Space weather and space anomalies

A large database of anomalies, registered by 220 satellites in different orbits over the period 1971-1994 has been compiled. For the first time, data from 49 Russian Kosmos satellites have been included in a statistical analysis. The database also contains a large set of daily and hourly space weather parameters. A series of statistical analyses made it possible to quantify, for different satellite orbits, space weather conditions on the days characterized by anomaly occurrences. In particular, very intense fluxes (>1000 pfu at energy >10 MeV) of solar protons are linked to anomalies registered by satellites in high-altitude (>15000 km), near-polar (inclination >55°) orbits typical for navigation satellites, such as those used in the GPS network, NAVSTAR, etc. (the rate of anomalies increases by a factor ~20), and to a much smaller extent to anomalies in geostationary orbits, (they increase by a factor ~4). Direct and indirect connections between anomaly occurrence and geomagnetic perturbations are also discussed

Effect of the Space on Operation of Satellites

The database created by us based on malfunctions of more than 300 spacecraft differently orbited from 1971 to 1994, which formed the basis for statistically analyzing the effect of the space on operation of satellites, is described. Data on 49 satellites of the Cosmos series have been included in an analysis for the first time. The database also includes the large set of daily and hourly values of the space weather parameters. A statistical analysis based on more than 6000 malfunctions has made it possible to obtain the quantitative characteristics of the relations between malfunctions and the space weather factors. In particular, very intense solar proton fluxes (with energy > 10 MeV) cause an almost 20-fold increase in the number of failures in high polar orbits and much weaker affect geostationary and low polar orbits. Enhanced electron fluxes (>2 MeV) increase the number of failures on geostationary and low-orbiting polar satellites but almost do not affect high-orbiting polar satellites. Direct and indirect relations between malfunctions and geomagnetic disturbance are discussed

Spacecraft operational anomalies and space weather impact hazards

Satellite anomaly data in the period 1971–1994 were analyzed in the search of possible influence of different space environmental parameters. The database was created by combining, beyond the malfunction information, various characteristics of space weather: geomagnetic activity indexes, fluxes and fluencies of electrons and protons at different energy, solar wind characteristics and other solar, interplanetary and geophysical data. Satellites were divided into several groups according to the orbital characteristics (altitude and inclination). It was found, that the relation of satellite malfunctions to the environmental parameters is different for various orbits. In particular, very intense fluxes (>1000 pfu at energy >10 MeV) of solar protons are linked to anomalies registered by satellites in high-altitude (>15,000 km) near-polar (inclination >55°) (the rate of anomalies increases by a factor ~20), and to a much smaller extent to anomalies in geostationary orbits (they increase by a factor ~4). The efficiency in producing anomalies is found to be negligible for proton fluencies 10 MeV. Elevated fluxes of energetic (>2 MeV) electrons >10^8 (cm^2 day sr)^-1 are observed by GOES on days with satellite anomalies occurring at geostationary and low-altitude (55°) orbits. These elevated fluxes are not observed on days of anomalies registered in high-altitude near-polar orbits. Connections between anomaly occurrence and geomagnetic perturbations are also discussed. © 2005 COSPAR. Published by Elsevier Ltd. All rights reserved

Space Weather Conditions and Spacecraft Anomalies in Different Orbits

A large database of anomalies, registered by 220 satellites in different orbits over the period 1971--1994, has been compiled. For the first time, data of 49 Russian Kosmos satellites have been included in a statistical analysis. The database also contains a large set of daily and hourly space weather parameters. A series of statistical analyses made it possible to quantify, for different satellite orbits, space weather conditions in the days characterized by anomaly occurrences. In particular, very intense fluxes (>1000 particles cm^-2 s^-1 (pfu) at energy >10 MeV) of solar protons are linked to anomalies registered by satellites in high-altitude (>15,000 km) near-polar (inclination >55°) orbits typical for navigation satellites such as those used in the GPS network, NAVSTAR, etc. (the rate of anomalies increases by a factor of ~20) and to a much smaller extent to anomalies in geostationary orbits (the rate increases by a factor of ~4). The efficiency in producing anomalies is found to be negligible for proton fluences 10 MeV. Elevated fluxes of energetic (>2 MeV) electrons >10^8 cm^-2 d^-1 sr^-1 are observed by GOES on days with satellite anomalies occurring at geostationary (GOES, SCATHA, METEOSAT, MARECS A, etc.) and low-altitude (<1500 km) near-polar (>55°) orbits (Kosmos, SAMPEX, etc.). These elevated fluxes are not observed on days of anomalies registered in high-altitude near-polar orbits. Direct and indirect connections between anomaly occurrence and geomagnetic perturbations are also discussed