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Four small moons--Styx, Nix, Kerberos and Hydra-follow near-circular, near-equatorial orbits around the central 'binary planet' comprising Pluto and its large moon, Charon. New observational details of the system have emerged following the discoveries of Kerberos and Styx. Here we report that Styx, Nix and Hydra are tied together by a three-body resonance, which is reminiscent of the Laplace resonance linking Jupiter's moons Io, Europa and Ganymede. Perturbations by the other bodies, however, inject chaos into this otherwise stable configuration. Nix and Hydra have bright surfaces similar to that of Charon. Kerberos may be much darker, raising questions about how a heterogeneous satellite system might have formed. Nix and Hydra rotate chaotically, driven by the large torques of the Pluto-Charon binary., Pluto's moon Kerberos (previously designated S/2011 (134340)1 or, colloquially, P4) was discovered in 2011 (1) using images from the Hubble Space Telescope (HST). It orbits between the paths of Nix [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2009.04.025 Byline: T.A. Hurford (a), B.G. Bills (b)(c), P. Helfenstein (d), R. Greenberg (e), G.V. Hoppa (f), D.P. Hamilton (g) Keywords: Tectonics; Enceladus Abstract: Given the non-spherical shape of Enceladus [], the satellite will experience gravitational torques that will cause it to physically librate as it orbits Saturn. Physical libration would produce a diurnal oscillation in the longitude of Enceladus' tidal bulge, which could have a profound effect on the diurnal tidal stresses experienced by the surface of the satellite. Although Cassini ISS has placed an observational upper limit on the amplitude of Enceladus' libration, smaller amplitudes can still have geologically significant consequences. Here we present the first detailed description of how physical libration affects tidal stresses and how those stresses might then affect geological processes including crack formation and propagation, south polar eruption activity, and tidal heating. Our goal is to provide a framework for testing the hypothesis that geologic features on Enceladus are produced by tidal stresses from diurnal librations of the satellite. Author Affiliation: (a) Planetary Systems Laboratory, NASA Goddard Spaceflight Center, Greenbelt, MD 20771, USA (b) Jet Propulsion Laboratory, Pasadena, CA 90119, USA (c) Institute for Geophysics and Planetary Physics, Scripps Institution of Oceanography, La Jolla, CA 92093, USA (d) CRSR, Cornell University, Ithaca, NY 14853, USA (e) Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA (f) Raytheon, Woburn, MA 01801, USA (g) Department of Astronomy, University of Maryland, College Park, MD 20742, USA Article History: Received 20 October 2008; Revised 16 March 2009; Accepted 17 April 2009

Identical in situ dust detectors are flown on board the Galileo and Ulysses spacecraft. They record impacts of micrometeoroids in the ecliptic plane at heliocentric distances from 0.7 to 5.4 AU and in a plane almost perpendicular to the ecliptic from -79 [degrees] to +79 [degrees] ecliptic latitude. The combination of both Ulysses and Galileo measurements yields information about the radial and latitudinal distributions of micron- and submicron-sized dust in the Solar System. Two types of dust particles were found to dominate the dust flux in interplanetary space. Interplanetary micrometeoroids covering a wide mass range from [10.sup.-16] to [10.sup.-6] g are recorded mostly inside 3 AU and at latitudes below 30 [degrees]. Interstellar grains with masses between [10.sup.-14] and [10.sup.-12] g have been positively identified outside 3 AU near the ecliptic plane and outside 1.8 AU at high ecliptic latitudes (>50 [degrees]). Interstellar grains move on hyperbolic trajectories through the planetary system and constitute the dominant dust flux (1.5 x [10.sup.-4] [m.sup.-2] [sec.sup.-1]) in the outer Solar System and at high ecliptic latitudes. To compare and analyze the Galileo and Ulysses data sets, a new model is developed based on J. Geophys. Res. 98, 17029-17048, Divine's (1993, 'five populations of interplanetary meteoroids' model. Both models describe the interplanetary meteoroid environment in terms of dust populations on distinct orbits. Taking into account the measured velocities and the effect of radiation pressure on small particles (described by the ratio of radiation pressure force to gravity, [Beta]), we define four populations of meteoroids on elliptical orbits and one population on hyperbolic orbit that can fit the micrometeoroid flux observed by Galileo and Ulysses. Micrometeoroids with masses greater than [10.sup.-10] g and negligible radiation pressure ([Beta] = 0) orbit the Sun on low to moderately eccentric orbits and with low inclinations ([less than or equal to] 30 [degrees]). Populations of smaller particles with mean masses of [10.sup.-11] g ([Beta] = 0.3), [10.sup.-13] g ([Beta] = 0.8), and 5 x [10.sup.-15] g ([Beta] = 0.3), respectively, have components with high eccentricities and have increasingly wider inclination distributions with decreasing mass. Similarities among the orbit distributions of the small particle populations on bound orbits suggest that all are genetically related and are part of an overall micrometeoroid complex that prevails in the inner Solar System. The high-eccentricity component of the small particle populations may actually be [Beta]-meteoroids which are not well characterized by our measurements. Our modeling suggests further that the interstellar dust flux is not reduced at Ulysses' perihelion distance (1.3 AU) and that it contributes about 30% of the total dust flux observed there.

