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The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions, and simultaneously monitor the auroral response of the Northern Hemisphere ionosphere. Combining these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILE mission. Here, we describe current community efforts to prepare for SMILE, and the benefits and context various experiments that have explicitly expressed support for SMILE can offer. A dedicated group of international scientists representing many different experiment types and geographical locations, the Ground-based and Additional Science Working Group, is facilitating these efforts. Preparations include constructing an online SMILE Data Fusion Facility, the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar, and the consideration of particular observing strategies and spacecraft conjunctions. We anticipate growing interest and community engagement with the SMILE mission, and we welcome novel ideas and insights from the solar-terrestrial community.

Nutrition affects the reproductive performance of beef breeding females, but the optimal level of pasture utilisation for cow herd production in northern Australia is unknown. Historical grazing trial and reproductive performance datasets are being used to quantify the effect of pasture utilisation rates on reproductive performance. This paper describes the methodology to simulate pasture utilisation using the Mt Sanford grazing trial in the Victoria River District, Northern Territory, as a test case. This approach will be used to retrospectively estimate pasture growth and utilisation for 28 historical grazing trials representing more than 500 herd years. The resulting modelled pasture utilisation will be used in a meta-analysis of the effects of pasture utilisation on beef cattle breeder performance across northern Australia. The Mt Sanford grazing trial included eight paddocks ranging in size from 4 to 12 km2 for between 5 and 13 years. Average annual rainfall during the trial was 761mm. More than 90% of rain falls between November and March. The vegetation is a mixed tropical grassland dominated by Astrebla spp. (19%), Aristida latifolia (18%), Iseilema spp. (12%), Dichanthium spp. (11%) and Chrysopogon fallax (11%). The soil is a basalt derived vertosol. Cedar GRASP was used to model annual pasture growth and utilisation. Parameter sets from six SWIFTSYND sites at the trial site provided the start point for paddock level calibration. Interpolated climate files from SILO data drill and station rainfall provided daily climate data. Satellite derived persistent green cover was used to estimate foliage projective cover. Cattle records were used to estimate intake. Field estimated total standing dry matter (TSDM) measured at the end of the growing season (April / May) and at the end of the dry season (October) was used to calibrate paddock pasture growth (Figure 1). An independent dataset of satellite derived fractional ground green cover clipped to paddock boundari

This study investigates the interhemispheric nature of polar cap auroras via ultraviolet imaging, combined with particle data, to determine whether they occur on open or closed field lines. Data from the SSUSI (Special Sensor Ultraviolet Spectrographic Imager) instrument on board the DMSP (Defence Meteorological Satellite Program) spacecraft are examined. The DMSP spacecraft are in 90-min orbits; hence, images of each hemisphere are separated by 45min providing a good opportunity for interhemispheric study. 21 polar cap arc (PCA) events are recorded in December 2015 which have particle data from the SSJ/4 particle spectrometer associated with an arc in at least one hemisphere. Nine events are found to contain "arcs" consistent with a closed field line mechanism, that is, arcs associated with an ion signature present in both hemispheres. Six events contained arcs that were consistent with an "open field line" mechanism, that is, they were associated with electron-only precipitation. Events containing arcs that were not consistent with either of these expectations are also explored, including an example of a "non-conjugate" theta aurora and an interesting example of auroral morphology similar to a PCA which is associated with a geomagnetic storm. Seasonal effects are also investigated through a statistical analysis of PCAs over 4 months in 2015. It is found that PCAs are visible in the SSUSI data at least 20% of the time and that it is likely some are missed due to the spacecraft field of view and poor sensitivity in the summer hemisphere due to increased solar illumination.

©2016. The Authors. We present the first large-scale comparison of the spatial distribution of field-aligned currents as measured by the Active Magnetosphere and Planetary Electrodynamics Response Experiment, with the location and brightness of the average auroral oval, determined from the Imager for Magnetopause-to-Aurora Global Exploration far ultraviolet instrument. These distributions are compared under the same interplanetary magnetic field magnitude and clock angle conditions. The field-aligned currents and auroral oval drop to lower latitudes, as the interplanetary magnetic field becomes both increasingly stronger in magnitude and increasingly southward. We find that the region 2 currents are more closely aligned with the distribution of auroral UV emission, whether that be in the discrete auroral zone about dusk or in the postmidnight diffuse aurora sector. The lack of coincidence between the region 1 field-aligned currents with the auroral oval in the dusk sector is contrary to expectation.

In this paper we present two distinctly epistemological puzzles that arise for one who aspires to defend some plausible version of the precautionary principle. The first puzzle involves an application of contextualism in epistemology; and the second puzzle concerns the task of defending a plausible version of the precautionary principle that would not be invalidated by de minimis.

Jennifer Lackey's case "Creationist Teacher," in which students acquire knowledge of evolutionary theory from a teacher who does not herself believe the theory, has been discussed widely as a counterexample to so-called transmission theories of testimonial knowledge and justification. The case purports to show that a speaker need not herself have knowledge or justification in order to enable listeners to acquire knowledge or justification from her assertion. The original case has been criticized on the ground that it does not really refute the transmission theory, because there is still somebody in a chain of testifiers – the person from whom the creationist teacher acquired what she testifies – who knows the truth of the testified statements. In this paper, we provide a kind of pattern for generating counterexample cases, one that avoids objections discussed by Peter Graham and others in relation to such cases.

Since the initial discovery of cometary charge exchange emission, more than 20 comets have been observed with a variety of X???ray and UV observatories. This observational sample offers a broad variety of comets, solar wind environments and observational conditions. It clearly demonstrates that solar wind charge exchange emission provides a wealth of diagnostics, which are visible as spatial, temporal, and spectral emission features. We review the possibilities and limitations of each of those in this contribution (?? 2012 WILEY???VCH Verlag GmbH & Co. KGaA, Weinheim)

The Soft X-ray Imager (SXI) is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) mission. SMILE is a joint science mission between the European Space Agency (ESA) and the Chinese Academy of Sciences (CAS) and is due for launch in 2025. SXI is a compact X-ray telescope with a wide field-of-view (FOV) capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE orbit. SXI is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange (SWCX) process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s exosphere. SWCX provides a mechanism for boundary detection within the magnetosphere, such as the position of Earth’s magnetopause, because the solar wind heavy ions have a very low density in regions of closed magnetic field lines. The sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many hours. SXI is led by the University of Leicester in the United Kingdom (UK) with collaborating organisations on hardware, software and science support within the UK, Europe, China and the United States.