra of meteorites in our laboratories. Currently there are several comprehensive spectral catalogue of meteorites [7-8], but we wish to explore the capacities of current spectrographs to obtain reflectivities in those extreme regions of the electromagnetic spectrum where data is poor (typically below 0.4 microns and over 2.4 microns). Additionally we wish to explore the importance of roughness as the reason for the diverse mineralogy observed for S-class asteroids that are linked to the ordinary chondrites [9].
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- 2011
31. Mimas: Preliminary Evidence For Amorphous Water Ice From VIMS
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Cruikshank, Dale P., Marzo, G., Pinilla-Alonso, N., Roush, T. L., Mastrapa, R. M., Dalle Ore, C. M., Buratti, B. J., Stephan, Katrin, Brown, R.H., Baines, K. H., Clark, R. N., Nicholson, P.D., and Sotin, C.
- Subjects
Planetengeologie ,Mimas ,VIMS ,Cassini - Published
- 2010
32. Differences between the Pallas collisional family and similarly sized B-type asteroids.
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Alí-Lagoa, V., Licandro, J., Gil-Hutton, R., Cañada-Assandri, M., Delbo, M., de León, J., Campins, H., Pinilla-Alonso, N., Kelley, M. S. P., and Hanuš, J.
- Subjects
PALLAS (Asteroid) ,ALBEDO ,REFLECTANCE spectroscopy ,INFRARED spectra ,PLANETARY systems - Abstract
Context. B-type asteroids constitute a peculiar spectral class within the C-complex. Previous work has pointed out the difference between the visible geometric albedos of B-types and those of the Pallas collisional family (PCF), whose few members with observed spectra are B-types (one exception out of eight objects). This has been interpreted as being due to compositional differences. However, the PCF members are typically smaller than the spectroscopically classified B-types, and the following possibilities have not been ruled out: the albedo differences might be related to a size-albedo dependence and/or to the generally larger errors of the WISE data and best-fitting values of the derived parameters expected for smaller objects. Aims. We compare albedos and beaming parameters of PCF members and B-types of similar sizes and re-examine our conclusion on the different composition of the PCF. Methods. By modelling their WISE/NEOWISE data, we derived sizes and albedos of all objects whose Sloan Digital Sky Survey reflectances are similar to the typical B-type reflectance spectra. In particular, we derived the so-called infrared beaming parameters (η), effective diameters (D), and corresponding visible geometric albedos (pV), and studied their value distributions. Results. We obtained the effective diameter and geometric visible albedo for ~600 B-type asteroids whose sizes range between 2 and 100 km, approximately half of which have fitted η-values that are inversely correlated to size. We found that the albedo distributions of the PCF is significantly different from that of other B-types in the same size range (2-20 km), and we rule out any size-albedo dependency or biases related to the lower quality of the pV-values of smaller objects. In addition, we also found differences between the η-value distribution of the PCF and the other similarly-sized B-types. Conclusions. The differences in the visible albedos of PCF members and the other B-types of similar sizes is a strong indication that their compositions are different. The trend between beaming parameter and size of the B-types (excluding the PCF) is consistent with the expectation that the surfaces of smaller asteroids have coarser rocks than do those of larger objects (D > 40 km), which are thought to be covered by a finer, more insulating layer of dust. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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33. Depth of a strong jovian jet from a planetary-scale disturbance driven by storms
- Author
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Sanchez-Lavega, A., Orton, G.S., Hueso, R., Garcia-Melendo, E., Perez-Hoyos, S., Simon-Miller, A., Rojas, J.F., Gomez, J.M., Yanamandra-Fisher, P., Fletcher, L., Joels, J., Kemerer, J., Hora, J., Karkoschka, E., de Pater, I., Wong, M.H., Marcus, P.S., Pinilla-Alonso, N., Carvalho, F., Go, C., Parker, D., Salway, M., Valimberti, M., and Pujic, Z.
- Subjects
Environmental issues ,Science and technology ,Zoology and wildlife conservation - Abstract
Nature 451, 437-440 (2008) In Fig. 3a, the descriptions of the continuous and dotted curves were inadvertently swapped. The continuous line corresponds to the modified synthetic thermal profile (storms reaching [...]
- Published
- 2007
34. Rotationally resolved spectroscopy of dwarf planet (136472) Makemake.
- Author
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Lorenzi, V., Pinilla-Alonso, N., and Licandro, J.
