Luna-28 mission for polar samples return, as the key element of the initial stage of Russian Lunar Program

The most interesting sites for future lunar outposts are thought to be located closely to poles, and South one is found to be more preferable.  But before humans could land there, the sequence of robotic missions should be implemented to study the natural environment at the selected sites, to deliver some supporting systems for ensuring conditions of habitability and also to test the innovated technology for Earth-Moon-Earth round trip.

Therefore, the Russian Lunar Program will be ignited by four robotic missions, which Russian Academy of Science has selected for the initial stage of this Program. Their names Luna-25 -28 were selected taking into account the name of the last Soviet lander Luna-24 of 1976. The objectives of these missions are critically important for accomplishment of the future polar expeditions of humans. The missions will conduct orbital mapping of polar regions with fine spatial resolution, measurements of radiation environment at the selected landing sites, testing of water and space volatiles in the polar regolith, and, in particular – testing presence of complex molecules and pre-biotic molecular complexes, the lunar dust and exosphere, etc. Mobile elements of landing missions will investigate local areas around the landing sites to determine the best spots for the future habitation modules of human missions. In addition, the researches for the basic science will also be accomplished by these missions, such as the experiments for lunar-based astronomy at long wavelengths and at gamma-rays, the experiments for lunar seismology, for monitoring of interplanetary plasma and solar wind, etc.

The talk presents in details the concept of the key mission of the first stage of the Lunar Program, the Luna-28 mission for lunar polar sample return. The mission concept is based on the several basic requirements. The mission should have the return module for direct flight from Moon to Earth. The module should be able to deliver to the Earth a set of samples of polar regolith with the total mass of about 2 kilograms. They should be quarried from different depths of the shallow subsurface from several cm down to 1 meter. Samples should be delivered to the Earth with all volatiles, including water, in the frozen state. Small moonrover “Lunokhod” with mass below 100 kg should be delivered to the Moon by the lander. Before the launch of the return module, the rover could deliver remotely selected stones for return at the nearest vicinity of the lander, after the launch, the rover should conduct scientific studies of the area around the landing site.

The mission of Luna-28 will also be supported by the ground segment for proper curation of delivered samples and for their studies in the leading domestic and international research centers. The complex molecules and organic molecular complexes will be the main objects for these studies.