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Space physics is the study of Earth's home in space. Elements of space physics include how the Sun works from its interior to its atmosphere, the environment between the Sun and planets out to the interstellar medium, and the physics of the magnetic barriers surrounding Earth and other planets. Space physics is highly relevant to society. Space weather, with its goal of predicting how Earth's technological infrastructure responds to activity on the Sun, is an oft‐cited example, but there are many more. Space physics has important impacts in formulating public policy. Space physics is the study of Earth's home in spaceSpace physics is broadly relevant to society; space weather is only one of many impactsSpace physics impacts policy decisions in many arenas, from homeland security to space exploration

Inability to maintain blood glucose concentrations (BG) to a normal range is a common complication of prematurity and stress in neonatal intensive care units (NICUs). STAR (Stochastic TARgeted) glycaemic control uses physiological models to capture and predict patient glycaemic behaviour, and thus dose insulin safely and effectively for tight glycaemic control. STAR in the NICU has in past been based on a simple NICU model. In this study, clinical data is used to identify and validate insulin kinetic parameters of the more physiologically descriptive NICING (Neonatal Intensive Care Insulin-Nutrition-Glucose) model. C-peptide, plasma insulin and BG from a cohort of 41 extremely pre-term (median age 27.2 [26.2 - 28.7] weeks) and very low birth-weight infants (median birth weight 839 [735 - 1000] g) was used alongside C-peptide kinetic models to identify model parameters associated with insulin kinetics in the NICING model. These kinetic parameters in the NICING model were validated by fitting the model to a cohort of 160 glucose, insulin, and nutrition data records from extremely premature infants from two different NICUs. The model fits data and predicts changes in BG in a manner similar to the previous NICU model, indicating that it will perform safely and effectively in the clinical setting. However, the NICING model is more physiologically descriptive, capturing more insulin kinetics and allowing consistency with existing adult ICU glycaemic control protocols and other diabetes models.

The Voyager1 spacecraft is currently in the vicinity of the heliopause, which separates the heliosphere from the local interstellar medium. There has been a precipitous decrease in particles accelerated in the heliosphere and a substantial increase in galactic cosmic rays (GCRs). The evidence is unclear, however, as to whether Voyager1 has crossed the heliopause into the local interstellar medium or remains within the heliosheath. In this Letter we propose a test that will determine whether Voyager 1has crossed the heliopause: If Voyager 1remains in the heliosheath, the high densities observed must be due to compressed solar wind, with the consequence that Voyager 1will encounter another current sheet, where the polarity of the magnetic field reverses. Voyager 1observations can be used to predict that the next current sheet crossing is likely to occur during 2015. Voyager 1 is predicted to encounter the heliospheric current sheet againSuch an encounter would demonstrate that Voyager 1 remains in the heliosheath

We investigate the characteristics and solar origins of a subpopulation of the solar wind that possesses extreme values of proton flux. Ulysses observations including solar wind magnetic flux, proton flux, number density and velocity, and ionic composition are examined in this study. We find that the departures of solar wind proton flux from its constancy occur for time intervals leading up to and encompassing the past two solar minima, and the extreme‐proton‐flux wind possesses the following characteristics: (1) it generally originates from sources middle‐distant from the Heliospheric Current Sheet (HCS); (2) it is associated with a broad range of velocities and electron temperatures but excludes very fast/cold wind; (3) it exhibits anticorrelation between electron temperature and proton velocity, as does the rest of the solar wind; (4) it has extreme proton density values relative to the rest of the solar wind; and (5) the extreme‐high‐proton‐flux wind has radial component of open magnetic flux (Br) greater than the rest of the solar wind, and both extreme‐high and extreme‐low wind do not possess the lowest values of Br flux. Comparing with SOHO EIT 195 Å coronal images, we find the observed extreme‐proton‐flux wind has temporal and spatial coincidence with the appearance of low‐latitude coronal holes present in the recent two solar minima; the magnetic field lines extrapolated by the Potential Field Source Surface model confirm there are coronal pseudostreamer structures involved. So we propose that these extreme‐proton‐flux winds can be associated with mid‐ to low‐latitude coronal holes and “pseudostreamer” structures. Extreme‐proton‐flux solar wind was seen at middle latitudes in two solar minima.This wind has unusual properties compared with the rest of the wind.This wind can be associated with

