1
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Wisdom J, Dbouk R, Militzer B, Hubbard WB, Nimmo F, Downey BG, French RG. Loss of a satellite could explain Saturn’s obliquity and young rings. Science 2022; 377:1285-1289. [DOI: 10.1126/science.abn1234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The origin of Saturn’s ~26.7° obliquity and ~100-million-year-old rings is unknown. The observed rapid outward migration of Saturn’s largest satellite, Titan, could have raised Saturn’s obliquity through a spin-orbit precession resonance with Neptune. We use Cassini data to refine estimates of Saturn’s moment of inertia, finding that it is just outside the range required for the resonance. We propose that Saturn previously had an additional satellite, which we name Chrysalis, that caused Saturn’s obliquity to increase through the Neptune resonance. Destabilization of Chrysalis’s orbit ~100 million years ago can then explain the proximity of the system to the resonance and the formation of the rings through a grazing encounter with Saturn.
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Affiliation(s)
- Jack Wisdom
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Rola Dbouk
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Burkhard Militzer
- Department of Astronomy, University of California, Berkeley, CA 94720, USA
- Department of Earth and Planetary Science, University of California, Berkeley, CA 94720, USA
| | - William B. Hubbard
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721-0092, USA
| | - Francis Nimmo
- Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064, USA
| | - Brynna G. Downey
- Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064, USA
| | - Richard G. French
- Department of Astronomy, Wellesley College, Wellesley, MA 02481, USA
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2
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Kaspi Y, Galanti E, Hubbard WB, Stevenson DJ, Bolton SJ, Iess L, Guillot T, Bloxham J, Connerney JEP, Cao H, Durante D, Folkner WM, Helled R, Ingersoll AP, Levin SM, Lunine JI, Miguel Y, Militzer B, Parisi M, Wahl SM. Jupiter's atmospheric jet streams extend thousands of kilometres deep. Nature 2018. [PMID: 29516995 DOI: 10.1038/nature25793] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The depth to which Jupiter's observed east-west jet streams extend has been a long-standing question. Resolving this puzzle has been a primary goal for the Juno spacecraft, which has been in orbit around the gas giant since July 2016. Juno's gravitational measurements have revealed that Jupiter's gravitational field is north-south asymmetric, which is a signature of the planet's atmospheric and interior flows. Here we report that the measured odd gravitational harmonics J3, J5, J7 and J9 indicate that the observed jet streams, as they appear at the cloud level, extend down to depths of thousands of kilometres beneath the cloud level, probably to the region of magnetic dissipation at a depth of about 3,000 kilometres. By inverting the measured gravity values into a wind field, we calculate the most likely vertical profile of the deep atmospheric and interior flow, and the latitudinal dependence of its depth. Furthermore, the even gravity harmonics J8 and J10 resulting from this flow profile also match the measurements, when taking into account the contribution of the interior structure. These results indicate that the mass of the dynamical atmosphere is about one per cent of Jupiter's total mass.
