Autoscala applied at the Ionospheric Station of Warsaw

A new ionosonde VISRC2, built at the Space Research Center of Warsaw, Poland, was installed at Warsaw (52.2 N, 21.1 E) in march 2007. The main characteristics of this ionosonde are: transmitted power 10 kW, pulse duration 100 μs, sampling period 5 μs, frequency resolution 25 kHz, and capability to distinguish ordinary and extraordinary reflections. This ionosonde, able to record the sounding only as a binary file, was not equipped with a tool to perform an automatic scaling of the recorded trace. From October 2008 Autoscala (Pezzopane and Scotto, 2005, 2007, 2008; Scotto and Pezzopane, 2007) is routinely applied to the ionograms recorded by this ionosonde

A single-station prediction model as a source of additional screen-points for PRIME model

The aim of this paper is to present a possible improvement to the global map of the f0F2 parameter obtained using statistical or any other model, by adding to it the additional screen points. The proposed method is illustrated by combining the CCIR model and a set of single points data. The comparison of the pure global CCIR model and CCIR model modified by the additional screen-points with measurements for different seasons and different solar activity is presented. The results show significant improvement of the f0F2 map

A single-station prediction model as a source of additional screen-points for PRIME model

The aim of this paper is to present a possible improvement to the global map of the f0F2 parameter obtained using statistical or any other model, by adding to it the additional screen points. The proposed method is illustrated by combining the CCIR model and a set of single points data. The comparison of the pure global CCIR model and CCIR model modified by the additional screen-points with measurements for different seasons and different solar activity is presented. The results show significant improvement of the f0F2 map

The Kriging method of ionospheric parameter f0F2 instantaneous mapping

This paper discusses the spatial variation of the ionospheric characteristic f0F2 in the PRIME area (35o-55o N,- 10°-20°E) expressed in terms of the variogram and the Kriging mapping method as modelling of an instantaneous experimental situation. It is shown that by applying this method to the real data it is possible to estimate f0F2 at any unsampled location within the restricted area with satisfactory accuracy

The Kriging method of ionospheric parameter f0F2 instantaneous mapping

This paper discusses the spatial variation of the ionospheric characteristic f0F2 in the PRIME area (35o-55o N,- 10°-20°E) expressed in terms of the variogram and the Kriging mapping method as modelling of an instantaneous experimental situation. It is shown that by applying this method to the real data it is possible to estimate f0F2 at any unsampled location within the restricted area with satisfactory accuracy

November 2004 space weather events: Real-time observations and forecasts

Space weather events with their solar origin and their distribution through the heliosphere affect the whole magnetosphere-ionosphere-Earth system. Their real-time monitoring and forecasting are important for science and technology. Here we discuss one of the largest space weather events of Solar Cycle 23, in November 2004, which was also one of the most difficult periods to forecast. Nine halo coronal mass ejections (CMEs), interacting on their way through the interplanetary medium and forming two geoeffective interplanetary structures, exemplify the complexity of the event. Real-time and quasi-real-time observations of the ground geomagnetic field show rapid and extensive expansion of the auroral oval to 55 in geomagnetic latitude accompanied by great variability of the ionosphere. Geomagnetically induced currents (GICs) seen in ground networks, such as power grids and pipelines, were significant during the event, although no problems were reported. Forecasts of the CME propagation, global and local ground geomagnetic activity, and ionospheric parameters, issued by several regional warning centers, revealed certain deficiencies in predictions of the interplanetary characteristics of the CME, size of the geomagnetic disturbances, and complexity of the ionospheric variations produced by this event. This paper is a collective report based on the materials presented at the splinter session on November 2004 events during the first European Space Weather Week

X-ray observations of the Crab Pulsar and Nebula with JEM–X on INTEGRAL

The Crab pulsar is the best studied rotation powered pulsar. We report the results obtained in the 3–35 keV energy band with the X-ray monitor, JEM–X, on ESAs recently launched γ-ray mission, INTEGRAL

Optimization of magnetic attitude maneuvers

The problem of minimum-time spacecraft attitude detumbling using magnetic actuators is revisited in this paper within the context of optimal control theory. The proposed closed loop control logic assumes the availability of only the ambient magnetic field measurements in the feedback loop. It is shown that the time optimality is achieved if the triple orthogonality between the torque, dipole moment and magnetic field vector is fulfilled at all times. This triple orthogonality is often neglected in current literature on the B-dot law for attitude detumblingThe Monte Carlo simulation results presented in this paper confirm the time-optimality of the control logic, and also demonstrate lower power consumption when using the proposed variant of the B-dot law, compared to the existing B-dot laws