by Natalya KRIVOVA, Dr. Sc. (Biol.), director of the Research Institute of Biology and Biophysics, Tomsk State University, Tomsk, Russia; Kirill TRUKHANOV, Dr. Sc. (Technol.), leading researcher, Institute of Medicobiological Problems, Russian Academy of Sciences, Moscow, Russia Next year, 2011, will see an epic jubilee-fifty years since man's pioneering space flight. On April 12, 1961, Yuri Gagarin circumnavigated the earth aboard the spaceship VOSTOK. Today man sets his sights higher than that-on Mars, in particular. Plans are afoot to build longtime lunar bases. Piloted interplanetary missions are in order. What makes them different from routine orbital flights? PROTECTIVE "SHIELD" OF THE EARTH Tentatively a Martian odyssey is expected to take 1.4 years or so. We might recall that the endurance flight of Valery Polyakov, a medical doctor, on board the MIR orbital station in 1994 and 1995 was almost as long as that-1.2 years.* Compared with circumterrestrial and even lunar flights, an interplanetary mission will be an endurance flight (no cargo ships to supply oxygen, food, water, equipment and the like; there will be a time lag-as much as 40 minutes for a Martian mission-in two-way radio communication sessions. And there will be no geomagnetic field that we are so much used to. Extending far beyond our planet's boundaries, it deflects the larger part of high-energy charged particles coming from the Milky Way galaxy or from the sun, especially during solar flares, and thus shields our bio-sphere. Fortunately the radiant flux (hard electromag-netic radiation quanta-X-ray and high-energy fluxes) reaching the earth from outer space is very small. The geomagnetic field shields the planet's atmosphere, too-otherwise the solar wind would have "blown" it away. Fluxes of galactic cosmic rays are far more intensive in deep space whose interplanetary field is from three to five orders as low as the terrestrial geomagnetic field; this pos ... Читать далее