"CORONAS-PHOTON" Project

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Scientific Program and Objectives of the Project

CORONAS (Complex ORbital Observations Near-Earth of Activity of the Sun) – Russian program for study of the Sun and solar-terrestrial connections physics by series of spacecrafts, which provides launching of three solar-oriented satellites onto the near-Earth orbit.

"CORONAS-PHOTON" is the third satellite in this series. Two previous missions of the project are "CORONAS-I" (launched on March 2, 1994) and "CORONAS-F" (launched on July 31, 2001).
Launching date of “CORONAS-PHOTON” spacecraft is 2007.

"CORONAS-PHOTON" is a part of International Living With a Star Program (ILWS) .

MEPhI – Moscow Engineering Physics Institute (State University) is the main organization responsible for the scientific payload complex of the “CORONAS-PHOTON” mission.

NIIEM – Research Institute for Electromechanics (Moscow region, Istra) is the main organization responsible for the spacecraft “CORONAS-PHOTON”.

Principal Investigator of the project – Director of Astrophysics Institute at MEPhI
Dr. Yuri D. Kotov

Main goal of the project:

The investigation of energy accumulation and its transformation into energy of accelerated particles processes during solar flares; the study of the acceleration mechanisms, propagation and interaction of fast particles in the solar atmosphere; the study of the solar activity correlation with physical-chemical processes in the Earth upper atmosphere.

Objectives of the mission:

Physics of the Sun

• Determination of distribution functions of accelerated electrons, protons and nuclei and their dynamics with a high time resolution;
• Research of difference in acceleration dynamics of electrons and protons (nuclei);
• Research of distribution function variations for high energy particles (up to a few GeV);
• Research of interacting particle angular anisotropy by statistical analysis of radiation spectra and linear polarization parameters of hard X-rays;
• Study of directional effects in the region of high energy gamma radiation;
• Determination of mechanisms and requirements of electrons and protons acceleration in different flare phases, and parameters of propagation region of accelerated particles;
• Determination of elemental abundance in the region of gamma-ray production by gamma spectroscopy and capture of low energy neutrons in the solar atmosphere;
• Determination of radiation generation altitudes by observation of deuteron line weakening from limb flares;
• Determination of energy spectra view of accelerated protons and nuclei and dynamics of these spectra according to nuclear gamma-line ratio;
• Study of light elements generation (D, 3He, Li, Be) during flares;

Solar-terrestrial connections physics

• Research of chemical and isotopic compositions of nuclei accelerated in flare on the Earth orbit, and also energy and temporal parameters of flare electrons and protons;
• Monitoring of the Earth upper atmosphere by absorption of extreme ultraviolet of the quiet Sun;

Astrophysics

• Study of hard X-ray and gamma radiation from gamma-ray bursts;
• Study of X-ray radiation from the bright local sources along Ecliptic plane.

SCIENTIFIC PAYLOAD COMPLEX "PHOTON"

"CORONAS-PHOTON" SPACECRAFT

MAIN CHARACTERISTICS OF THE SPACECRAFT

Spacecraft weight, kg ………………………………………………………………………... 1900
Scientific payload weight, kg ……….......………………………………….…….......………. 540
Orbit:
• type …………………………………………………………………….………...…. circular
• height, km ……….……………………………………………………………………… 500
• inclination, deg ….….………………………………………………………………….. 82.5
Accuracy of the spacecraft longitudinal axis orientation to the Sun, arc min ….....….better than 5
Determination accuracy of the spacecraft longitudinal axis orientation on the Sun, arc min ..…. 3
Angular velocity stabilization of the spacecraft, deg/s ………………………….... less than 0.005
Accuracy of the satellite position measurement:
• along the orbit, m ………………………………………………………………….. ±1000
• by height and in transverse directions, m …………………………………………… ±500
Volume of scientific information stored per day, Gbit ………………….……………………. 8.2
Information transmitted during one communication session, Mbit ……….…..…...…….…. 2048
Nominal mission lifetime, years ……………………….………………………….…….. at least 3