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246 results on '"Stansberry, J. A."'

201. Optimized Herschel/PACS photometer observing and data reduction strategies for moving solar system targets.

Author

Kiss, C., Müller, T., Vilenius, E., Pál, A., Santos-Sanz, P., Lellouch, E., Marton, G., Verebélyi, E., Szalai, N., Hartogh, P., Stansberry, J., Henry, F., and Delsanti, A.

Subjects
DATA reduction, PHOTODETECTORS, ASTRONOMICAL photometry, ASTRONOMICAL observations, SOLAR system, ASTRONOMICAL spectroscopy
Abstract

The 'TNOs are Cool!: A survey of the trans-Neptunian region' is a Herschel Open Time Key Program that aims to characterize planetary bodies at the outskirts of the Solar System using PACS and SPIRE data, mostly taken as scan-maps. In this paper we summarize our PACS data reduction scheme that uses a modified version of the standard pipeline for basic data reduction, optimized for faint, moving targets. Due to the low flux density of our targets the observations are confusion noise limited or at least often affected by bright nearby background sources at 100 and 160 $\mu $m. To overcome these problems we developed techniques to characterize and eliminate the background at the positions of our targets and a background matching technique to compensate for pointing errors. We derive a variety of maps as science data products that are used depending on the source flux and background levels and the scientific purpose. Our techniques are also applicable to a wealth of other Herschel solar system photometric observations, e.g. comets and near-Earth asteroids. The principles of our observing strategies and reduction techniques for moving targets will also be applicable for similar surveys of future infrared space projects. [ABSTRACT FROM AUTHOR]

Published
2014
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205. "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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208. A cGMP-dependent protein kinase is implicated in wild-type motility in C. elegans.

Author

Stansberry, J., Baude, E.J., Taylor, M.K., Chen, P-J., Jin, S-W., Ellis, R.E., and Uhler, M.D.

Subjects
*PROTEIN kinases, *CAENORHABDITIS elegans
Abstract

In mammals, cyclic GMP and cGMP-dependent protein kinases (cGKs) have been implicated in the regulation of many neuronal functions including long-term potentiation and long-term depression of synaptic efficacy. To develop Caenorhabditis elegans as a model system for studying the neuronal function of the cGKs, we cloned and characterized the cgk-1 gene. A combination of approaches showed that cgk-1 produces three transcripts, which differ in their first exon but are similar in length. Northern analysis of C. elegans RNA, performed with a probe designed to hybridize to all three transcripts, confirmed that a major 3.0 kb cgk-1 transcript is present at all stages of development. To determine if the CGK-1C protein was a cGMP-dependent protein kinase, CGK-1C was expressed in Sf9 cells and purified. CGK-1C shows a K[sub a] of 190 ± 14 nm for cGMP and 18.4 ± 2 µm for cAMP. Furthermore, CGK-1C undergoes autophosphorylation in a cGMP-dependent manner and is inhibited by the commonly used cGK inhibitor, KT5823. To determine which cells expressed CGK-1C, a 2.4-kb DNA fragment from the promoter of CGK-1C was used to drive GFP expression. The CGK-1C reporter construct is strongly expressed in the ventral nerve cord and in several other neurons as well as the marginal cells of the pharynx and intestine. Finally, RNA-mediated interference of CGK-1 resulted in movement defects in nematode larvae. These results provide the first demonstration that cGMP-dependent protein kinase is present in neurons of C.elegans and show that this kinase is required for normal motility. [ABSTRACT FROM AUTHOR]

Published
2001
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209. Absolute Calibration and Characterization of the Multiband Imaging Photometer for Spitzer. I. The Stellar Calibrator Sample and the 24 ?m Calibration

Author

Engelbracht, C. W., Blaylock, M., Su, K. Y. L., Rho, J., Rieke, G. H., Muzerolle, J., Padgett, D. L., Hines, D. C., Gordon, K. D., Fadda, D., Noriega-Crespo, A., Kelly, D. M., Latter, W. B., Hinz, J. L., Misselt, K. A., Morrison, J. E., Stansberry, J. A., Shupe, D. L., Stolovy, S., Wheaton, Wm. A., Young, E. T., Neugebauer, G., Wachter, S., Pérez-González, P. G., Frayer, D. T., and Marleau, F. R.

Abstract

We present the stellar calibrator sample and the conversion from instrumental to physical units for the 24 ?m channel of the Multiband Imaging Photometer for Spitzer(MIPS). The primary calibrators are A stars, and the calibration factor based on those stars is 4.54 × 10-2MJy sr?1(DN s?1)?1, with a nominal uncertainty of 2%. We discuss the data reduction procedures required to attain this accuracy; without these procedures, the calibration factor obtained using the automated pipeline at the SpitzerScience Center is 1.6% ± 0.6% lower. We extend this work to predict 24 ?m flux densities for a sample of 238 stars that covers a larger range of flux densities and spectral types. We present a total of 348 measurements of 141 stars at 24 ?m. This sample covers a factor of ?460 in 24 ?m flux density, from 8.6 mJy up to 4.0 Jy. We show that the calibration is linear over that range with respect to target flux and background level. The calibration is based on observations made using 3 s exposures; a preliminary analysis shows that the calibration factor may be 1% and 2% lower for 10 and 30 s exposures, respectively. We also demonstrate that the calibration is very stable: over the course of the mission, repeated measurements of our routine calibrator, HD 159330, show a rms scatter of only 0.4%. Finally, we show that the point-spread function (PSF) is well measured and allows us to calibrate extended sources accurately; Infrared Astronomy Satellite(IRAS) and MIPS measurements of a sample of nearby galaxies are identical within the uncertainties.

Published
2007
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210. Absolute Calibration and Characterization of the Multiband Imaging Photometer for Spitzer. III. An Asteroid-based Calibration of MIPS at 160 ?m

Author

Stansberry, J. A., Gordon, K. D., Bhattacharya, B., Engelbracht, C. W., Rieke, G. H., Marleau, F. R., Fadda, D., Frayer, D. T., Noriega-Crespo, A., Wachter, S., Young, E. T., Müller, T. G., Kelly, D. M., Blaylock, M., Henderson, D., Neugebauer, G., Beeman, J. W., and Haller, E. E.

Abstract

We describe the absolute calibration of the Multiband Imaging Photometer for Spitzer(MIPS) 160 ?m channel. After the on-orbit discovery of a near-IR ghost image that dominates the signal for sources hotter than about 2000 K, we adopted a strategy utilizing asteroids to transfer the absolute calibrations of the MIPS 24 and 70 ?m channels to the 160 ?m channel. Near-simultaneous observations at all three wavelengths are taken, and photometry at the two shorter wavelengths is fit using the standard thermal model. The 160 ?m flux density is predicted from those fits and compared with the observed 160 ?m signal to derive the conversion from instrumental units to surface brightness. The calibration factor we derive is 41.7 MJy sr?1MIPS160?1(MIPS160 being the instrumental units). The scatter in the individual measurements of the calibration factor, as well as an assessment of the external uncertainties inherent in the calibration, lead us to adopt an uncertainty of 5.0 MJy sr?1MIPS160?1(12%) for the absolute uncertainty on the 160 ?m flux density of a particular source as determined from a single measurement. For sources brighter than about 2 Jy, nonlinearity in the response of the 160 ?m detectors produces an underestimate of the flux density: for objects as bright as 4 Jy, measured flux densities are likely to be ?20% too low. This calibration has been checked against that of the ISO(using ULIRGs) and IRAS(using IRAS-derived diameters), and is consistent with those at the 5% level.

