ИСТИНА

There are about one million stars within one thousand light years region around the Sun that may have habitable planets and which are interesting from the point of view of the SETI problem. All these stars are acceptable in principle for monitoring with large radio telescopes with aim to catch a radio message from aliens but it is still impossible to monitor all of them due to a lack of special instruments designed for SETI like large antenna arrays. In this situation we propose a special limited list of especially interesting objects to monitor with using of usual large radio telescopes in accompanying mode together with usual astrophysical observations. This list consists of the objects of three types and there are only about three dozen objects in total in the list. The first type of objects is represented by sunlike stars satisfying the following criteria: 1) The spectral type is from F8V to K0V; 2) The estimate of the age of the star is from 4 to 6 billions of years; 3) The distance from the Sun is less than 100 light years; 4) The radial velocity is less than 50 km/sec; 5) If it is known the star to have planets, then the eccentricity of orbits is less than 0.2. The special interest among the sunlike stars satisfying the criteria 1-5 are the near-ecliptic ones, since the Earth is seen from them as a transit planet, therefore the solar system may be a preferable target to send a message for aliens from planets of such stars. The second type of objects is a number of stars that are targets of already sent space messages and at the same time which are sunlike stars satisfying the criteria 1-5. Moreover some slow narrow- band radio signal above background was observed previously from one of the second type object and the result should be verified. The objects of the third class are not stars, but they are globular clusters. We elaborate a number of criteria to select globular clusters but emphasize a high level of metallicity. Many stars in such globular clusters may have earth-like planets. At the same time large number of stars in such a cluster and relatively short distances between stars may promote local interstellar communications between civilizations of the cluster and may produce a kind of a ’supercivilization’ which can install powerful all-directional beacon.