Interball

Interball (Russian: Интербол) is an international space project under the leadership of the Russian Space Agency and the Space Research Institute of the Russian Academy of Sciences. The list of participants includes the Institute of Atmospheric Research of the Czech Academy of Sciences, NASA, European Space Agency, Japan Aerospace Exploration Agency, and the Canadian Space Agency. This is one of the first true multi‑satellite constellations dedicated to studying interactions between the solar wind and Earth’s magnetosphere.^[1][2]

Mission goal

The mission's main goal was to research how plasma behaves in important areas like the Earth's magnetosphere tail and the boundary between space regions, and the solar wind that moves around it.^[1]

Mission review

The research was done by launching two pairs of satellites, one big main satellite and one smaller that was the Czech built Magion sub-satellite. The first pair was launched August 3, 1995 and was called the Tail Probe (Interball-1 and Magion-4).^[1][3] The pair was placed in a long stretched out orbit that its distance from earth was about 200,000 km. The second pair was launched August 29, 1996 and was named the Auroral Probe (Interball-2 and Magion-5). It was placed in a polar orbit over the Northern Hemisphere, at an altitude of about 20,000 km high.^[1][2][4]

Both orbits are almost parallel to the ecliptic. Each probe consists of a pair satellite-sub-satellite. Sub-satellites “Magion-4” (auroral) and “Magion-5” (tail) were procured by the Institute of atmospheric Research of the Czech Academy of Sciences. The communication with “Magion-5” was interrupted August 30, 1996 and was restored May 7, 1998. The life expectancy of space vehicles is 12 years.^[1]

Results

The mission provided important information about how plasma behaves in Earth’s magnetosphere. This included measuring the magnetic field at the edge of the magnetosphere (called the magnetopause) and observing plasma waves and disturbances, like the Kelvin-Helmholtz instability that happens near the high-latitude boundaries of the magnetopause.^[5]

Related projects

GEOTAIL, WIND, POLAR, SOHO, FAST, RELICT-1, RELICT-2