Published
2007
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212. Volatile and Climate Cycles on Short and Long Timescales.

Author

Earle, A. M., Binzel, R. P., Young, L. A., Bertrand, T., Buie, M. W., Cruikshank, D. P., Ennico, K. S., Forget, F., Grundy, W. M., Moore, J. M., Olkin, C. B., Schmitt, B., Spencer, J. R., Stansberry, J. A., Stern, S. A., Trafton, L. M., Umurhan, O. M., and Weaver, H. A.

Subjects
GENERAL circulation model, CLIMATOLOGY
Published
2019

213. Near-Infrared Spectra of Icy Outer Solar System Surfaces: Remote Determination of H2O Ice Temperatures

Author

Grundy, W. M., Buie, M. W., Stansberry, J. A., Spencer, J. R., and Schmitt, B.

Abstract

We present new 1.20 to 2.35 μm spectra of satellites of Jupiter, Saturn, and Uranus, and the rings of Saturn, obtained in 1995 and 1998 at Lowell Observatory. For most of the target objects, our data provide considerable improvement in spectral resolution and signal-to-noise over previously published data. Absorption bands with shapes characteristic of low-temperature, hexagonal crystalline H2O ice dominate the spectra of most of our targets in this wavelength range. We make use of newly published temperature-dependent wavelengths and relative strengths of H2O absorption bands to infer ice temperatures from our spectra. These ice temperatures are distinct from temperatures determined from thermal emission measurements or simulations of radiative balances. Unlike those methods, which average over all terrains including ice-free regions, our temperature-sensing method is only sensitive to the ice component. Our method offers a new constraint which, combined with other observations, can lead to better understanding of thermal properties and textures of remote, icy surfaces. Ice temperatures are generally lower than thermal emission brightness temperatures, indicative of the effects of thermal inertia and segregation between ice and warmer, darker materials. We also present the results of experiments to investigate possible changes of water ice temperature over time, including observations of Titania at two epochs, and of Ganymede and saturnian ring particles following emergence from the eclipse shadows of their primary planets. Finally, we discuss limitations of our temperature measurement method which can result from the presence of H2O in phases other than hexagonal ice-Ih, such as amorphous ice, hydrated mineral phases, or radiation-damaged crystalline ice. Our spectra of Europa and Enceladus exhibit peculiar spectral features which may result from effects such as these.

Published
1999
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214. COMPOSITION OF PLUTO'S SMALL SATELLITES: ANALYSIS OF NEW HORIZONS SPECTRAL IMAGES.

Author

Cook, J. C., Binzel, R. P., Cruikshank, D. P., Ore, C. M. Dalle, Earle, A., Ennico, K., Grundy, W. M., Howett, C., Jennings, D. J., Lunsford, A. W., Olkin, C. B., Parker, A. H., Philippe, S., Protopapa, S., Reuter, D., Schmitt, B., Stansberry, J. A., Stern, S. A., Verbiscer, A., and Weaver, H. A.

Subjects
SATELLITES of Pluto, SPECTRAL imaging
Published
2017

215. MAPPING CHARON AT 2 21 MICRONS.

Author

Cook, J. C., Ore, C. M. Dalle, Binzel, R. P., Cruikshank, D. P., Earle, A., Ennico, K., Grundy, W. M., Howett, C., Jennings, D. J., Lunsford, A. W., Olkin, C. B., Parker, A. H., Philippe, S., Protopapa, S., Reuter, D., Schmitt, B., Stansberry, J. A., Stern, S. A., Verbiscer, A., and Weaver, H. A.

Subjects
CHARON (Satellite), SATELLITES of Pluto, CRYSTALLINITY
Published
2017

216. RULES OF ORDER AND GOVERNMENT.

Author

TURNER, H. M., STANSBERRY, J. P., DICKSON, MOSES, JOHNSON, J. H. A., EMBREY, J. C., CAIN, R. H., and DICKERSON, WILLIAM F

Published
1876

225. 'tNOs are Cool': A survey of the trans-Neptunian region

Author

Müller, T. G., Lellouch, E., Stansberry, J., Kiss, C., Santos-Sanz, P., Vilenius, E., Protopapa, S., Moreno, R., Mueller, M., Delsanti, A., Rene Duffard, Fornasier, S., Groussin, O., Harris, A. W., Henry, F., Horner, J., Lacerda, P., Lim, T., Mommert, M., Ortiz, J. L., Rengel, M., Thirouin, A., Trilling, D., Barucci, A., Crovisier, J., Doressoundiram, A., Dotto, E., Gutiérrez, P. J., Hainaut, O. R., Hartogh, P., Hestroffer, D., Kidger, M., Lara, L., Swinyard, B., and Thomas, N.

226. Planetary science goals for the Spitzer Warm Era

Author

Carey Lisse, Sykes, M. V., Trilling, D., Emery, J., Fernandez, Y., Hammel, H. B., Bhattacharya, B., Ryan, E., Stansberry, J., Lombardistorrie, Lj, Silbermann, Na, Storrie-Lombardi, Lisa J., and Silbermann, Nancy

Subjects
Physics, Solar System, Nebula, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy, Astrophysics, Photometry (astronomy), Planetary science, Spitzer Space Telescope, Planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Formation and evolution of the Solar System, Astrophysics::Galaxy Astrophysics
Abstract

The overarching goal of planetary astronomy is to deduce how the present collection of objects found in our Solar System were formed from the original material present in the proto-solar nebula. As over two hundred exo-planetary systems are now known, and multitudes more are expected, the Solar System represents the closest and best system which we can study, and the only one in which we can clearly resolve individual bodies other than planets. In this White Paper we demonstrate how to use Spitzer Space Telescope InfraRed Array Camera Channels 1 and 2 (3.6 and 4.5 um) imaging photometry with large dedicated surveys to advance our knowledge of Solar System formation and evolution. There are a number of vital, key projects to be pursued using dedicated large programs that have not been pursued during the five years of Spitzer cold operations. We present a number of the largest and most important projects here; more will certainly be proposed once the warm era has begun, including important observations of newly discovered objects., Comment: 29 pages, 17 figures, to appear in "Science Opportunities for the Warm Spitzer Mission"

228. 'TNOs are Cool': A survey of the trans-Neptunian region

Author

Lellouch, E., Kiss, C., Pablo Santos-Sanz, Müller, T. G., Fornasier, S., Groussin, O., Lacerda, P., Ortiz, J. L., Thirouin, A., Delsanti, A., Duffard, R., Harris, A. W., Henry, F., Lim, T., Moreno, R., Mommert, M., Mueller, M., Protopapa, S., Stansberry, J., Trilling, D., Vilenius, E., Barucci, A., Crovisier, J., Doressoundiram, A., Dotto, E., Gutiérrez, P. J., Hainaut, O., Hartogh, P., Hestroffer, D., Horner, J., Jorda, L., Kidger, M., Lara, L., Rengel, M., Swinyard, B., and Thomas, N.