- Subjects
- *
DWARF planets , *ASTRONOMICAL spectroscopy , *SOLAR system , *ORGANIC compounds , *KUIPER belt , *METHANE hydrates - Abstract
Context. Icy dwarf planets are key for studying the chemical and physical states of ices in the outer solar system. The study of secular and rotational variations gives us hints of the processes that contribute to the evolution of their surface. Aims. The aim of this work is to search for rotational variability on the surface composition of the dwarf planet (136472) Makemake Methods. We observed Makemake in April 2008 with the medium-resolution spectrograph ISIS, at the William Herschel Telescope (La Palma, Spain) and obtained a set of spectra in the 0.28-0.52 μm and 0.70-0.95 μm ranges, covering 82% of its rotational period. For the rotational analysis, we organized the spectra in four different sets corresponding to different rotational phases, and after discarding one with low signal to noise, we analyzed three of them that cover 71% of the surface. For these spectra we computed the spectral slope and compared the observed spectral bands of methane ice with reflectances of pure methane ice to search for shifts of the center of the bands, related to the presence of CH4/N2 solid solution. Results. All the spectra have a red color with spectral slopes between 20%/1000 Å and 32%/1000 Å in accordance with previously reported values. Some variation in the spectral slope is detected, pointing to the possibility of a variation in the surface content or the particle size of the solid organic compound. The absorption bands of methane ice present a shift toward shorter wavelengths, indicating that methane (at least partially) is in solid solution with nitrogen. There is no variation within the errors of the shifts with the wavelength or with the depth of the bands, so there is no evidence of variation in the CH4/N2 mixing ratio with rotation. By comparing with all the available data in the literature, no secular compositional variations between 2005 and 2008 is found. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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35. Precipitable water vapour content above the Roque de los Muchachos Observatory from GPS estimations.
- Author
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García-Lorenzo, B., Castro-Almazán, J. A., Eff-Darwich, A., Muñoz-Tuñón, C., Pinilla-Alonso, N., Rodriguez-Espinosa, J. M., and Romero, I.
- Published
- 2009
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36. Photometric and spectroscopic evidence for a dense ring system around Centaur Chariklo.
- Author
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Duffard, R., Pinilla-Alonso, N., Ortiz, J. L., Alvarez-Candal, A., Sicardy, B., Santos-Sanz, P., Morales, N., Colazo, C., Fernández-Valenzuela, E., and Braga-Ribas, F.
- Subjects
- *
STELLAR photometry , *NEAR infrared radiation , *LIGHT scattering , *STELLAR magnitudes , *KUIPER belt - Abstract
Context. A stellar occultation observed on 3rd June 2013 revealed the presence of two dense and narrow rings separated by a small gap around the Centaur object (10 199) Chariklo. The composition of these rings is not known. We suspect that water ice is present in the rings, as is the case for Saturn and other rings around the giant planets. Aims. In this work, we aim to determine if the variability in the absolute magnitude of Chariklo and the temporal variation of the spectral ice feature, even when it disappeared in 2007, can be explained by an icy ring system whose aspect angle changes with time. Methods. We explained the variations on the absolute magnitude of Chariklo and its ring by modeling the light reflected by a system as the one described above. Using X-shooter at VLT, we obtained a new reflectance spectra. We compared this new set of data with the ones available in the literature. We showed how the water ice feature is visible in 2013 in accordance with the ring configuration, which had an opening angle of nearly 34° in 2013. Finally, we also used models of light scattering to fit the visible and near-infrared spectra that shows different characteristics to obtain information on the composition of Chariklo and its rings. Results. We showed that absolute photometry of Chariklo from the literature and new photometric data that we obtained in 2013 can be explained by a ring of particles whose opening angle changes as a function of time. We used the two possible pole solutions for the ring system and found that only one of them, α = 151.30 ± 0.5, δ = 41.48 ± 0.2° (λ = 137.9 ± 0.5,β = 27.7 ± 0.2°), provides the right variation of the aspect angle with time to explain the photometry, whereas the other possible pole solution fails to explain the photometry. From spectral modeling, we derived the composition of the Chariklo surface and that of the rings using the result on the pole solution. Chariklo surface is composed with about 60% of amorphous carbon, 30% of silicates and 10% of organics; no water ice was found on the surface. The ring, on the other hand, contains 20% of water ice, 40-70% of silicates, and 10-30% of tholins and small quantities of amorphous carbon. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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37. "TNOs are Cool": A survey of the trans-Neptunian region XI. A Herschel-PACS view of 16 Centaurs.