Abstract—The plasma environment at Mercury is a rich laboratory for studying the interaction of the solar wind with a planet. Three primary populations of ions exist at Mercury: solar wind, magnetospheric, and pickup ions. These pickup ions are generated through the ionization of Mercury's exosphere or are sputtered particles from the Mercury surface. A comprehensive mission to Mercury, such as MESSENGER (MErcury: Surface, Space ENvironment, GEochemistry, Ranging), should include a sensor that is able to determine the dynamical properties and composition of all these plasma components. An instrument to measure the composition of these ion populations and their three‐dimensional velocity distribution functions must be lightweight, fast, and have a very large field of view.

The transition between coronal hole associated fast solar wind and slow solar wind is studied using data from the high resolution mass spectrometer SWICS on ACE. We discuss the data in the framework of a recent theory about the global heliospheric magnetic field and conclude that the data are consistent with magnetic connections between field-lines in the fast and in the slow wind.

Coronal hole boundaries are the interfaces between regions where the coronal magnetic field contains a significant component which is open into the heliosphere and regions where the field is primarily closed. It is pointed out that there are constraints on the magnetic field which opens into the heliosphere that must be satisfied in the corona: it must come into pressure equilibrium in the high corona, and the component of the field which connects to the polar regions of the Sun must differentially rotate. A model is presented in which satisfying these constraints determines which field lines are open and which are closed, and thus where the polar coronal hole boundaries occur. Some of the consequences of this model are discussed.

The 28th ESLAB Symposium marks the beginning of the sprint of the Ulysses mission to the very high heliographic latitudes and the pole-to-pole passage. The more than twenty-year quest to understand the Sun and the heliosphere in three dimensions is about to be realized. It is perhaps worthwhile, as we are poised to begin this journey, to ask how history is likely to judge this mission, or equivalently: what questions need to be answered so that the judgment will be kind?

The Solar Wind and Suprathermal Ion Composition Experiment (SMS) on WIND is designed to determine uniquely the elemental, isotopic, and ionic-charge composition of the solar wind, the temperatures and mean speeds of all major solar-wind ions, from H through Fe, at solar wind speeds ranging from 175 kms-1 (protons) to 1280 kms-1 (Fe+8), and the composition, charge states as well as the 3-dimensional distribution functions of suprathermal ions, including interstellar pick-up He+, of energies up to 230 keV/e. The experiment consists of three instruments with a common Data Processing Unit. Each of the three instruments uses electrostatic analysis followed by a time-of-flight and, as required, an energy measurement. The observations made by SMS will make valuable contributions to the ISTP objectives by providing information regarding the composition and energy distribution of matter entering the magnetosphere. In addition SMS results will have an impact on many areas of solar and heliospheric physics, in particular providing important and unique information on: (i) conditions and processes in the region of the corona where the solar wind is accelerated; (ii) the location of the source regions of the solar wind in the corona; (iii) coronal heating processes; (iv) the extent and causes of variations in the composition of the solar atmosphere; (v) plasma processes in the solar wind; (vi) the acceleration of particles in the solar wind; and (vii) the physics of the pick-up process of interstellar He as well as lunar particles in the solar wind, and the isotopic composition of interstellar helium.

We report initial measurements from the ULECA sensor of the Max-Planck-Institut/University of Maryland experiment on ISEE-1. ULECA is an electrostatic deflection — total energy sensor consisting of a collimator, deflection analyzer and an array of solid state detectors. The position of a given detector, which determines the energy per charge of an incident particle, together with the measured energy determine the particle's charge state. We find that a rich variety of phenomena are operative in the transthermal energy regime (~10 keV/Q to ~100 keV/Q) covered by ULECA. Specifically, we present observations of locally accelerated protons, alpha particles, and heavier ions in the magnetosheath and upstream of the Earth's bow shock. Preliminary analysis indicates that the behavior of these locally accelerated particles is most similar at the same energy per charge.