229. ExploreNEOs: The Warm Spitzer NEO survey

Author

Trilling, David E., Bhattacharya, B., Bottke, W. F., Chesley, S. R., Delbo, M., Emery, J. P., Fazio, G. G., Harris, A. W., Hora, J. L., Mainzer, A. K., Mueller, M., Penprase, B. E., Smith, H. A., Spahr, T. B., Stansberry, J. A., Thomas, C. A., and Astronomy

Abstract

The majority of Near Earth Objects (NEOs) originated in collisions between bodies in the main asteroid belt and have found their way into near Earth space via complex and little understood dynamical interactions. This transport of material from the main belt into the inner Solar System has shaped the histories of the terrestrial planets. However, despite their scientific importance, key characteristics of the NEO population --- such as the size distribution, mix of albedos and mineralogies, and contributions from so-called dead or dormant comets --- remain largely unexplored; some 99% of all presently known NEOs are essentially uncharacterized. We have an approved 500 hour Warm Spitzer program to derive albedos and diameters for some 700 NEOs. We will measure the size distribution of this population to understand fundamental physical processes that occur among the small bodies of our Solar System. We will measure the fraction of NEOs likely to be dead comets, with implications for the flux of organic material onto the Earth. We will measure the NEO albedo distribution, which indicates the compositional diversity among these small bodies. We will study properties of individual NEOs, including their surface properties and potentially their densities, and detailed properties of a subset of well-characterized objects. Our Warm Spitzer program will begin execution in August, 2009, and will return on average one target per day for the next two years. We will present the first results from our program at the DPS meeting. This work is based on observations made with the Spitzer Space Telescope, which is operated by JPL/Caltech, under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL/Caltech.

230. The Guaranteed Time Program with the Multiband Imaging Photometer for SIRTF (MIPS)

Author

Reike, G. H., Young, E. T., Ade, Peter A. R., Alonso-Herrero, A., Beichman, C., Dole, H., Egami, E., Engelbracht, C., Gautier, T. N., Gordon, K. D., de Graauw, T., Haller, E. E., Hines, D., Kelly, D., Lada, C., Latter, W., Low, F. J., Misselt, K., Morrison, J., Mould, J., Muzerolle, J., Neugebauer, G. X., Papovich, C., Richards, P. L., Rieke, M. J., Rivlis, G., Stansberry, J., Stapelfeldt, K., Su, K. Y., Werner, M. W., Reike, G. H., Young, E. T., Ade, Peter A. R., Alonso-Herrero, A., Beichman, C., Dole, H., Egami, E., Engelbracht, C., Gautier, T. N., Gordon, K. D., de Graauw, T., Haller, E. E., Hines, D., Kelly, D., Lada, C., Latter, W., Low, F. J., Misselt, K., Morrison, J., Mould, J., Muzerolle, J., Neugebauer, G. X., Papovich, C., Richards, P. L., Rieke, M. J., Rivlis, G., Stansberry, J., Stapelfeldt, K., Su, K. Y., and Werner, M. W.

Abstract

The GTO program for the MIPS team is concentrated in two areas. First, the evolution of planetary debris disks will be traced from their formation at less than one million years old, to the stable disks around old stars. To do so, we will make maps from 3 to 200 microns (in collaboration with the IRAC team) of regions where young stars are forming, to characterize thoroughly the circumstellar excess emission. We will include clusters representing a range of density and age. We will also observe a selection of isolated evolved stars in the MIPS photometric bands at 24, 70, and 160 microns. These observations will catalog the debris disk excesses as a function of stellar mass, age, binarity, and the presence of planetary companions. Second, we will explore the evolution of infrared galaxies and AGNs. This program has two components. In collaboration with both the IRAC and IRS teams, we will map at moderate depth 9 square degrees of sky, and in collaboration with IRAC will make deeper maps of about 2 square degrees. The latter regions have been selected to overlap with very deep xray surveys to aid in identification of AGNs and study of their evolution. We will extend the results of the deep maps by observations of 18 massive galaxy clusters in the redshift range 0.2 < z < 0.4. These clusters will image about 50 square arcmin of the background Universe, raising sources out of the confusion that will limit the sensitivity of the other deep surveys.

231. The Guaranteed Time Program with the Multiband Imaging Photometer for SIRTF (MIPS)

Author

Reike, G. H., Young, E. T., Ade, Peter A. R., Alonso-Herrero, A., Beichman, C., Dole, H., Egami, E., Engelbracht, C., Gautier, T. N., Gordon, K. D., de Graauw, T., Haller, E. E., Hines, D., Kelly, D., Lada, C., Latter, W., Low, F. J., Misselt, K., Morrison, J., Mould, J., Muzerolle, J., Neugebauer, G. X., Papovich, C., Richards, P. L., Rieke, M. J., Rivlis, G., Stansberry, J., Stapelfeldt, K., Su, K. Y., Werner, M. W., Reike, G. H., Young, E. T., Ade, Peter A. R., Alonso-Herrero, A., Beichman, C., Dole, H., Egami, E., Engelbracht, C., Gautier, T. N., Gordon, K. D., de Graauw, T., Haller, E. E., Hines, D., Kelly, D., Lada, C., Latter, W., Low, F. J., Misselt, K., Morrison, J., Mould, J., Muzerolle, J., Neugebauer, G. X., Papovich, C., Richards, P. L., Rieke, M. J., Rivlis, G., Stansberry, J., Stapelfeldt, K., Su, K. Y., and Werner, M. W.

Abstract

The GTO program for the MIPS team is concentrated in two areas. First, the evolution of planetary debris disks will be traced from their formation at less than one million years old, to the stable disks around old stars. To do so, we will make maps from 3 to 200 microns (in collaboration with the IRAC team) of regions where young stars are forming, to characterize thoroughly the circumstellar excess emission. We will include clusters representing a range of density and age. We will also observe a selection of isolated evolved stars in the MIPS photometric bands at 24, 70, and 160 microns. These observations will catalog the debris disk excesses as a function of stellar mass, age, binarity, and the presence of planetary companions. Second, we will explore the evolution of infrared galaxies and AGNs. This program has two components. In collaboration with both the IRAC and IRS teams, we will map at moderate depth 9 square degrees of sky, and in collaboration with IRAC will make deeper maps of about 2 square degrees. The latter regions have been selected to overlap with very deep xray surveys to aid in identification of AGNs and study of their evolution. We will extend the results of the deep maps by observations of 18 massive galaxy clusters in the redshift range 0.2 < z < 0.4. These clusters will image about 50 square arcmin of the background Universe, raising sources out of the confusion that will limit the sensitivity of the other deep surveys.

232. Two NIRCam Channels are Better than One: How JWSTCan Do More Science with NIRCam's Short-wavelength Dispersed Hartmann Sensor

Author

Schlawin, E., Rieke, M., Leisenring, J., Walker, L. M., Fraine, J., Kelly, D., Misselt, K., Greene, T., Line, M., Lewis, N., and Stansberry, J.

Abstract

The James Webb Space Telescope(JWST) offers unprecedented sensitivity, stability, and wavelength coverage for transiting exoplanet studies, opening up new avenues for measuring atmospheric abundances, structure, and temperature profiles. Taking full advantage of JWSTspectroscopy of planets from 0.6 to 28 ?m, however, will require many observations with a combination of the NIRISS, NIRCam, NIRSpec, and MIRI instruments. In this white paper, we discuss a new NIRCam mode (not yet approved or implemented) that can reduce the number of necessary observations to cover the 1.0-5.0 ?m wavelength range. Even though NIRCam was designed primarily as an imager, it also includes several grisms for phasing and aligning JWST's 18 hexagonal mirror segments. NIRCam's long-wavelength channel includes grisms that cover 2.4-5.0 ?m with a resolving power of R= 1200-1550 using two separate configurations. The long-wavelength grisms have already been approved for science operations, including wide field and single object (time series) slitless spectroscopy. We propose a new mode that will simultaneously measure spectra for science targets in the 1.0-2.0 ?m range using NIRCam's short-wavelength channel. This mode, if approved, would take advantage of NIRCam's Dispersed Hartmann Sensor (DHS), which produces 10 spatially separated spectra per source at R? 300. We discuss the added benefit of the DHS in constraining abundances in exoplanet atmospheres as well as its ability to observe the brightest systems. The DHS essentially comes for free (at no time cost) with any NIRCam long-wavelength grism observation, but the detector integration parameters have to be selected to ensure that the long-wavelength grism observations do not saturate and that JWSTdata volume downlink constraints are not violated. Combining both of NIRCam's channels will maximize the science potential of JWST, which is a limited life observatory.