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Affiliation(s)
- Y Kaspi
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - E Galanti
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - W B Hubbard
- Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721, USA
| | - D J Stevenson
- Divison of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA
| | - S J Bolton
- Southwest Research Institute, San Antonio, Texas 78238, USA
| | - L Iess
- Department of Mechanical and Aerospace Engineering, Sapienza Universita di Roma, 00184 Rome, Italy
| | - T Guillot
- Université Côte d'Azur, OCA, Lagrange CNRS, 06304 Nice, France
| | - J Bloxham
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - J E P Connerney
- Space Research Corporation, Annapolis, Maryland 21403, USA.,NASA/GSFC, Greenbelt, Maryland 20771, USA
| | - H Cao
- Divison of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA.,Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - D Durante
- Department of Mechanical and Aerospace Engineering, Sapienza Universita di Roma, 00184 Rome, Italy
| | - W M Folkner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - R Helled
- Institute for Computational Science, Center for Theoretical Astrophysics and Cosmology, University of Zurich, 8057 Zurich, Switzerland
| | - A P Ingersoll
- Divison of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, USA
| | - S M Levin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - J I Lunine
- Department of Astronomy, Cornell University, Ithaca, New York 14853, USA
| | - Y Miguel
- Université Côte d'Azur, OCA, Lagrange CNRS, 06304 Nice, France.,Leiden Observatory, University of Leiden, Leiden, The Netherlands
| | - B Militzer
- Department of Earth and Planetray Science, University of California, Berkeley, California 94720, USA
| | - M Parisi
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA
| | - S M Wahl
- Department of Earth and Planetray Science, University of California, Berkeley, California 94720, USA
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3
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Bolton SJ, Adriani A, Adumitroaie V, Allison M, Anderson J, Atreya S, Bloxham J, Brown S, Connerney JEP, DeJong E, Folkner W, Gautier D, Grassi D, Gulkis S, Guillot T, Hansen C, Hubbard WB, Iess L, Ingersoll A, Janssen M, Jorgensen J, Kaspi Y, Levin SM, Li C, Lunine J, Miguel Y, Mura A, Orton G, Owen T, Ravine M, Smith E, Steffes P, Stone E, Stevenson D, Thorne R, Waite J, Durante D, Ebert RW, Greathouse TK, Hue V, Parisi M, Szalay JR, Wilson R. Jupiter's interior and deep atmosphere: The initial pole-to-pole passes with the Juno spacecraft. Science 2018; 356:821-825. [PMID: 28546206 DOI: 10.1126/science.aal2108] [Citation(s) in RCA: 186] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 05/01/2017] [Indexed: 11/02/2022]
Abstract
On 27 August 2016, the Juno spacecraft acquired science observations of Jupiter, passing less than 5000 kilometers above the equatorial cloud tops. Images of Jupiter's poles show a chaotic scene, unlike Saturn's poles. Microwave sounding reveals weather features at pressures deeper than 100 bars, dominated by an ammonia-rich, narrow low-latitude plume resembling a deeper, wider version of Earth's Hadley cell. Near-infrared mapping reveals the relative humidity within prominent downwelling regions. Juno's measured gravity field differs substantially from the last available estimate and is one order of magnitude more precise. This has implications for the distribution of heavy elements in the interior, including the existence and mass of Jupiter's core. The observed magnetic field exhibits smaller spatial variations than expected, indicative of a rich harmonic content.
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Affiliation(s)
- S J Bolton
- Southwest Research Institute, San Antonio, TX 78238, USA.
| | - A Adriani
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, 00133 Rome, Italy
| | - V Adumitroaie
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - M Allison
- Goddard Institute for Space Studies, New York, NY 10025, USA
| | - J Anderson
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - S Atreya
- University of Michigan, Ann Arbor, MI 48109, USA
| | - J Bloxham
- Harvard University, Cambridge, MA 02138, USA
| | - S Brown
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - J E P Connerney
- Space Research Corporation, Annapolis, MD 21403, USA.,NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - E DeJong
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - W Folkner
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - D Gautier
- Laboratoire d'Études Spatiales et d'Instrumentation en Astrophysique, Observatoire de Paris, 92195 Meudon, France
| | - D Grassi
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, 00133 Rome, Italy
| | - S Gulkis
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - T Guillot
- Université Côte d'Azur, Observatoire de la Côte d'Azur, Laboratoire Lagrange CNRS, 06304 Nice, France
| | - C Hansen
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - W B Hubbard
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
| | - L Iess
- Sapienza University of Rome, 00185 Rome, Italy
| | - A Ingersoll
- California Institute of Technology, Pasadena, CA 91125, USA
| | - M Janssen
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - J Jorgensen
- National Space Institute, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Y Kaspi
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - S M Levin
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - C Li
- California Institute of Technology, Pasadena, CA 91125, USA
| | - J Lunine