The dust in the dust streams detected by the Galileo spacecraft near Jupiter originate from either the jovian gossamer ring or volcanoes on Io. The dust does not originate from the Shoemaker-Levy 9 comet as the comet has no stream activity. The dust storms detected by the Galileo dust detector are more intense and longer than those observed by the Ulysses spacecraft. The dust stream activity changes with time and there are significant differences between the intensity of the strongest and the weakest streams.

Along Ulysses' path from Jupiter to the south ecliptic pole, the onboard dust detector measured a dust impact rate that varied slowly from 0.2 to 0.5 impacts per day. The dominant component of the dust flux arrived from an ecliptic latitude and longitude of 10' ± 1O° and 280° [+ or - 30] ° which indicates an interstellar origin. An additional flux of small particles, which do not come from the interstellar direction and are unlikely to be zodiacal dust grains, appeared south of -45° latitude. One explanation is that these particles are beta-meteoroids accelerated away from the sun by radiation pressure and electromagnetic forces., The objective of the Ulysses dust detector is to measure impact directions, velocities, and masses of dust in the solar system. Here we report on results from the orbital arc [...]

From September 1991 to October 1992, the cosmic dust detector on the Ulysses spacecraft recorded 11 short bursts, or streams, of dust. These dust grains emanated from the jovian system, and their trajectories were strongly affected by solar wind magnetic field forces. Analyses of the on-board measurements of these fields, and of stream approach directions, show that stream-associated dust grain masses are of the order of [10.sup.-18] gram and dust grain velocities exceed 200 kilometers per second. These masses and velocities are, respectively, about [10.sup.3] times less massive and 5 to 10 times faster than earlier reported., While the Ulysses spacecraft was in the neighborhood of Jupiter, the on-board cosmic dust detector (CDD) detected 11 intense, and unexpected, streams of dust (1-3). The first stream occurred 2359 [...]

About a hundred dust impacts per day were detected during the first week in December 1995 by Galileo during its approach to Jupiter. These impacts were caused by submicrometer-sized particles that were just above the detection limit. After the closest approach to lo on 7, December, impacts of these small particles ceased. This effect is expected for dust grains emitted from lo that exit the field of view of the instrument after the flyby. The impact rate of bigger micrometer-sized dust grains continued to increase toward Jupiter. These dust particles are in orbit about Jupiter or are interplanetary grains that are gravitationally concentrated near Jupiter., The Galileo dust detector system (DDS) (1) like its twin aboard Ulysses (2), is an impact ionization detector that measures the plasma cloud released upon impact of submicrometer- and micrometer-sized [...]

Decades of nutrient pollution have caused water quality to decline in the nationally iconic Te Arawa (Rotorua) lakes in New Zealand. Pastoral agriculture is a major nutrient source, and therefore this degradation represents an external environmental cost to intensive farming. This cost is borne by the wider community, and a major publically funded remediation programme is now under way. This article describes the range of actions being taken to reduce nutrient loads from internal (lake bed sediments) and external (primarily diffuse) sources in the lake catchments. The high economic cost and uncertain efficacy of engineering-based actions to reduce internal nutrient loads is highlighted. Major changes to land management practices to control diffuse nutrient pollution are required throughout New Zealand if the need for costly and lengthy remediation programmes elsewhere is to be avoided. More action to educate farmers and the public about eutrophication issues, development and enforcement of environmental standards, and further consideration of the use of market-based instruments are proposed as ways to correct the current market failure. [ABSTRACT FROM PUBLISHER]