Published
2017
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233. James Webb Space TelescopeObservations of Stellar Occultations by Solar System Bodies and Rings

Author

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.

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 JWSToccultation 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 JWSTnear 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 JWSTobserving 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.

Published
2016
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234. Endogenous CO2 ice mixture on the surface of Europa and no detection of plume activity.

Author

Villanueva, G. L., Hammel, H. B., Milam, S. N., Faggi, S., Kofman, V., Roth, L., Hand, K. P., Paganini, L., Stansberry, J., Spencer, J., Protopapa, S., Strazzulla, G., Cruz-Mermy, G., Glein, C. R., Cartwright, R., and Liuzzi, G.

Subjects
*EUROPA (Satellite), *CARBON dioxide, *CARBON monoxide, *SPACE telescopes
Abstract

Jupiter’s moon Europa has a subsurface ocean beneath an icy crust. Conditions within the ocean are unknown, and it is unclear whether it is connected to the surface. We observed Europa with the James Webb Space Telescope (JWST) to search for active release of material by probing its surface and atmosphere. A search for plumes yielded no detection of water, carbon monoxide, methanol, ethane, or methane fluorescence emissions. Four spectral features of carbon dioxide (CO2) ice were detected; their spectral shapes and distribution across Europa’s surface indicate that the CO2 is mixed with other compounds and concentrated in Tara Regio. The 13CO2 absorption is consistent with an isotopic ratio of 12C/13C = 83 ± 19. We interpret these observations as indicating that carbon is sourced from within Europa. [ABSTRACT FROM AUTHOR]

Published
2023
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239. Detection of CO and HCN in Pluto’s atmosphere with ALMA.

Author

Lellouch, E., Gurwell, M., Butler, B., Fouchet, T., Lavvas, P., Strobel, D.F., Sicardy, B., Moullet, A., Moreno, R., Bockelée-Morvan, D., Biver, N., Young, L., Lis, D., Stansberry, J., Stern, A., Weaver, H., Young, E., Zhu, X., and Boissier, J.

Subjects
*CHARON (Satellite), *PLUTO (Dwarf planet), *CARBON monoxide, *CONDENSATION (Meteorology), *HYDROCYANIC acid, *MESOSPHERE
Abstract

Observations of the Pluto-Charon system, acquired with the ALMA interferometer on June 12–13, 2015, have led to the detection of the CO(3-2) and HCN(4-3) rotational transitions from Pluto (including the hyperfine structure of HCN), providing a strong confirmation of the presence of CO, and the first observation of HCN in Pluto’s atmosphere. The CO and HCN lines probe Pluto’s atmosphere up to ∼450 km and ∼900 km altitude, respectively, with a large contribution due to limb emission. The CO detection yields (i) a much improved determination of the CO mole fraction, as 515 ± 40 ppm for a 12 μ bar surface pressure (ii) strong constraints on Pluto’s mean atmospheric dayside temperature profile over ∼50–400 km, with clear evidence for a well-marked temperature decrease (i.e., mesosphere) above the 30–50 km stratopause and a best-determined temperature of 70 ± 2 K at 300 km, somewhat lower than previously estimated from stellar occultations (81 ± 6 K), and in agreement with recent inferences from New Horizons / Alice solar occultation data. The HCN line shape implies a high abundance of this species in the upper atmosphere, with a mole fraction >1.5 × 10 − 5 above 450 km and a value of 4 × 10 − 5 near 800 km. Assuming HCN at saturation, this would require a warm (>92 K) upper atmosphere layer; while this is not ruled out by the CO emission, it is inconsistent with the Alice-measured CH 4 and N 2 line-of-sight column densities. Taken together, the large HCN abundance and the cold upper atmosphere imply supersaturation of HCN to a degree (7–8 orders of magnitude) hitherto unseen in planetary atmospheres, probably due to a lack of condensation nuclei above the haze region and the slow kinetics of condensation at the low pressure and temperature conditions of Pluto’s upper atmosphere. HCN is also present in the bottom ∼100 km of the atmosphere, with a 10 − 8 –10 − 7 mole fraction; this implies either HCN saturation or undersaturation there, depending on the precise stratopause temperature. The HCN column is (1.6 ± 0.4)× 10 14 cm − 2 , suggesting a surface-referred vertically-integrated net production rate of ∼2 × 10 7 cm − 2 s − 1 . Although HCN rotational line cooling affects Pluto’s atmosphere heat budget, the amounts determined in this study are insufficient to explain the well-marked mesosphere and upper atmosphere’s ∼70 K temperature, which if controlled by HCN cooling would require HCN mole fractions of (3–7) × 10 − 4 over 400–800 km. We finally report an upper limit on the HC 3 N column density (<2 × 10 13 cm − 2 ) and on the HC 15 N / HC 14 N ratio (<1/125). [ABSTRACT FROM AUTHOR]

Published
2017
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240. The Science Performance of JWST as Characterized in Commissioning

