Heliocentric orbits with periods commensurate with the earth's orbit period

The basic properties of heliocentric orbits of periods commensurate with the earth orbital period are examined. An orbit of the period of 10 months is selected which permits stable Lagrange points of the earth-sun system to be visited and also permits a long-duration (about five months) transit of the spacecraft-earth line in the immediate vicinity of the sun. A double fly-by of these celestial orbits permits reentry to earth.