- Cornell University, Ithaca, NY 14853, USA
| | - Y Miguel
- Université Côte d'Azur, Observatoire de la Côte d'Azur, Laboratoire Lagrange CNRS, 06304 Nice, France
| | - A Mura
- Institute for Space Astrophysics and Planetology, National Institute for Astrophysics, 00133 Rome, Italy
| | - G Orton
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - T Owen
- Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - M Ravine
- Malin Space Science Systems, San Diego, CA 92121, USA
| | - E Smith
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - P Steffes
- Center for Space Technology and Research, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - E Stone
- California Institute of Technology, Pasadena, CA 91125, USA
| | - D Stevenson
- California Institute of Technology, Pasadena, CA 91125, USA
| | - R Thorne
- Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA 90095, USA
| | - J Waite
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - D Durante
- Sapienza University of Rome, 00185 Rome, Italy
| | - R W Ebert
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - T K Greathouse
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - V Hue
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - M Parisi
- Jet Propulsion Laboratory/Caltech, Pasadena, CA 91109, USA
| | - J R Szalay
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - R Wilson
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
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Abstract
In response to the lack of therapeutics for internal bleeding following a traumatic event, we synthesized hemostatic dexamethasone nanoparticles (hDNP) to help alleviate internal hemorrhaging. hDNP consist of a block copolymer, poly(lactic-co-glycolic acid)-poly(l-lysine)-poly(ethylene glycol) conjugated to a peptide, glycine-arginine-glycine-aspartic acid-serine (GRGDS). These particles were evaluated as treatment for primary blast lung injury in a rodent model. Animals were randomly placed into test and control groups, exposed to blast and given immediate injection. Recovery was assessed using physiological parameters and immunohistochemistry. We found that dexamethasone-loaded hemostatic nanoparticles alleviate physiological deprivation caused by blast injury and reduce lung injury damage.
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Affiliation(s)
- William B. Hubbard
- School of Biomedical Engineering and Sciences, Virginia Tech University, Blacksburg, VA
| | | | - Erin B. Lavik
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH
| | - Pamela J. VandeVord
- School of Biomedical Engineering and Sciences, Virginia Tech University, Blacksburg, VA
- Research Services, Salem VAMC, Salem, VA
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5
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Kaspi Y, Showman AP, Hubbard WB, Aharonson O, Helled R. Atmospheric confinement of jet streams on Uranus and Neptune. Nature 2013; 497:344-7. [DOI: 10.1038/nature12131] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 03/22/2013] [Indexed: 11/09/2022]
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6
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Hockey KS, Hubbard WB, Sajja VS, Sholar CA, Thorpe C, Vandevord PJ, Rzigalinski BA. A new model for mild blast injury utilizing Drosophila melanogaster - biomed 2013. Biomed Sci Instrum 2013; 49:134-140. [PMID: 23686192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Current models for blast injury involve the use of mammalian species, which are costly and require extensive monitoring and housing, making it difficult to generate large numbers of injuries. The fruit fly, Drosophila melanogaster, has been utilized for many models of human disease including neurodegenerative disorders such as Parkinsons and Alzheimers diseases. In this study, a model of blast injury was designed based on Drosophila, to provide a mechanism to investigate blast injury in large numbers and assess biochemical mechanisms of brain injury. Such studies may be used to identify specific pathways involved in blast-associated neurodegeneration, allowing more effective use of mammalian models. A custom-built blast wave simulator (ORA Inc.), comprised of a driver, test section, and wave eliminator, was used to create a blast wave. An acetate membrane was placed between the driver and the rectangular test section before compressed helium caused the membrane to rupture creating the blast wave. Membrane thickness correlates with the blast wave magnitude, which averaged 120 kPa for this experiment. Pressure sensors were inserted into the side of the tube in order to quantify the level of overpressure that the flies were exposed to. Five day old flies were held in a rectangular enclosed mesh fixture (10 flies per enclosure) which was placed in the center of the test section for blast delivery. Sham controls were exposed to same conditions with exception of blast. Lifespan and negative geotaxis, a measurement of motor function, was measured in flies after blast injury. Mild blast resulted in death of 28% of the flies. In surviving flies, motor function was initially reduced, but flies regained normal function by 8 days after injury. Although surviving flies regained normal motor function, flies subjected to mild blast died earlier than uninjured controls, with a 15.4% reduction in maximum lifespan and a 17% reduction in average lifespan, mimicking the scenario observed in humans exposed to mild blast. Although further work is needed, results suggest that utilizing Drosophila as a blast model may provide a rapid, effective means of assessing physiological and biochemical changes induced by mild blast.