Author

Jane Rigby, Marshall Perrin, Michael McElwain, Randy Kimble, Scott Friedman, Matt Lallo, René Doyon, Lee Feinberg, Pierre Ferruit, Alistair Glasse, Marcia Rieke, George Rieke, Gillian Wright, Chris Willott, Knicole Colon, Stefanie Milam, Susan Neff, Christopher Stark, Jeff Valenti, Jim Abell, Faith Abney, Yasin Abul-Huda, D. Scott Acton, Evan Adams, David Adler, Jonathan Aguilar, Nasif Ahmed, Loïc Albert, Stacey Alberts, David Aldridge, Marsha Allen, Martin Altenburg, Javier Álvarez-Márquez, Catarina Alves de Oliveira, Greg Andersen, Harry Anderson, Sara Anderson, Ioannis Argyriou, Amber Armstrong, Santiago Arribas, Etienne Artigau, Amanda Arvai, Charles Atkinson, Gregory Bacon, Thomas Bair, Kimberly Banks, Jaclyn Barrientes, Bruce Barringer, Peter Bartosik, William Bast, Pierre Baudoz, Thomas Beatty, Katie Bechtold, Tracy Beck, Eddie Bergeron, Matthew Bergkoetter, Rachana Bhatawdekar, Stephan Birkmann, Ronald Blazek, Claire Blome, Anthony Boccaletti, Torsten Böker, John Boia, Nina Bonaventura, Nicholas Bond, Kari Bosley, Ray Boucarut, Matthew Bourque, Jeroen Bouwman, Gary Bower, Charles Bowers, Martha Boyer, Larry Bradley, Greg Brady, Hannah Braun, David Breda, Pamela Bresnahan, Stacey Bright, Christopher Britt, Asa Bromenschenkel, Brian Brooks, Keira Brooks, Bob Brown, Matthew Brown, Patricia Brown, Andy Bunker, Matthew Burger, Howard Bushouse, Steven Cale, Alex Cameron, Peter Cameron, Alicia Canipe, James Caplinger, Francis Caputo, Mihai Cara, Larkin Carey, Stefano Carniani, Maria Carrasquilla, Margaret Carruthers, Michael Case, Riggs Catherine, Don Chance, George Chapman, Stéphane Charlot, Brian Charlow, Pierre Chayer, Bin Chen, Brian Cherinka, Sarah Chichester, Zack Chilton, Taylor Chonis, Mark Clampin, Charles Clark, Kerry Clark, Dan Coe, Benee Coleman, Brian Comber, Tom Comeau, Dennis Connolly, James Cooper, Rachel Cooper, Eric Coppock, Matteo Correnti, Christophe Cossou, Alain Coulais, Laura Coyle, Misty Cracraft, Mirko Curti, Steven Cuturic, Katherine Davis, Michael Davis, Bruce Dean, Amy DeLisa, Wim deMeester, Nadia Dencheva, Nadezhda Dencheva, Joseph DePasquale, Jeremy Deschenes, Örs Hunor Detre, Rosa Diaz, Dan Dicken, Audrey DiFelice, Matthew Dillman, William Dixon, Jesse Doggett, Tom Donaldson, Rob Douglas, Kimberly DuPrie, Jean Dupuis, John Durning, Nilufar Easmin, Weston Eck, Chinwe Edeani, Eiichi Egami, Ralf Ehrenwinkler, Jonathan Eisenhamer, Michael Eisenhower, Michelle Elie, James Elliott, Kyle Elliott, Tracy Ellis, Michael Engesser, Nestor Espinoza, Odessa Etienne, Mireya Etxaluze, Patrick Falini, Matthew Feeney, Malcolm Ferry, Joseph Filippazzo, Brian Fincham, Mees Fix, Nicolas Flagey, Michael Florian, Jim Flynn, Erin Fontanella, Terrance Ford, Peter Forshay, Ori Fox, David Franz, Henry Fu, Alexander Fullerton, Sergey Galkin, Anthony Galyer, Macarena García Marín, Jonathan P. Gardner, Lisa Gardner, Dennis Garland, Bruce Garrett, Danny Gasman, Andras Gaspar, Daniel Gaudreau, Peter Gauthier, Vincent Geers, Paul Geithner, Mario Gennaro, Giovanna Giardino, Julien Girard, Mark Giuliano, Kirk Glassmire, Adrian Glauser, Stuart Glazer, John Godfrey, David Golimowski, David Gollnitz, Fan Gong, Shireen Gonzaga, Michael Gordon, Karl Gordon, Paul Goudfrooij, Thomas Greene, Matthew Greenhouse, Stefano Grimaldi, Andrew Groebner, Timothy Grundy, Pierre Guillard, Irvin Gutman, Kong Q. Ha, Peter Haderlein, Andria Hagedorn, Kevin Hainline, Craig Haley, Maryam Hami, Forrest Hamilton, Heidi Hammel, Carl Hansen, Tom Harkins, Michael Harr, Jessica Hart, Quyen Hart, George Hartig, Ryan Hashimoto, Sujee Haskins, William Hathaway, Keith Havey, Brian Hayden, Karen Hecht, Chris Heller-Boyer, Caroline Henriques, Alaina Henry, Karl Hermann, Scarlin Hernandez, Brigette Hesman, Brian Hicks, Bryan Hilbert, Dean Hines, Melissa Hoffman, Sherie Holfeltz, Bryan J. Holler, Jennifer Hoppa, Kyle Hott, Joseph M. Howard, Rick Howard, Alexander Hunter, David Hunter, Brendan Hurst, Bernd Husemann, Leah Hustak, Luminita Ilinca Ignat, Garth Illingworth, Sandra Irish, Wallace Jackson, Amir Jahromi, Peter Jakobsen, LeAndrea James, Bryan James, William Januszewski, Ann Jenkins, Hussein Jirdeh, Phillip Johnson, Timothy Johnson, Vicki Jones, Ron Jones, Danny Jones, Olivia Jones, Ian Jordan, Margaret Jordan, Sarah Jurczyk, Alden Jurling, Catherine Kaleida, Phillip Kalmanson, Jens Kammerer, Huijo Kang, Shaw-Hong Kao, Diane Karakla, Patrick Kavanagh, Doug Kelly, Sarah Kendrew, Herbert Kennedy, Deborah Kenny, Ritva Keski-kuha, Charles Keyes, Richard Kidwell, Wayne Kinzel, Jeff Kirk, Mark Kirkpatrick, Danielle Kirshenblat, Pamela Klaassen, Bryan Knapp, J. Scott Knight, Perry Knollenberg, Robert Koehler, Anton Koekemoer, Aiden Kovacs, Trey Kulp, Nimisha Kumari, Mark Kyprianou, Stephanie La Massa, Aurora Labador, Alvaro Labiano, Pierre-Olivier Lagage, Charles-Philippe Lajoie, Matthew Lallo, May Lam, Tracy Lamb, Scott Lambros, Richard Lampenfield, James Langston, Kirsten Larson, David Law, Jon Lawrence, David Lee, Jarron Leisenring, Kelly Lepo, Michael Leveille, Nancy Levenson, Marie Levine, Zena Levy, Dan Lewis, Hannah Lewis, Mattia Libralato, Paul Lightsey, Miranda Link, Lily Liu, Amy Lo, Alexandra Lockwood, Ryan Logue, Chris Long, Douglas Long, Charles Loomis, Marcos Lopez-Caniego, Jose Lorenzo Alvarez, Jennifer Love-Pruitt, Adrian Lucy, Nora Luetzgendorf, Peiman Maghami, Roberto Maiolino, Melissa Major, Sunita Malla, Eliot Malumuth, Elena Manjavacas, Crystal Mannfolk, Amanda Marrione, Anthony Marston, André Martel, Marc Maschmann, Gregory Masci, Michaela Masciarelli, Michael Maszkiewicz, John Mather, Kenny McKenzie, Brian McLean, Matthew McMaster, Katie Melbourne, Marcio Meléndez, Michael Menzel, Kaiya Merz, Michele Meyett, Luis Meza, Cherie Miskey, Karl Misselt, Christopher Moller, Jane Morrison, Ernie Morse, Harvey Moseley, Gary Mosier, Matt Mountain, Julio Mueckay, Michael Mueller, Susan Mullally, Jess Murphy, Katherine Murray, Claire