Simulation of electron environment in space at 36,000 km

Dec 09, 2013

A spacecraft at near-Earth orbit is continuously bombarded by charged particles. Finnish Meteorological Institute has developed a unique model that simulates electron environment in the near-Earth space.

Finnish Meteorological Institute's new model specifies the electron at any orbit where important satellites are moving. FMI' s new IMPTAM (Inner Magnetosphere Particle Transport and Acceleration Model) model is a unique tool and the only one in Europe. "Specifying the electron flux at any satellite orbit, we will be able to provide satellite operators the critical information for surface charging of satellite materials", says the main developer of the IMPTAM model, FMI's researcher Dr. Natalia Ganushkina.

At present, there are about 1000 operational satellites at different orbits in the near-Earth and all of them pass through the regions where the can vary significantly with location. All the variability is imposed by the activity of the Sun.

Electrons with these energies constitute one of the most important parts of the radiation environment in the near-Earth space. First, they are responsible for discharges on the surface of the outer spacecraft layers that can cause significant damage and spacecraft anomalies. Second, they are accelerated to much higher energies of megaelectronvolts and populate the Earth's radiation belts which are from the radiation hazard viewpoint the two most critical regions around the Earth.

Main drivers of transport and acceleration of electrons with energies of 50 to 150 kiloelectronvolts (keV) to (36000 km above the Earth) in space. Electrons come to geostationary orbit from the areas in space located at about 10 Earth Radii (1 Earth Radius is equal to 6400 km) from the Earth in the direction away from the Sun. They move towards the Earth not in empty space but in magnetic and electric fields whose presence was established from observations. These magnetic and electric fields guide electrons, and if they change, electrons move differently. Since we do not have satellites in every point in space to tell us what are the magnitudes of the fields, we need to use models for these fields.

A very good agreement is achieved between the observed electrons in form of electron fluxes measured by several satellites at geostationary orbit and our model electron fluxes at the same locations as satellites. The main factor was found to be the inclusion of small-scale electric fields related to reconfiguration of electric and magnetic fields during substorms, phenomena which occurs in our space very often, almost every day and last 1-3 hours. Substorms are responsible for spectacular aurora displays which we can see at high latitudes. The good agreement indicates that our model contains the necessary physical processes correctly, and can be used for other orbits, not only for geostationary.

The IMPTAM development and improvement is underway the SPACECAST project (http://fp7-spacecast.eu) funded by the European Union Seventh Framework Programme. The present study which is mostly scientific is the base for the adaptation of scientific models to operational ones in near future.

Explore further: Latest GOES-R instrument cleared for installation onto spacecraft

More information: Ganushkina, N. Y., O. A. Amariutei, Y. Y. Shprits, and M. W. Liemohn (2013), Transport of the plasma sheet electrons to the geostationary distances, Journal of Geophysical Research, Space Physics, 118, DOI: 10.1029/2012JA017923

add to favorites email to friend print save as pdf

Related Stories

ESA SWARMing Earth's magnetic field

Nov 25, 2013

ESA's three-satellite Swarm constellation was lofted into a near-polar orbit by a Russian Rockot launcher this afternoon. For four years, it will monitor Earth's magnetic field, from the depth of our planet's ...

Recommended for you

NASA's space station Robonaut finally getting legs

5 hours ago

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Sun emits a mid-level solar flare

Apr 18, 2014

The sun emitted a mid-level solar flare, peaking at 9:03 a.m. EDT on April 18, 2014, and NASA's Solar Dynamics Observatory captured images of the event. Solar flares are powerful bursts of radiation. Harmful ...

Impact glass stores biodata for millions of years

Apr 18, 2014

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...

The importance of plumes

Apr 18, 2014

The Hubble Space Telescope is famous for finding black holes. It can pick out thousands of galaxies in a patch of sky the size of a thumbprint. The most powerful space telescope ever built, the Hubble provided ...

User comments : 0

More news stories

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Cosmologists weigh cosmic filaments and voids

(Phys.org) —Cosmologists have established that much of the stuff of the universe is made of dark matter, a mysterious, invisible substance that can't be directly detected but which exerts a gravitational ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.