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7
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Abstract
Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-calied planetary ;;ice,'' have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.
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Abstract
An object in the vicinity of Neptune detected in 1981 by simultaneous stellar occultation measurements at observatories near Tucson, Arizona, was interpreted as a new Neptune satellite. A reinterpretation suggests that it may have instead been a Neptune arc similar to one observed in 1984. The 1981 object, however, did not occult the star during simultaneous observations at Flagstaff, Arizona. This result constrains possible arc geometries.
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10
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Burrows A, Guillot T, Hubbard WB, Marley MS, Saumon D, Lunine JI, Sudarsky D. On the Radii of Close-in Giant Planets. Astrophys J 2000; 534:L97-L100. [PMID: 10790080 DOI: 10.1086/312638] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2000] [Accepted: 03/09/2000] [Indexed: 05/23/2023]
Abstract
The recent discovery that the close-in extrasolar giant planet HD 209458b transits its star has provided a first-of-its-kind measurement of the planet's radius and mass. In addition, there is a provocative detection of the light reflected off of the giant planet tau Bootis b. Including the effects of stellar irradiation, we estimate the general behavior of radius/age trajectories for such planets and interpret the large measured radii of HD 209458b and tau Boo b in that context. We find that HD 209458b must be a hydrogen-rich gas giant. Furthermore, the large radius of a close-in gas giant is not due to the thermal expansion of its atmosphere but to the high residual entropy that remains throughout its bulk by dint of its early proximity to a luminous primary. The large stellar flux does not inflate the planet but retards its otherwise inexorable contraction from a more extended configuration at birth. This implies either that such a planet was formed near its current orbital distance or that it migrated in from larger distances (>/=0.5 AU), no later than a few times 107 yr of birth.
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Affiliation(s)
- W B Hubbard
- Lunar and Planetary Laboratory, University of Tuscon, AZ 85721, USA.
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12
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Abstract
Molecules such as C
2
H
2
and C
2
H
6
have been observed in the atmosphere of Neptune, one of the giant planets composed mostly of hydrogen and helium. Planetary scientists have puzzled over whether these hydrocarbons are formed as ultraviolet light from the sun induces photochemical reactions in atmospheric methane. In his Perspective, Hubbard discusses simulations reported in the same issue by Ancilotto
et al
. (p.
1288
) suggesting that C
2
H
6
may be produced by high-pressure chemical reactions deep within the planet.
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Affiliation(s)
- W B Hubbard
- University of Arizona, Tucson, AZ 87521-0092, USA
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13
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Marley MS, Saumon D, Guillot T, Freedman RS, Hubbard WB, Burrows A, Lunine JI. Atmospheric, evolutionary, and spectral models of the brown dwarf Gliese 229 B. Science 1996; 272:1919-21. [PMID: 8658164 DOI: 10.1126/science.272.5270.1919] [Citation(s) in RCA: 245] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Theoretical spectra and evolutionary models that span the giant planet-brown dwarf continuum have been computed based on the recent discovery of the brown dwarf Gliese 229 B. A flux enhancement in the 4- to 5-micrometer wavelength window is a universal feature from jovian planets to brown dwarfs. Model results confirm the existence of methane and water in the spectrum of Gliese 229 B and indicate that its mass is 30 to 55 jovian masses. Although these calculations focus on Gliese 229 B, they are also meant to guide future searches for extrasolar giant planets and brown dwarfs.