Murray, David Mustelier, James Muzerolle, Matthew Mycroft, Richard Myers, Kaila Myrick, Shashvat Nanavati, Elizabeth Nance, Omnarayani Nayak, Bret Naylor, Edmund Nelan, Bryony Nickson, Alethea Nielson, Maria Nieto-Santisteban, Nikolay Nikolov, Alberto Noriega-Crespo, Brian O’Shaughnessy, Brian O’Sullivan, William Ochs, Patrick Ogle, Brenda Oleszczuk, Joseph Olmsted, Shannon Osborne, Richard Ottens, Beverly Owens, Camilla Pacifici, Alyssa Pagan, James Page, Sang Park, Keith Parrish, Polychronis Patapis, Lee Paul, Tyler Pauly, Cheryl Pavlovsky, Andrew Pedder, Matthew Peek, Maria Pena-Guerrero, Konstantin Penanen, Yesenia Perez, Michele Perna, Beth Perriello, Kevin Phillips, Martin Pietraszkiewicz, Jean-Paul Pinaud, Norbert Pirzkal, Joseph Pitman, Aidan Piwowar, Vera Platais, Danielle Player, Rachel Plesha, Joe Pollizi, Ethan Polster, Klaus Pontoppidan, Blair Porterfield, Charles Proffitt, Laurent Pueyo, Christine Pulliam, Brian Quirt, Irma Quispe Neira, Rafael Ramos Alarcon, Leah Ramsay, Greg Rapp, Robert Rapp, Bernard Rauscher, Swara Ravindranath, Timothy Rawle, Michael Regan, Timothy A. Reichard, Carl Reis, Michael E. Ressler, Armin Rest, Paul Reynolds, Timothy Rhue, Karen Richon, Emily Rickman, Michael Ridgaway, Christine Ritchie, Hans-Walter Rix, Massimo Robberto, Gregory Robinson, Michael Robinson, Orion Robinson, Frank Rock, David Rodriguez, Bruno Rodriguez Del Pino, Thomas Roellig, Scott Rohrbach, Anthony Roman, Fred Romelfanger, Perry Rose, Anthony Roteliuk, Marc Roth, Braden Rothwell, Neil Rowlands, Arpita Roy, Pierre Royer, Patricia Royle, Chunlei Rui, Peter Rumler, Joel Runnels, Melissa Russ, Zafar Rustamkulov, Grant Ryden, Holly Ryer, Modhumita Sabata, Derek Sabatke, Elena Sabbi, Bridget Samuelson, Benjamin Sapp, Bradley Sappington, B. Sargent, Arne Sauer, Silvia Scheithauer, Everett Schlawin, Joseph Schlitz, Tyler Schmitz, Analyn Schneider, Jürgen Schreiber, Vonessa Schulze, Ryan Schwab, John Scott, Kenneth Sembach, Clare Shanahan, Bryan Shaughnessy, Richard Shaw, Nanci Shawger, Christopher Shay, Evan Sheehan, Sharon Shen, Allan Sherman, Bernard Shiao, Hsin-Yi Shih, Irene Shivaei, Matthew Sienkiewicz, David Sing, Marco Sirianni, Anand Sivaramakrishnan, Joy Skipper, G. C. Sloan, Christine Slocum, Steven Slowinski, Erin Smith, Eric Smith, Denise Smith, Corbett Smith, Gregory Snyder, Warren Soh, Sangmo Tony Sohn, Christian Soto, Richard Spencer, Scott Stallcup, John Stansberry, Carl Starr, Elysia Starr, Alphonso Stewart, Massimo Stiavelli, Amber Straughn, David Strickland, Jeff Stys, Francis Summers, Fengwu Sun, Ben Sunnquist, Daryl Swade, Michael Swam, Robert Swaters, Robby Swoish, Joanna M. Taylor, Rolanda Taylor, Maurice Te Plate, Mason Tea, Kelly Teague, Randal Telfer, Tea Temim, Deepashri Thatte, Christopher Thompson, Linda Thompson, Shaun Thomson, Tuomo Tikkanen, William Tippet, Connor Todd, Sharon Toolan, Hien Tran, Edwin Trejo, Justin Truong, Chris Tsukamoto, Samuel Tustain, Harrison Tyra, Leonardo Ubeda, Kelli Underwood, Michael Uzzo, Julie Van Campen, Thomas Vandal, Bart Vandenbussche, Begoña Vila, Kevin Volk, Glenn Wahlgren, Mark Waldman, Chanda Walker, Michel Wander, Christine Warfield, Gerald Warner, Matthew Wasiak, Mitchell Watkins, Andrew Weaver, Mark Weilert, Nick Weiser, Ben Weiss, Sarah Weissman, Alan Welty, Garrett West, Lauren Wheate, Elizabeth Wheatley, Thomas Wheeler, Rick White, Kevin Whiteaker, Paul Whitehouse, Jennifer Whiteleather, William Whitman, Christina Williams, Christopher Willmer, Scott Willoughby, Andrew Wilson, Gregory Wirth, Emily Wislowski, Erin Wolf, David Wolfe, Schuyler Wolff, Bill Workman, Ray Wright, Carl Wu, Rai Wu, Kristen Wymer, Kayla Yates, Christopher Yeager, Jared Yeates, Ethan Yerger, Jinmi Yoon, Alice Young, Susan Yu, Dean Zak, Peter Zeidler, Julia Zhou, Thomas Zielinski, Cristian Zincke, Stephanie Zonak, Rigby, J., Perrin, M., Mcelwain, M., Kimble, R., Friedman, S., Lallo, M., Doyon, R., Feinberg, L., Ferruit, P., Glasse, A., Rieke, M., Rieke, G., Wright, G., Willott, C., Colon, K., Milam, S., Neff, S., Stark, C., Valenti, J., Abell, J., Abney, F., Abul-Huda, Y., Scott Acton, D., Adams, E., Adler, D., Aguilar, J., Ahmed, N., Albert, L., Alberts, S., Aldridge, D., Allen, M., Altenburg, M., Alvarez-Marquez, J., Alves de Oliveira, C., Andersen, G., Anderson, H., Anderson, S., Argyriou, I., Armstrong, A., Arribas, S., Artigau, E., Arvai, A., Atkinson, C., Bacon, G., Bair, T., Banks, K., Barrientes, J., Barringer, B., Bartosik, P., Bast, W., Baudoz, P., Beatty, T., Bechtold, K., Beck, T., Bergeron, E., Bergkoetter, M., Bhatawdekar, R., Birkmann, S., Blazek, R., Blome, C., Boccaletti, A., Boker, T., Boia, J., Bonaventura, N., Bond, N., Bosley, K., Boucarut, R., Bourque, M., Bouwman, J., Bower, G., Bowers, C., Boyer, M., Bradley, L., Brady, G., Braun, H., Breda, D., Bresnahan, P., Bright, S., Britt, C., Bromenschenkel, A., Brooks, B., Brooks, K., Brown, B., Brown, M., Brown, P., Bunker, A., Burger, M., Bushouse, H., Cale, S., Cameron, A., Cameron, P., Canipe, A., Caplinger, J., Caputo, F., Cara, M., Carey, L., Carniani, S., Carrasquilla, M., Carruthers, M., Case, M., Catherine, R., Chance, D., Chapman, G., Charlot, S., Charlow, B., Chayer, P., Chen, B., Cherinka, B., Chichester, S., Chilton, Z., Chonis, T., Clampin, M., Clark, C., Clark, K., Coe, D., Coleman, B., Comber, B., Comeau, T., Connolly, D., Cooper, J., Cooper, R., Coppock, E., Correnti, M., Cossou, C., Coulais, A., Coyle, L., Cracraft, M., Curti, M., Cuturic, S., Davis, K., Davis, M., Dean, B., Delisa, A., Demeester, W., Dencheva, N., Depasquale, J., Deschenes, J., Hunor Detre, I., Diaz, R., Dicken, D., Difelice, A., Dillman, M., Dixon, W., Doggett, J., Donaldson, T., Douglas, R., Duprie, K., Dupuis, J., Durning, J., Easmin, N., Eck, W., Edeani, C., Egami, E., Ehrenwinkler, R., Eisenhamer, J., Eisenhower, M., Elie, M., Elliott, J., Elliott, K., Ellis, T., Engesser, M., Espinoza, N., Etienne, O., Etxaluze, M., Falini, P., Feeney, M., Ferry, M., Filippazzo, J., Fincham, B., Fix, M., Flagey, N., Florian, M., Flynn, J., Fontanella, E., Ford, T., Forshay, P., Fox, O., Franz, D., Fu, H., Fullerton, A., Galkin, S., Galyer, A., Garcia