- Author
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Duffard, R., Pinilla-Alonso, N., Santos-Sanz, P., Vilenius, E., Ortiz, J. L., Mueller, T., Fornasier, S., Lellouch, E., Mommert, M., Pal, A., Kiss, C., Mueller, M., Stansberry, J., Delsanti, A., Peixinho, N., and Trilling, D.
- Subjects
- *
KUIPER belt , *CENTAUR objects , *ALBEDO , *ASTROPHYSICAL radiation , *PHOTOMETRY - Abstract
Context. Centaurs are the transitional population between trans-Neptunian objects (TNOs) and Jupiter-family comets. Their physical properties provide an insight into TNO properties, but only under restricted conditions since Centaurs are closer to the Sun and Earth. For this reason it is possible to access the smaller ones, which is more difficult to do with the TNO population. Aims. The goal of this work is to characterize a set of 16 Centaurs in terms of their size, albedo, and thermal properties. We study the correlations, for a more extended sample obtained from the literature, of diameter, albedo, orbital parameters, and spectral slopes. Methods. We performed three-band photometric observations using Herschel-PACS and used a consistent method for the data reduction and aperture photometry of this sample to obtain monochromatic flux densities at 70, 100, and 160 μm. Additionally, we used Spitzer-MIPS flux densities at 24 and 70 μm when available. We also included in our Centaur sample scattered disk objects, a dynamical family of TNOs, using results previously published by our team, and some Centaurs observed only with the Spitzer-MIPS instrument. Results. We have determined new radiometric sizes and albedos of 16 Centaurs. The first conclusion is that the albedos of Centaur objects are not correlated with their orbital parameters. Similarly, there is no correlation between diameter and orbital parameters. Most of the objects in our sample are dark (pv < 7%) and most of them are small (D < 120 km). However, there is no correlation between albedo and diameter, in particular for the group of small objects as albedo values are homogeneously distributed between 4 to 16%. The correlation with the color of the objects showed that red objects are all small (mean diameter 65 km), while the gray ones span a wide range of sizes (mean diameter 120 km). Moreover, the gray objects tend to be darker, with a mean albedo of 5.6%, compared with a mean of 8.5% (ranging from 5 to 15%) for the red objects. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
38. Rotationally resolved spectroscopy of (20000) Varuna in the near-infrared.
- Author
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Lorenzi, V., Pinilla-Alonso, N., Licandro, J., Ore, C. M. Dalle, and Emery, J. P.
- Subjects
- *
CENTAUR objects , *TEMPERATURE of stars , *NEAR infrared spectroscopy , *TRANS-Neptunian objects , *NATURAL satellites , *RADIATIVE transfer , *ASTRONOMICAL observations - Abstract
Context. Models of the escape and retention of volatiles by minor icy objects exclude any presence of volatile ices on the surface of trans-Neptunian objects (TNOs) smaller than ~1000 km in diameter at the typical temperature in this region of the solar system, whereas the same models show that water ice is stable on the surface of objects over a wide range of diameters. Collisions and cometary activity have been used to explain the process of surface refreshing of TNOs and Centaurs. These processes can produce surface heterogeneity that can be studied by collecting information at different rotational phases. Aims. The aims of this work are to study the surface composition of (20000) Varuna, a TNO with a diameter 668+154 -86 km and to search for indications of rotational variability. Methods. We observed (20000) Varuna during two consecutive nights in January 2011 with the near-infrared camera and spectrometer NICS at the Telescopio Nazionale Galileo, La Palma, Spain.We used the low resolution mode with the AMICI prism to obtain a set of spectra covering the whole rotation period of the Varuna (Pr = 6.34 h). We fit the resulting relative reflectance with radiative transfer models of the surface of atmosphereless bodies. Results. After studying the spectra corresponding to different rotational phases of Varuna, we did not find any indication of surface variability at 2σ level. In all the spectra, we detect an absorption at 2.0 μm, suggesting the presence of water ice on the surface. We do not detect any other volatiles on the surface, although the signal-to-noise ratio is not high enough to discard their presence in small quantities. Based on scattering models, we present two possible compositions compatible with our set of data and discuss their implications in the framework of the collisional history of the trans-Neptunian belt. Conclusions. We find that the most probable composition for the surface of Varuna is a mixture of amorphous silicates, complex organics, and water ice. This composition is compatible with all the materials being primordial, so no replenishment mechanism is needed in the equation. However, our data can also be fitted by models containing up to a 10% of methane ice. For an object with the characteristics of Varuna, this volatile could not be primordial, so an event, such as an energetic impact, would be needed to explain its presence on the surface. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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39. Additional spectra of asteroid 1996 FG3, backup target of the ESA MarcoPolo-R mission.
