[1] For low values of the solar wind electric field, the response of the polar cap potential is essentially linear, but at high values of VB s , the polar cap potential saturates and does not increase further with increasing VB s . On the other hand, the ring current injection rate does increase linearly with VB s and shows no evidence of saturating. If enhanced convection is the origin of the ring current, this poses a paradox. How can the polar cap potential, and thus convection, saturate when the ring current does not? We examine a possible explanation based on the reexamination of the Burton equation by Vasyliunas (2006). We show that this explanation is not a viable solution to the paradox since it would require a changing polar cap flux, and we demonstrate that the polar cap flux saturates (at around 1 GWb) as the polar cap potential saturates. Instead, we argue that during storms a quasi-steady reconnection region forms in the tail near the Earth. This reconnection region moves closer to the Earth for higher values of solar wind B s , although the polar cap potential, the dayside merging and nightside reconnection rates, and the amount of open flux do not change much as a function of B s once the polar cap potential has become saturated. As the neutral line moves closer, the volume per unit magnetic flux in the closed field line region is less. Flux tubes leaving the reconnection region in general have lower PV g as B s increases, and lower PV g flux tubes can penetrate deeper into the inner magnetosphere, leading to a corresponding greater injection of particles into the inner magnetosphere. Thus a reconnection region that is closer to Earth is more effective in creating a strong ring current. This leads to a continued dependence of the ring current injection rate on VB s , although the polar cap potential has saturated.
Abstract. We examine the distribution and propagation of energy in the plasma sheet and lobes using observations and simulations for three substorms. The substorms occurred on 9 March 1995, 10 December 1996, and 27 August 2001 and have been simulated using the Lyon-Fedder-Mobarry magneto-hydrodynamic code. All three events occur over North America and show a clear substorm current wedge over the ground magnetometer chains of Alaska, Canada, and Greenland. The three simulations show the thinning of the plasma sheet during the growth phase of the event and an increase in the relative amount of thermal energy due to the compression of the plasma sheet. Generally, the total lobe energy, polar cap flux, and lobe magnetic field strength simultaneously increase during the growth phase, and polar cap flux and total lobe energy only start dropping at substorm onset, as measured by the CANOPUS magnetometer chain. Starting at time of onset and continuing throughout the expansion phase a transfer of magnetic energy from the lobes into the plasma sheet occurs, with the increase in the plasma sheet energy ranging from 30-40% of the energy that is released from the lobes.
In the recent years, the "Program for INteractive Timeline Analysis" PINTA, developed at the German Space Operation Center (GSOC), was continuously improved and experienced several evolution steps. PINTA is a GUI application running on Windows-based computer systems, whose main purpose is to serve as the anchor tool for a mission planning operation's engineer when generating, modifying or analysing a mission timeline. This is supported by calling automatic planning algorithms of the embedded generic planning library "PLAnningTOol" PLATO, using input of the embedded orbit propagation and event calculation library "SpaceCraft Orbit and GroundTrack Analysis Tool" SCOTA, or its expandability through plugins.PINTA is the generic basis of many semi-automated mission planning systems for past, current and future spacecraft projects operated at GSOC. It is used or has been used for the missions Grace, TET-OOV, FireBird, Grace-FollowOn, Eu:CROPIS and is currently prepared for CubeL. Furthermore, PINTA serves as the timeline analysis tool for validating the TerraSAR-X/TanDEM-X mission planning system.The variety of use cases was further extended to support Launch and Early Orbit Phases (LEOPs) in its special "SoEEditor" configuration as the new generic editing tool for the so-called "Sequence of Events". It was successfully used for the satellites Biros, HAG-1, PAZ, Grace-FollowOn 1 & Grace-FollowOn 2, Eu:Cropis, EDRS-C and is currently in preparation for EnMAP. In addition to LEOP's, the SoEEditor was also capable of supporting the constellation maneuvers for the TerraSAR-X/TanDEM-X mission.Besides all these use cases, the paper at hand will especially describe how PINTA was even further extended to not only tackle spacecraft-based but also ground-based scheduling. On the one hand it serves as an "On-Call Tool" to support the on-call shifts by automatically generating conflict-free role-based shift plans for all subsystems by considering various constraints like person outages, working hours, role-conflicts, etc… The plan can then be further adapted manually to cope with user change-requests. On the other hand it is used as a "Multi-Mission-Control-Room-and-pass-Scheduler" (MuMiCoRoS) to coordinate the ground-station booking of all LEO (low-earth orbit) satellites: TerraSAR-X, TanDEM-X, TET, Biros, Grace-FollowOn 1 & 2 and Eu:CROPIS. In order to avoid ground-station and operator conflicts between the missions, an automatic and combined plan for all satellites is generated which can then be further modified manually if necessary.As another use case, PINTA (a.k.a. GPT; Galileo Planning Tool) supports the Galileo Service Operation (GSOp). The planning process involves three timelines: a Short-Term Plan (STP), covering the next ten days, two Mid-Term Plans (MTP) for the Operational (OPE) and the Validation (VAL) chain), covering the next 15 weeks, and a Long-Term Plan (LTP), covering the next 15 months. The activities in these timeframes cover all subsystems of Galileo: Flight Ops, Control segment, Mission segment, remote sit...
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