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With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans.Electronic supplementary materialThe online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

We present three solar wind shock events that all occurred at times when Advanced Composition Explorer was near L1 and WIND was in front of the bow shock. We use a 1.5‐D MHD (magnetohydrodynamic) numerical model and the well known MVAB‐0 time‐shifting algorithm to propagate these events from Advanced Composition Explorer to the location of WIND. The results of these two methods are compared to WIND observations. We find that the 1.5‐D numerical model reproduces some important features in the WIND data that are not reflected in the time‐shifted results. We believe that 1.5‐D numerical simulations could supplement traditional time‐shifting methods in some circumstances for time‐shifting solar wind data to the bow shock. Key Points: We use a 1.5‐D ideal MHD numerical model to propagate three solar wind shock events measured at L1 to near the Earth's bow shockWe compare the numerically propagated solar wind data and pointwise time‐shifted dataWe find that the numerically propagated data capture aspects of measurements near the Earth that the time shift does not [ABSTRACT FROM AUTHOR]

The geoeffectiveness of solar wind shocks depends on angle with respect to the Sun‐Earth line, with highly angled solar wind shocks being less geoeffective than nearly frontal solar wind shocks. However, it is unclear whether this holds for the orientation of structures in nonshocked solar wind. In this paper, we perform a mutual information analysis of 18 years of in situ solar wind and ground magnetometer data in order to investigate the effects of solar wind phase front orientation on solar wind geoeffectiveness (indicated by SuperMAG SME, the SuperMAG enhanced version of the AE index). Since geomagnetic response is strongly influenced by interplanetary magnetic field (IMF) Bz, and IMF Bz affects phase front orientation, we use conditional mutual information to account for the effect of Bz on geomagnetic activity. In contrast to what has been found for solar wind shocks, we find that during times of IMF Bz > 0, phase fronts aligned with the average Parker spiral direction (45° azimuth, 0° inclination) tend to be associated with higher geomagnetic activity (SME > 500 nT) than would be expected if IMF Bz and phase front orientation quantities were unrelated. During times of IMF Bz < 0, there is no connection between solar wind phase front orientation and geomagnetic activity (SME). We believe that Parker spiral‐aligned phase fronts being associated with higher geomagnetic activity during times of IMF Bz > 0 is due to constant phase front orientation allowing for more efficient energy transfer either through viscous interaction or high‐latitude reconnection. Key Points: Solar wind phase front orientation geoeffectiveness is quantified using information theoryWhen Bz > 0, solar wind phase fronts are more often highly geoeffective when aligned with the average Parker spiral directionWhen Bz < 0, there is no connection between solar wind phase front orientation and solar wind geoeffectiveness [ABSTRACT FROM AUTHOR]