Marin, M., Gardner, J. P., Gardner, L., Garland, D., Garrett, B., Gasman, D., Gaspar, A., Gaudreau, D., Gauthier, P., Geers, V., Geithner, P., Gennaro, M., Giardino, G., Girard, J., Giuliano, M., Glassmire, K., Glauser, A., Glazer, S., Godfrey, J., Golimowski, D., Gollnitz, D., Gong, F., Gonzaga, S., Gordon, M., Gordon, K., Goudfrooij, P., Greene, T., Greenhouse, M., Grimaldi, S., Groebner, A., Grundy, T., Guillard, P., Gutman, I., Ha, K. Q., Haderlein, P., Hagedorn, A., Hainline, K., Haley, C., Hami, M., Hamilton, F., Hammel, H., Hansen, C., Harkins, T., Harr, M., Hart, J., Hart, Q., Hartig, G., Hashimoto, R., Haskins, S., Hathaway, W., Havey, K., Hayden, B., Hecht, K., Heller-Boyer, C., Henriques, C., Henry, A., Hermann, K., Hernandez, S., Hesman, B., Hicks, B., Hilbert, B., Hines, D., Hoffman, M., Holfeltz, S., Holler, B. J., Hoppa, J., Hott, K., Howard, J. M., Howard, R., Hunter, A., Hunter, D., Hurst, B., Husemann, B., Hustak, L., Ilinca Ignat, L., Illingworth, G., Irish, S., Jackson, W., Jahromi, A., Jakobsen, P., James, L., James, B., Januszewski, W., Jenkins, A., Jirdeh, H., Johnson, P., Johnson, T., Jones, V., Jones, R., Jones, D., Jones, O., Jordan, I., Jordan, M., Jurczyk, S., Jurling, A., Kaleida, C., Kalmanson, P., Kammerer, J., Kang, H., Kao, S. -H., Karakla, D., Kavanagh, P., Kelly, D., Kendrew, S., Kennedy, H., Kenny, D., Keski-Kuha, R., Keyes, C., Kidwell, R., Kinzel, W., Kirk, J., Kirkpatrick, M., Kirshenblat, D., Klaassen, P., Knapp, B., Scott Knight, J., Knollenberg, P., Koehler, R., Koekemoer, A., Kovacs, A., Kulp, T., Kumari, N., Kyprianou, M., La Massa, S., Labador, A., Labiano, A., Lagage, P. -O., Lajoie, C. -P., Lam, M., Lamb, T., Lambros, S., Lampenfield, R., Langston, J., Larson, K., Law, D., Lawrence, J., Lee, D., Leisenring, J., Lepo, K., Leveille, M., Levenson, N., Levine, M., Levy, Z., Lewis, D., Lewis, H., Libralato, M., Lightsey, P., Link, M., Liu, L., Lo, A., Lockwood, A., Logue, R., Long, C., Long, D., Loomis, C., Lopez-Caniego, M., Lorenzo Alvarez, J., Love-Pruitt, J., Lucy, A., Luetzgendorf, N., Maghami, P., Maiolino, R., Major, M., Malla, S., Malumuth, E., Manjavacas, E., Mannfolk, C., Marrione, A., Marston, A., Martel, A., Maschmann, M., Masci, G., Masciarelli, M., Maszkiewicz, M., Mather, J., Mckenzie, K., Mclean, B., Mcmaster, M., Melbourne, K., Melendez, M., Menzel, M., Merz, K., Meyett, M., Meza, L., Miskey, C., Misselt, K., Moller, C., Morrison, J., Morse, E., Moseley, H., Mosier, G., Mountain, M., Mueckay, J., Mueller, M., Mullally, S., Murphy, J., Murray, K., Murray, C., Mustelier, D., Muzerolle, J., Mycroft, M., Myers, R., Myrick, K., Nanavati, S., Nance, E., Nayak, O., Naylor, B., Nelan, E., Nickson, B., Nielson, A., Nieto-Santisteban, M., Nikolov, N., Noriega-Crespo, A., O'Shaughnessy, B., O'Sullivan, B., Ochs, W., Ogle, P., Oleszczuk, B., Olmsted, J., Osborne, S., Ottens, R., Owens, B., Pacifici, C., Pagan, A., Page, J., Park, S., Parrish, K., Patapis, P., Paul, L., Pauly, T., Pavlovsky, C., Pedder, A., Peek, M., Pena-Guerrero, M., Penanen, K., Perez, Y., Perna, M., Perriello, B., Phillips, K., Pietraszkiewicz, M., Pinaud, J. -P., Pirzkal, N., Pitman, J., Piwowar, A., Platais, V., Player, D., Plesha, R., Pollizi, J., Polster, E., Pontoppidan, K., Porterfield, B., Proffitt, C., Pueyo, L., Pulliam, C., Quirt, B., Quispe Neira, I., Ramos Alarcon, R., Ramsay, L., Rapp, G., Rapp, R., Rauscher, B., Ravindranath, S., Rawle, T., Regan, M., Reichard, T. A., Reis, C., Ressler, M. E., Rest, A., Reynolds, P., Rhue, T., Richon, K., Rickman, E., Ridgaway, M., Ritchie, C., Rix, H. -W., Robberto, M., Robinson, G., Robinson, M., Robinson, O., Rock, F., Rodriguez, D., Rodriguez Del Pino, B., Roellig, T., Rohrbach, S., Roman, A., Romelfanger, F., Rose, P., Roteliuk, A., Roth, M., Rothwell, B., Rowlands, N., Roy, A., Royer, P., Royle, P., Rui, C., Rumler, P., Runnels, J., Russ, M., Rustamkulov, Z., Ryden, G., Ryer, H., Sabata, M., Sabatke, D., Sabbi, E., Samuelson, B., Sapp, B., Sappington, B., Sargent, B., Sauer, A., Scheithauer, S., Schlawin, E., Schlitz, J., Schmitz, T., Schneider, A., Schreiber, J., Schulze, V., Schwab, R., Scott, J., Sembach, K., Shanahan, C., Shaughnessy, B., Shaw, R., Shawger, N., Shay, C., Sheehan, E., Shen, S., Sherman, A., Shiao, B., Shih, H. -Y., Shivaei, I., Sienkiewicz, M., Sing, D., Sirianni, M., Sivaramakrishnan, A., Skipper, J., Sloan, G. C., Slocum, C., Slowinski, S., Smith, E., Smith, D., Smith, C., Snyder, G., Soh, W., Tony Sohn, S., Soto, C., Spencer, R., Stallcup, S., Stansberry, J., Starr, C., Starr, E., Stewart, A., Stiavelli, M., Straughn, A., Strickland, D., Stys, J., Summers, F., Sun, F., Sunnquist, B., Swade, D., Swam, M., Swaters, R., Swoish, R., Taylor, J. M., Taylor, R., Te Plate, M., Tea, M., Teague, K., Telfer, R., Temim, T., Thatte, D., Thompson, C., Thompson, L., Thomson, S., Tikkanen, T., Tippet, W., Todd, C., Toolan, S., Tran, H., Trejo, E., Truong, J., Tsukamoto, C., Tustain, S., Tyra, H., Ubeda, L., Underwood, K., Uzzo, M., Van Campen, J., Vandal, T., Vandenbussche, B., Vila, B., Volk, K., Wahlgren, G., Waldman, M., Walker, C., Wander, M., Warfield, C., Warner, G., Wasiak, M., Watkins, M., Weaver, A., Weilert, M., Weiser, N., Weiss, B., Weissman, S., Welty, A., West, G., Wheate, L., Wheatley, E., Wheeler, T., White, R., Whiteaker, K., Whitehouse, P., Whiteleather, J., Whitman, W., Williams, C., Willmer, C., Willoughby, S., Wilson, A., Wirth, G., Wislowski, E., Wolf, E., Wolfe, D., Wolff, S., Workman, B., Wright, R., Wu, C., Wu, R., Wymer, K., Yates, K., Yeager, C., Yeates, J., Yerger, E., Yoon, J., Young, A., Yu, S., Zak, D., Zeidler, P., Zhou, J., Zielinski, T., Zincke, C., Zonak, S., and bibliotheque, la.