- Author
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de León, J., Lorenzi, V., Alí-Lagoa, V., Licandro, J., Pinilla-Alonso, N., and Campins, H.
- Subjects
NEAR-earth asteroids ,SPACE flight ,NEAR infrared spectroscopy - Abstract
Context. Near-Earth binary asteroid (175706) 1996 FG
3 is the current backup target of the ESA MarcoPolo-R mission, selected for the study phase of ESA M3 missions. It is a primitive (C-type) asteroid that shows significant variation in its visible and near-infrared spectra. Aims. Here we present new visible and near-infrared spectra of 1996 FG3 . We compare our new data with other published spectra, analysing the variation in the spectral slope. The asteroid will not be observable again over the next three years at least. Methods. We obtained visible and near-infrared spectra using DOLORES and NICS instruments, respectively, at the Telescopio Nazionale Galileo (TNG), a 3.6 m telescope located at El Roque de los Muchachos Observatory in La Palma, Spain. To compare with other published spectra of the asteroid, we computed the spectral slope S′, and studied any plausible correlation of this quantity with the phase angle (α). Results. In the case of visible spectra, we find a variation in spectral slope of ΔS′ = 0.15 ± 0.10%/10³ Å/° for 3° < α < 18°, which is in good agreement with the values found in the literature for the phase reddening effect. In the case of the near-infrared, there seems to be a trend between the reddening of the spectra and the phase angle, excluding one point. We find a variation in the slope of ΔS′ = 0.04 ± 0.08%/10³ Å/° for 6° < α < 51°. Our computed variation in S′ is in good agreement with the only two values found in the literature for the phase reddening in the near-infrared. Conclusions. The variation in the spectral slope of asteroid 1996 FG3 shows a trend with the phase angle at the time of the observations, both in the visible and the near-infrared. It is worth noting that, to fully explain this spectral variability we should take into account other factors, like the position of the secondary component of the binary asteroid 1999 FG3 with respect to the primary, or the spin axis orientation at the time of the observations. More data are necessary for an analysis of this kind. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
40. Surface composition and dynamical evolution of two retrograde objects in the outer solar system: 2008 YB3 and 2005 VD.
- Author
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Pinilla-Alonso, N., Alvarez-Candal1, A., Melita, M. D., Lorenzi, V., Licandro, J., Carvano, J., Lazzaro, D., Carraro, G., Alí-Lagoa, V., Costa, E., and Hasselmann, P. H.
- Subjects
- *
INTERSTELLAR medium , *TRANS-Neptunian objects , *SOLAR system , *SATURN (Planet) , *KUIPER belt - Abstract
Most of the objects in the trans-Neptunian belt (TNb) and related populations move in prograde orbits with low eccentricity and inclination. However, the list of icy minor bodies moving in orbits with an inclination above 408 has increased in recent years. The origin of these bodies, and in particular of those objects in retrograde orbits, is not well determined, and different scenarios are considered, depending on their inclination and perihelion. In this paper, we present new observational and dynamical data of two objects in retrograde orbits, 2008 YB3 and 2005 VD.We find that the surface of these extreme objects is depleted of ices and does not contain the "ultra-red" matter typical of some Centaurs. Despite small differences, these objects share common colors and spectral characteristics with the Trojans, comet nuclei, and the group of grey Centaurs. All of these populations are supposed to be covered by a mantle of dust responsible for their reddish-to-neutral color. To investigate if the surface properties and dynamical evolution of these bodies are related, we integrate their orbits for 108 years to the past. We find a remarkable difference in their dynamical evolutions: 2005 VD's evolution is dominated by a Kozai resonance with planet Jupiter while that of 2008 YB3 is dominated by close encounters with planets Jupiter and Saturn. Our models suggest that the immediate site of provenance of 2005 VD is the in the Oort Cloud, whereas for 2008 YB3 it is in the trans-Neptunian region. Additionally, the study of their residence time shows that 2005 VD has spent a larger lapse of time moving in orbits in the region of the giant planets than 2008 YB3. Together with the small differences in color between these two objects, with 2005 VD being more neutral than 2008 YB3, this fact suggests that the surface of 2005 VD has suffered a higher degree of processing, which is probably related to cometary activity episodes. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
41. Infrared astronomical characteristics of the Roque de los Muchachos Observatory: precipitable water vapour statistics.