Recent observations from the Voyager spacecraft have suggested that the spectrum of the anomalous cosmic ray component is relatively steep at the termination shock, which is believed to be responsible for accelerating these particles. This conclusion argues that the termination shock must be weak, which in turn requires that the upstream Mach number in the solar wind must be quite low, ~2.4. It is pointed out that such conditions are unlikely to prevail at all locations along the shock front. However, it is possible for such conditions to exist at the interface between high speed streams at high heliographic latitudes and the region at low latitudes where high and low speed streams have interacted and come into equilibrium. This discussion suggests a preferred location for the injection of the anomalous component into the shock acceleration process.

The theory of shock acceleration of energetic particles is briefly discussed and reviewed with an emphasis on clarifying the apparent distinction between the ‘V × B’ and ‘Fermi’ mechanisms. Attention is restricted to those situations in which the energetic particles do not themselves influence the given shock structure. In particular, application of the theory to the acceleration of energetic particles in corotating interaction regions (CIR) in the solar wind is presented. Here particles are accelerated at the forward and reverse shocks which bound the CIR by being compressed between the shock fronts and magnetic irregularities upstream from the shocks, or by being compressed between upstream irregularities and those downstream from the shocks. Particles also suffer adiabatic deceleration in the expanding solar wind, an effect not included in previous shock models for acceleration in CIRs. The model is able to account for the observed exponential spectra at Earth, the observed behavior of the spectra with radial distance, the observed radial gradients in the intensity, and the observed differences in the intensity and spectra at the forward and reverse shocks.

The global processes that determine cosmic ray modulation are reviewed. The essential elements of the theory which describes cosmic ray behavior in the heliosphere are summarized, and a series of discussions is presented which compare the expectations of this theory with observations of the spatial and temporal behavior of both galactic cosmic rays and the anomalous component; the behavior of cosmic ray electrons and ions; and the 26-day variations in cosmic rays as a function of heliographic latitude. The general conclusion is that the current theory is essentially correct. There is clear evidence, in solar minimum conditions, that the cosmic rays and the anomalous component behave as is expected from theory, with strong effects of gradient and curvature drifts. There is strong evidence of considerable latitude transport of the cosmic rays, at all energies, but the mechanism by which this occurs is unclear. Despite the apparent success of the theory, there is no single choice for the parameters which describe cosmic ray behavior, which can account for all of the observed temporal and spatial variations, spectra, and electron vs. ion behavior.

The behavior of the anisotropy during solar cosmic-ray events is discussed in terms of a simple model in which cosmic-ray particles propagate along the mean interplanetary magnetic field, undergoing pitch-angle scattering. It is shown that a generalized form of the telegraph equation should be used when the anisotropy is large (i.e. greater than 30%), but that the usual diffusion equation is adequate otherwise. The behavior of the anisotropy during the decay phase of solar cosmic-ray events is then considered, and several effects which can give rise to a small persisting anisotropy are described. Finally, observations of solar cosmic-ray anisotropies following flares are reviewed and it is concluded that the simplified mathematical treatment presented here adequately describes some of the general features of the behavior of the anisotropy, but does not provide a detailed quantitative description of the particle behavior, especially during the highly anisotropic phase of an event.

A model is proposed to explain the transport of energetic protons in the solar corona. The particles are assumed to undergo an enhanced gradient-B drift along thin current sheets separating discontinuous field structures in the corona. These discontinuities may represent the extension into the corona of photospheric granular and supergranular cell boundaries. We have made a quantitative analysis of this process by assuming that the particle propagation can be described by a diffusion equation. Comparison of predictions of the model with cosmic ray observations at ~ 1 AU provide some support for the model.

Approximate equations which describe the behavior of cosmic rays in the interplanetary medium under suitable conditions are used to make comparisons between observations and theoretical predictions of radial gradients and radial anisotropies. In the high energy region there appear to be no inconsistencies between theory and observations. In the low energy region it is shown that theoretical predictions of the radial anisotropy expected from large radial gradients of the intensity are not inconsistent with observed radial anisotropies. However, in the latter case there are other inconsistencies, which suggest that some aspects of the observations or of the theory (or both) are unsatisfactory.

Describes the Green Machine, a composter built by Jim Fisk, which is capable of handling a large amount of organic waste and is itself made from recycled parts. How the composter works; `Raw' mix for bacteria; Rotation of pile; Ease of use.