The purpose of the project is to calculate particle spectra and radiation doses on-board satellites at low-Earth orbits.

Calculations are based on proton spectra obtained from geosynchronous satellite measurements of energetic particle fluxes. Spectrum polinomial approximation was used to reproduce the proton fluxes. Vertical cutoff rigidity at a given point at the orbit of low-altitude satellite is calculated by R. Nymmik model, dependent on Kp-index of geomagnetic activity.

Transmittance function can be also calculated as a probability to "meet " the particles of a given rigidity during the next two passes of LEO satellite around the Earth.

Date & Time Universal Time: : Date: UT: : Orbit parameters   |   Select Satellite Mean motion: Inclination (i): Right Ascension of ascending node: Eccentricity (e): Argument of perigee at epoch (ω): Mean anomaly from perigee at epoch (M0): Orbit decay rate: Display results: Proton spectra at GEO Proton spectra at LEO Transmittance Function

Working with the left-side menu Select the satellite and the time moment. If you didn't find the satellite in the list, you can input the satellite name or NORAD number. Orbit parameters will be calculated by TLE data. You can also enter the orbit parameters directly after switching from Satellite to the Orbit Parameters form. Select output data you need (GEO Spectrum, LEO Spectrum, Transmittance Functions).

You can help the project by sending your suggestions and bug-reports to the collective of the authors:

• Vladimir Kalegaev, the head of the project
• Rikho Nymmik, the author of the theoretical spectra calculating
• Boris Yushkov, the author of the Transmittance calculating
• Wera Barinova & David Parunakyan, graphics, plots, programming and design of the page.