Search Publications
An overview of radar soundings of the martian ionosphere from the Mars Express spacecraft
Gurnett, D. A.; Persoon, A. M.; Averkamp, T. F. +10 more
The Mars Express spacecraft carries a low-frequency radar called MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) that is designed to study the subsurface and ionosphere of Mars. In this paper, we give an overview of the ionospheric sounding results after approximately one year of operation in orbit around Mars. Several types of…
Impact effects from small size meteoroids and space debris
Drolshagen, Gerhard
When the impact risk from meteoroids and orbital debris is assessed the main concern is usually structural damage. With their high impact velocities of typically 10 20 km/s millimeter or centimeter sized objects can puncture pressure vessels and other walls or lead to destruction of complete subsystems or even whole spacecraft. Fortunately chances…
Furthering our understanding of electrostatic solitary waves through Cluster multispacecraft observations and theory
Gurnett, D. A.; Lakhina, G. S.; Tsurutani, B. T. +9 more
Nonlinear isolated electrostatic solitary waves (ESWs) are observed routinely at many of Earth’s major boundaries by the Wideband Data (WBD) plasma wave receivers that are mounted on the four Cluster satellites. The current study discusses two aspects of ESWs: their characteristics in the magnetosheath, and their propagation in the magnetosheath a…
Solar flare forecasting model supported with artificial neural network techniques
Li, R.; Wang, H. N.; Cui, Y. M. +2 more
Nowadays operational models for solar activity forecasting are still based on the statistical relationship between solar activity and solar magnetic field evolution. In order to set up this relationship, many parameters have been proposed to be the measures. Conventional measures are based on the sunspot group classification which provides limited…
Recent advances in observations and modeling of the solar ultraviolet and X-ray spectral irradiance
Woods, Thomas N.
There have been significant, recent advances in understanding the solar ultraviolet (UV) and X-ray spectral irradiance from several different satellite missions and from new efforts in modeling the variations of the solar spectral irradiance. The recent satellite missions with solar UV and X-ray spectral irradiance observations include the X-ray S…
A statistical study of hot flow anomalies using Cluster data
Dandouras, I.; Daly, P. W.; Facskó, G. +3 more
Hot flow anomalies (HFAs) are studied using observations of the RAPID suprathermal charged particle detector, the FGM magnetometer, and the CIS plasma detector aboard the four Cluster spacecraft. Previously, we studied several specific features of tangential discontinuities on the basis of Cluster measurements in February-April 2003. In this paper…
The plasma sheet and boundary layers under northward IMF: A multi-point and multi-instrument perspective
Escoubet, C. P.; Pitout, F.; Zhang, T. L. +23 more
During conditions of northward interplanetary magnetic field (IMF), the near-tail plasma sheet is known to become denser and cooler, and is described as the cold-dense plasma sheet (CDPS). While its source is likely the solar wind, the prominent penetration mechanisms are less clear. The two main candidates are solar wind direct capture via double…
Results from the ESA SREM monitors and comparison with existing radiation belt models
Nieminen, P.; Hajdas, W.; Bühler, P. +3 more
The Standard Radiation Environment Monitor (SREM) is a simple particle detector developed for wide application on ESA satellites. It measures high-energy protons and electrons of the space environment with a 20° angular resolution and limited spectral information. Of the ten SREMs that have been manufactured, four have so far flown. The first mode…
Heterogeneous solid/gas chemistry of organic compounds related to comets, meteorites, Titan, and Mars: Laboratory and in lower Earth orbit experiments
Szopa, C.; Cottin, H.; Coll, P. +14 more
To understand the evolution of organic molecules involved in extraterrestrial environments and with exobiological implications, many experimental programs in the laboratory are devoted to photochemical studies in the gaseous phase as well as in the solid state. The validity of such studies and their applications to extraterrestrial environments ca…
Supernova remnants with magnetars: Clues to magnetar formation
Vink, Jacco
In this paper I discuss the lack of observational evidence that magnetars are formed as rapidly rotating neutron stars. Supernova remnants containing magnetars do not show the excess of kinetic energy expected for such a formation scenario, nor is there any evidence for a relic pulsar wind nebula. However, it could be that magnetars are formed wit…