In January 2000, there was a record maximum rainfall throughout much of the watershed of the Swan River estuary. Within three weeks of this rainfall event, a large, mono-specific bloom of the cyanobacterium Microcystis aeruginosa had developed in the estuary, with cell counts peaking at over 100,000 cells ml−1. A three-dimensional, coupled hydrodynamic–ecological model, ELCOM-CAEDYM, was applied to the period of development and subsequent decline of the bloom. The model, previously calibrated for more typical years (1995 and 1996) when there was no bloom, accurately reproduced the unusual hydrodynamic conditions in the estuary as well as the approximate magnitude and timing of the M. aeruginosa bloom. The model results supported the hypothesis that salinity and temperature are the primary factors controlling the growth of M. aeruginosa during the period of interest. The simulations described in this study show how the model captures the complex interactions between the physical and biogeochemical environment, and indicate the usefulness of the model as a predictive management tool. [Copyright &y& Elsevier]

Examines changes proposed by the Public Health Service (PHS), the parent agency of the National Institutes of Health (NIH), in NIH's Office of Scientific Integrity (OSI). Criticisms of past OSI work; Criticisms of new PHS proposal; Details of reorganization plan; Plans to add a round of hearings to scientific misconduct investigation process; Concerns about unexpected consequences of hearings; More. INSET: What's left on the table.;NSF's no-fuss investigations, by D.P....

Examines the future of the Stanford Linear Accelerator Center (SLAC) particle physics lab, now that an advisory panel has recommended construction delays in a new facility as well as budget cuts. Concerns about SLAC's future in physics community;Competition from other labs in `B factory' work; Role of Stanford Linear Collider (SLC) in SLAC's current problems; SLAC's plans for its own B factory; Impact of budget cuts; Other SLAC projects. INSET: SLAC's greatest hits, by D.P.H..

Examines the efforts of Western organizations and companies to rescue scientists of the former Soviet Union, many of whom have either fled their homeland or been forced to give up their research. Benefits for Western groups; Opportunities in the former Soviet labs for companies such as University Science Partners of Ann Arbor, Michigan; Investments by the Superconducting Super Collider Laboratory (SSCL). INSET: A clearinghouse that could get clogged, by D.P.H..

Discusses the impact of results from audits of 18 major research universities made to find indirect costs abuses. Audits done by General Accounting Office (GAO) and inspector general of the Department of Health and Human Services (HHS); Evidence of persistent low-level abuse of indirect cost system by nearly all universities audited. Interpretation of results; Interim rules; Concerns; Tuition reimbursement issue. INSET: A tour through the indirect cost labyrinth, by D.P.H..

Explores conflicts surrounding the National Institutes of Health's (NIH) Office of Scientific Integrity (OSI). Criticisms from director Bernadine Healy and prominent scientists; Questions science's investigations of its own conduct; Investigationstrategies; Loss of rights by scientists being investigated; Critics of OSI's scientific dialogue model; Healy's criticisms of OSI; OSI's reactions; Future of science investigations without OSI. INSET: Jules Hallam.;Suzanne Hadley..

Discusses the decision by Superconducting Super Collider Laboratory (SSCL) director Roy Schwitters to reject a controversial detector proposed by Nobel laureate Samuel C.C. Ting. Ting's proposal to build a $760-million particle detector known as L*; Explanations by each side. INSETS: The second detector: Starting from scratch?, By D.P.H.; SSC savaged by soundbites, By D.P.H.

Reports on Nobel laureate David Baltimore's apology for his failure to `heed warnings' about fraudulent data produced by Tufts immunologist Thereza Imanishi-Kari. He also apologized to Margot O'Toole, after five years of defending the 1986 `Cell'' paper the data appeared in. Official reply to National Institutes of Health's Office of Scientific Integrity; O'Toole's comments; Comments from Baltimore's critics and supporters. INSET: David Baltimore's mea culpa..

Presents the findings of a National Institutes of Health (NIH) draft report which says that immunologist Theresa Imanishi-Kari committed `serious scientific misconduct' in her data used to back up claims made in a 1986 `Cell' paper. Rockefeller University President David Baltimore, was criticized for statements he made during the investigation. Secret service forensic analyses. INSET: Warm praise for a whistle-blower.;The report's principal....

Presents President George Bush's proposals for the research and development budget for fiscal year 1992. Biomedical research; Department of Energy; Defense R&D; Space program; National Science Foundation. INSET: Science increases will test new regime, by C.N..

Presents details of a critique of the National Institutes of Health's (NIH) Office of Scientific Integrity (OSI) investigation of Robert Gallo. The critique was made by an eight-member group known as the `Richards panel.' Panel's criticisms of OSI report; Claims that OSI tended to `trivialize' some aspects of misconduct; Criticisms of OSI for ignoring issue of lab chief's responsibilities. INSET: Where Richards and OSI part company..

