A year and a half before the arrival of the expedition, which left from the region of Alpha in Aquarius, a second exploration fleet, acting in the name of the Institute, placed an automatic satellite — Luna 247 — into orbit around Solaris. This satellite, after three successive reconstructions at roughly ten-year intervals, is still functioning today. The data it supplied confirmed beyond doubt the findings of the Ottenskjöld expedition concerning the active character of the ocean’s movements.

One of Shannahan’s ships remained in orbit, while the two others, after some preliminary attempts, landed in the southern hemisphere, in a rocky area about 600 miles square. The work of the expedition lasted eighteen months and was carried out under favorable conditions, apart from an unfortunate accident brought about by the malfunction of some apparatus. In the meantime, the scientists had split into two opposing camps; the bone of contention was the ocean. On the basis of the analyses, it had been accepted that the ocean was an organic formation (at that time, no one had yet dared to call it living). But, while the biologists considered it as a primitive formation — a sort of gigantic entity, a fluid cell, unique and monstrous (which they called ‘prebiological’), surrounding the globe with a colloidal envelope several miles thick in places — the astronomers and physicists asserted that it must be an organic structure, extraordinarily evolved. According to them, the ocean possibly exceeded terrestrial organic structures in complexity, since it was capable of exerting an active influence on the planet’s orbital path. Certainly, no other factor could be found that might explain the behavior of Solaris; moreover, the planeto-physicists had established a relationship between certain processes of the plasmic ocean and the local measurements of gravitational pull, which altered according to the ‘matter transformations’ of the ocean.