- Author
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García-Lorenzo, B., Eff-Darwich, A., Castro-Almazán, J., Pinilla-Alonso, N., Muñoz-Tuñón, C., and Rodríguez-Espinosa, J. M.
- Subjects
ATMOSPHERIC water vapor ,GLOBAL Positioning System ,ARTIFICIAL satellites ,INFRARED astronomy ,STATISTICS - Abstract
We present measurements of the atmospheric water vapour content above the Roque de los Muchachos Observatory (ORM) obtained using the Global Positioning System (GPS). The GPS measurements have been evaluated by comparison with 940-nm radiometer observations. A statistical analysis of the GPS measurements points to the ORM as an observing site with suitable conditions for infrared observations, with a median column of precipitable water vapour (PWV) of 3.8 mm. PWV presents a clear seasonal behaviour, with winter and spring being the best seasons for infrared observations. The percentage of nights showing PWV values less than 3 mm is over 60 per cent in February, March and April. We have also estimated the temporal variability of water vapour content at the ORM. We present a summary of PWV statistical results at different astronomical sites, noting that these values are not directly comparable as a result of the differences in the techniques used to recorded the data. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
42. Near-infrared spectroscopy of 1999 JU3, the target of the Hayabusa 2 mission.
- Author
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Pinilla-Alonso, N., Lorenzi, V., Campins, H., de Leon, J., and Licandro, J.
- Subjects
- *
ASTEROIDS , *INFRARED spectroscopy , *NEAR-earth asteroids -- Exploration - Abstract
Context. Primitive asteroids contain complex organic material and ices relevant to the origin of life on Earth. These types of asteroids are the target of several sample-return missions to be launched in the next years. 1999 JU3 is the target of the Japanese Aerospace Exploration Agency's Hayabusa 2 mission. Aims. 1999 JU3 has been previously identified as a C-class asteroid. Spectroscopic observations at longer wavelengths will help to constrain its composition. Methods. We obtained spectroscopy of 1999 JU3 from 0.85 to 2.2 μm, with the 3.6 m Telescopio Nazionale Galileo using the low-resolution mode of the Near Infrared Camera Spectrograph. Results. We present a near-infrared spectrum of 1999 JU3 from 0.85 to 2.2 μ that is consistent with previously published spectra and with its C-type classification. Conclusions. Our spectrum confirms the primitive nature of 1999 JU3 and its interest as target of the sample-return mission Hayabusa 2. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
43. Detection of carbon dioxide and hydrogen peroxide on the stratified surface of Charon with JWST.
- Author
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Protopapa S, Raut U, Wong I, Stansberry J, Villanueva GL, Cook J, Holler B, Grundy WM, Brunetto R, Cartwright RJ, Mamo B, Emery JP, Parker AH, Guilbert-Lepoutre A, Pinilla-Alonso N, Milam SN, and Hammel HB
- Abstract
Charon, Pluto's largest moon, has been extensively studied, with research focusing on its primitive composition and changes due to radiation and photolysis. However, spectral data have so far been limited to wavelengths below 2.5 μm, leaving key aspects unresolved. Here we present the detection of carbon dioxide (CO
2 ) and hydrogen peroxide (H2 O2 ) on the surface of Charon's northern hemisphere, using JWST data. These detections add to the known chemical inventory that includes crystalline water ice, ammonia-bearing species, and tholin-like darkening constituents previously revealed by ground- and space-based observations. The H2 O2 presence indicates active radiolytic/photolytic processing of the water ice-rich surface by solar ultraviolet and interplanetary medium Lyman-α photons, solar wind, and galactic cosmic rays. Through spectral modeling of the surface, we show that the CO2 is present in pure crystalline form and, possibly, in intimately mixed states on the surface. Endogenically sourced subsurface CO2 exposed on the surface is likely the primary source of this component, with possible contributions from irradiation of hydrocarbons mixed with water ice, interfacial radiolysis between carbon deposits and water ice, and the implantation of energetic carbon ions from the solar wind and solar energetic particles., (© 2024. The Author(s).)- Published
