Many massive extrasolar planets have large orbital eccentricities, in contrast to Jupiter. We cannot observe low-mass planets like the Earth or Mars. The interesting problem is possible existence of stable orbits of terrestrial planets in habitable zones, especially -- quasi-circular orbits. For the regular eccentricity oscillations of Earth-like exoplanet a simple analytical model is derived. In particular, fixed eccentricity points are found. For several known extrasolar systems we found orbits in the habitable zones, with the range of eccentricity oscillations. The orbit's stability is verified using numerical integration. The obtined data complement known results.
This study was supported by the Russian Foundation for Basic Research (grant 05-02-17408), and by the Scientific Program "Russian Universities" (project ur.02.01.301).