Subjects
Science & Technology, Observatories, Infrared astronomy, Astronomical instrumentation, INFRARED SPECTROGRAPH NIRSPEC, FOS: Physical sciences, Astronomy and Astrophysics, Astronomy & Astrophysics, Settore FIS/05 - Astronomia e Astrofisica, Space and Planetary Science, Physical Sciences, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph], Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract

This paper characterizes the actual science performance of the James Webb Space Telescope (JWST), as determined from the six month commissioning period. We summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. Commissioning has made clear that JWST is fully capable of achieving the discoveries for which it was built. Moreover, almost across the board, the science performance of JWST is better than expected; in most cases, JWST will go deeper faster than expected. The telescope and instrument suite have demonstrated the sensitivity, stability, image quality, and spectral range that are necessary to transform our understanding of the cosmos through observations spanning from near-earth asteroids to the most distant galaxies., Comment: 5th version as accepted to PASP; 31 pages, 18 figures; https://iopscience.iop.org/article/10.1088/1538-3873/acb293

Published
2022
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241. 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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243. "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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245. Initial results from the New Horizons exploration of 2014 MU 69 , a small Kuiper Belt object.

Author

Stern SA, Weaver HA, Spencer JR, Olkin CB, Gladstone GR, Grundy WM, Moore JM, Cruikshank DP, Elliott HA, McKinnon WB, Parker JW, Verbiscer AJ, Young LA, Aguilar DA, Albers JM, Andert T, Andrews JP, Bagenal F, Banks ME, Bauer BA, Bauman JA, Bechtold KE, Beddingfield CB, Behrooz N, Beisser KB, Benecchi SD, Bernardoni E, Beyer RA, Bhaskaran S, Bierson CJ, Binzel RP, Birath EM, Bird MK, Boone DR, Bowman AF, Bray VJ, Britt DT, Brown LE, Buckley MR, Buie MW, Buratti BJ, Burke LM, Bushman SS, Carcich B, Chaikin AL, Chavez CL, Cheng AF, Colwell EJ, Conard SJ, Conner MP, Conrad CA, Cook JC, Cooper SB, Custodio OS, Dalle Ore CM, Deboy CC, Dharmavaram P, Dhingra RD, Dunn GF, Earle AM, Egan AF, Eisig J, El-Maarry MR, Engelbrecht C, Enke BL, Ercol CJ, Fattig ED, Ferrell CL, Finley TJ, Firer J, Fischetti J, Folkner WM, Fosbury MN, Fountain GH, Freeze JM, Gabasova L, Glaze LS, Green JL, Griffith GA, Guo Y, Hahn M, Hals DW, Hamilton DP, Hamilton SA, Hanley JJ, Harch A, Harmon KA, Hart HM, Hayes J, Hersman CB, Hill ME, Hill TA, Hofgartner JD, Holdridge ME, Horányi M, Hosadurga A, Howard AD, Howett CJA, Jaskulek SE, Jennings DE, Jensen JR, Jones MR, Kang HK, Katz DJ, Kaufmann DE, Kavelaars JJ, Keane JT, Keleher GP, Kinczyk M, Kochte MC, Kollmann P, Krimigis SM, Kruizinga GL, Kusnierkiewicz DY, Lahr MS, Lauer TR, Lawrence GB, Lee JE, Lessac-Chenen EJ, Linscott IR, Lisse CM, Lunsford AW, Mages DM, Mallder VA, Martin NP, May BH, McComas DJ, McNutt RL Jr, Mehoke DS, Mehoke TS, Nelson DS, Nguyen HD, Núñez JI, Ocampo AC, Owen WM, Oxton GK, Parker AH, Pätzold M, Pelgrift JY, Pelletier FJ, Pineau JP, Piquette MR, Porter SB, Protopapa S, Quirico E, Redfern JA, Regiec AL, Reitsema HJ, Reuter DC, Richardson DC, Riedel JE, Ritterbush MA, Robbins SJ, Rodgers DJ, Rogers GD, Rose DM, Rosendall PE, Runyon KD, Ryschkewitsch MG, Saina MM, Salinas MJ, Schenk PM, Scherrer JR, Schlei WR, Schmitt B, Schultz DJ, Schurr DC, Scipioni F, Sepan RL, Shelton RG, Showalter MR, Simon M, Singer KN, Stahlheber EW, Stanbridge DR, Stansberry JA, Steffl AJ, Strobel DF, Stothoff MM, Stryk T, Stuart JR, Summers ME, Tapley MB, Taylor A, Taylor HW, Tedford RM, Throop HB, Turner LS, Umurhan OM, Van Eck J, Velez D, Versteeg MH, Vincent MA, Webbert RW, Weidner SE, Weigle GE 2nd, Wendel JR, White OL, Whittenburg KE, Williams BG, Williams KE, Williams SP, Winters HL, Zangari AM, and Zurbuchen TH

Abstract

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU 69 , a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU 69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU 69 's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Published
2019
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246. Surface compositions across Pluto and Charon.

Author

Grundy WM, Binzel RP, Buratti BJ, Cook JC, Cruikshank DP, Dalle Ore CM, Earle AM, Ennico K, Howett CJ, Lunsford AW, Olkin CB, Parker AH, Philippe S, Protopapa S, Quirico E, Reuter DC, Schmitt B, Singer KN, Verbiscer AJ, Beyer RA, Buie MW, Cheng AF, Jennings DE, Linscott IR, Parker JW, Schenk PM, Spencer JR, Stansberry JA, Stern SA, Throop HB, Tsang CC, Weaver HA, Weigle GE 2nd, and Young LA

Abstract

The New Horizons spacecraft mapped colors and infrared spectra across the encounter hemispheres of Pluto and Charon. The volatile methane, carbon monoxide, and nitrogen ices that dominate Pluto's surface have complicated spatial distributions resulting from sublimation, condensation, and glacial flow acting over seasonal and geological time scales. Pluto's water ice "bedrock" was also mapped, with isolated outcrops occurring in a variety of settings. Pluto's surface exhibits complex regional color diversity associated with its distinct provinces. Charon's color pattern is simpler, dominated by neutral low latitudes and a reddish northern polar region. Charon's near-infrared spectra reveal highly localized areas with strong ammonia absorption tied to small craters with relatively fresh-appearing impact ejecta., (Copyright © 2016, American Association for the Advancement of Science.)

Published
2016
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