- 2024
- Full Text
- View/download PDF
44. Lunar Lithium-7 Sensing ( δ 7Li): Spectral Patterns and Artificial Intelligence Techniques.
- Author
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Fernandez J, Fernandez S, Diez E, Pinilla-Alonso N, Pérez S, Iglesias S, Buendía A, Rodríguez J, and de Cos J
- Abstract
Lithium, a critical natural resource integral to modern technology, has influenced diverse industries since its discovery in the 1950s. Of particular interest is lithium-7, the most prevalent lithium isotope on Earth, playing a vital role in applications such as batteries, metal alloys, medicine, and nuclear research. However, its extraction presents significant environmental and logistical challenges. This article explores the potential for lithium exploration on the Moon, driven by its value as a resource and the prospect of cost reduction due to the Moon's lower gravity, which holds promise for future space exploration endeavors. Additionally, the presence of lithium in the solar wind and its implications for material transport across celestial bodies are subjects of intrigue. Drawing from a limited dataset collected during the Apollo missions (Apollo 12, 15, 16, and 17) and leveraging artificial intelligence techniques and sample expansion through bootstrapping, this study develops predictive models for lithium-7 concentration based on spectral patterns. The study areas encompass the Aitken crater, Hadley Rima, and the Taurus-Littrow Valley, where higher lithium concentrations are observed in basaltic lunar regions. This research bridges lunar geology and the formation of the solar system, providing valuable insights into celestial resources and enhancing our understanding of space. The data used in this study were obtained from the imaging sensors (infrared, visible, and ultraviolet) of the Clementine satellite, which significantly contributed to the success of our research. Furthermore, the study addresses various aspects related to statistical analysis, sample quality validation, resampling, and bootstrapping. Supervised machine learning model training and validation, as well as data import and export, were explored. The analysis of data generated by the Clementine probe in the near-infrared (NIR) and ultraviolet-visible (UVVIS) spectra revealed evidence of the presence of lithium-7 (Li-7) on the lunar surface. The distribution of Li-7 on the lunar surface is non-uniform, with varying concentrations in different regions of the Moon identified, supporting the initial hypothesis associating surface Li-7 concentration with exposure to solar wind. While a direct numerical relationship between lunar topography and Li-7 concentration has not been established due to morphological diversity and methodological limitations, preliminary results suggest significant economic and technological potential in lunar lithium exploration and extraction.
- Published
- 2024
- Full Text
- View/download PDF
45. Water ice and organics on the surface of the asteroid 24 Themis.
- Author
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Campins H, Hargrove K, Pinilla-Alonso N, Howell ES, Kelley MS, Licandro J, Mothé-Diniz T, Fernández Y, and Ziffer J
- Subjects
- Extraterrestrial Environment chemistry, Ice analysis, Minor Planets, Organic Chemicals analysis
- Abstract
It has been suggested that Earth's current supply of water was delivered by asteroids, some time after the collision that produced the Moon (which would have vaporized any of the pre-existing water). So far, no measurements of water ice on asteroids have been made, but its presence has been inferred from the comet-like activity of several small asteroids, including two members of the Themis dynamical family. Here we report infrared spectra of the asteroid 24 Themis which show that ice and organic compounds are not only present on its surface but also prevalent. Infrared spectral differences between it and other asteroids make 24 Themis unique so far, and our identification of ice and organics agrees with independent results that rule out other compounds as possible sources of the observed spectral structure. The widespread presence of surface ice on 24 Themis is somewhat unexpected because of the relatively short lifetime of exposed ice at this distance ( approximately 3.2 au) from the Sun. Nevertheless, there are several plausible sources, such as a subsurface reservoir that brings water to the surface through 'impact gardening' and/or sublimation.
- Published
- 2010
- Full Text
- View/download PDF
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