Reports on the findings in a National Academy of Sciences (NAS) panel's report on scientific integrity, which recommends that universities, not the federal government, are responsible for detecting and punishing misconduct. Divisions among scientists over how to respond to misconduct; Complaints that importance and definition of misconduct are overstated in report; Difficulties in putting together the report. INSET: The academy panel's recommendations..

Describes efforts by the National Academy of Sciences to help reverse the erosion of the former Soviet Union's science and technology infrastructure collapse; Suggested course of action for United States government; Need to turn military labs intocivilian research labs; Suggested funding for aid; Opportunities for West in civilian science in the Commonwealth of Independent States.

Examines the future of the fusion science research program, according to the fusion community. Fusion science's recent setbacks; Cancellation of Burning Plasma Experiment (BPX); Near-term research goals; Plans for the Tokamak Physics Experiment (TPX), a steady state tokamak; Support for TPX; Revised plans for International Thermonuclear Experimental Reactor (ITER); Fusion's budgetary uncertainties.

Reports on the problems facing the national database at Brookhaven National Laboratory, which, after spending years begging researchers to submit data on the structure of protein or nucleic acid molecules, now has a backlog of over 300 protein structures, a year's worth of work, to process. How situation was reversed; Impact of rapidly developing technology on database; Improvements in data collection techniques; Criticisms of database director, Thomas Koetzle.

Examines the status of the National Institutes of Health's (NIH) two-year investigation of AIDS researcher Robert Gallo whose lab is charged with either accidentally taking or stealing a virus, called LAV and used as the basis of Gallo's AIDS blood test, from the Paris-based Pasteur Institute. Details of NIH's Office of Scientific Integrity (OSI) investigation into suspect data from Gallo's lab; Criticisms of OSI's handling of investigation report; Gallo's response.

Discusses the findings in a draft report of the National Institutes of Health (NIH) investigation of a 1984 `Science' paper by AIDS researcher Robert Gallo and his former colleague, Mikulas Popovic, despite the secrecy concerning the report by the NIH's Office of Scientific Integrity (OSI). Accusations of Popovic's scientific misconduct; Criticism of report itself; More.

Highlights the details of the case in which a leaked report by the Office of Scientific Inquiry accused Tufts immunologist Thereza Imanishi-Kari of fabricating data in a 1986 `Cell' paper she had co-authored with Nobel laureate David Baltimore. Imanishi-Kari's rebuttal; Allegations by Margot O'Toole; Split in the scientific community; Scientific results.

Reports that a federal judge in Wisconsin has thrown out the procedures used by the National Institutes of Health's (NIH) Office of Scientific Integrity. The NIH may have to suspend investigations currently in progress. INSET: More woes for Gallo (AIDS researcher Robert C. Gallo)..

Examines the figures of scientific papers not cited in other work within five years of their publication as possible evidence that the papers aren't significant, or that scientific journals are printing too much work. Comments on figures by prominent scientists; Publishing industry's responsibility; Role of academic promotion system; Further analysis of data.

Looks at some of the `academic pork' projects that made it into the recent 1991 budgets for the Departments of Energy, Defense and Agriculture. Condemnation of pork-barrel funding for research facilities; Effects on military budget; Other pork projects; USDA competitive grants program budget cuts; Possible solutions. INSET: Alaskan pork: Aurora fantasia, by P. Selvin..

Summarizes research into useful materials that might be made from the ceramic compounds that make up the current family of high-temperature superconductors (HTS) now that critical temperatures (Tc) appear stalled at about 125 K. Research into Y123; `Melt-textured processing;' Improvement in mechanical properties; `Macro-composite' approach; Superconducting electronics; Laser ablation; Superconducting field-effect theory. INSET: HTS theory: Where's the beef?, by D.P.H..

Summarizes the protest by the administration of the Massachusetts Institute of Technology (MIT) over the National Science Foundation (NSF) peer-review process used to select a competitor, Florida State University, as the recipient of a grant fora new national magnet lab. Reasons for MIT's criticisms; Technical superiority; Funding questions; Faculty recruitment; User service; International competitiveness.

Discusses the continued rising costs of the Superconducting Super Collider (SSC) which is still enjoying strong Congressional support. Department of Energy (DOE) Independent Cost Estimating Group (ICE) estimate; Reasons for Congressional support; Private investors; Foreign investors; Concern over quadrupole magnet design.

Reports on recommendations by technology experts, including John Shattuck, a vice president for government, community, and public affairs at Harvard University, for liberalizing burdensome information export controls, put in place by the Reagan administration.