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Affiliation(s)
- M S Marley
- Department of Astronomy, New Mexico State University, Las Cruces 88003, USA.
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Iglesias CA, DeWitt HE, Lebowitz JL, MacGowan D, Hubbard WB. Low-frequency electric microfield distributions in plasmas. Phys Rev A Gen Phys 1985; 31:1698-1702. [PMID: 9895675 DOI: 10.1103/physreva.31.1698] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
The 24 May 1981 close approach of Neptune to an uncataloged star was photoelectrically monitored from two observatories separated by 6 kilometers parallel to the occultation track. An 8.1-second drop in signal, recorded simultaneously at both sites, is interpreted as resulting from the passage of a third satellite of Neptune in front of the star. From the duration of the event, the derived minimum diameter for an object sharing Neptune's motion is 180 kilometers. If the object was in Neptune's equatorial plane and there are no significant errors in the prediction ephemeris, the object was located at a distance of 3 Neptune radii from Neptune's center.
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Abstract
Unlike the terrestrial planets, the giant planets-Jupiter, Satum, Uranus, and Neptune-have retained large amounts of the carbon, nitrogen, and oxygen compounds that were present in their zone of formation. A smaller fraction of the available hydrogen and helium was retained. The distribution and relative amounts of these components in the interiors of the Jovian planets can be inferred from theoretical and expermental data on equations of state and from the planets' hydrostatic equilibrium response to rotation.
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17
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Hubbard WB, Reitsema HJ. Scintillation at two optical frequencies. Appl Opt 1981; 20:3227-3232. [PMID: 20333125 DOI: 10.1364/ao.20.003227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Stellar scintillation data were obtained on a single night at a variety of zenith distances and azimuths, using a photon-counting photometer recording at 100 Hz simultaneously at wavelengths of 0.475 microm and 0.870 microm. Orientable apertures of 42-cm diam separated by 1 m were used to establish the average upper atmosphere wind direction and velocity. Dispersion in the earth's atmosphere separate the average optical paths at the two wavelengths, permitting a reconstruction of the spatial cross-correlation function for scintillations, independent of assumptions about differential fluid motions. Although there is clear evidence of a complicated velocity field, scintillation power was predominantly produced by levels at pressures of 130 +/- 30 mbar. The data are not grossly inconsistent with layers of isotropic Kolmogorov turbulence, but there is some evidence for deviation from the Kolmogorov spectral index and/or anisotropy.
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Abstract
During the Pioneer Saturn encounter, a continuous round-trip radio link at S band ( approximately 2.2 gigahertz) was maintained between stations of the Deep Space Network and the spacecraft. From an analysis of the Doppler shift in the radio carrier frequency, it was possible to determine a number of gravitational effects on the trajectory. Gravitational moments ( J(2) and J(4)) for Saturn have been determined from preliminary analysis, and preliminary mass values have been determined for the Saturn satellites Rhea, Iapetus, and Titan. For all three satellites the densities are low, consistent with the compositions of ices. The rings have not been detected in the Doppler data, and hence the best preliminary estimate of their total mass is zero with a standard error of 3 x 10(-6) Saturn mass. New theoretical calculations for the Saturn interior are described which use the latest observational data, including Pioneer Saturn, and state-of-the-art physics for the internal composition. Probably liquid H(2)O and possibly NH(3) and CH(4) are primarily confined in Saturn to the vicinity of a core of approximately 15 to 20 Earth masses. There is a slight indication that helium may likewise be fractionated to the central regions.
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19
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Cosgrove KW, Hubbard WB. ACID AND ALKALI BURNS OF THE EYE: AN EXPERIMENTAL STUDY. Ann Surg 1928; 87:89-94. [PMID: 17865823 PMCID: PMC1398381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
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