ASTROBIOLOGY VS. SETI: EXPLORING THE PAST VS. EXPLORING THE FUTURE

摘要

The current flourishing of Astrobiological studies is an achievement of contemporary science. In fact, Astrobiology aims at unifying into a single body of knowledge many scattered contributions that previously were investigated in rather separated branches of science. This merging of previously scattered contributions into a new single field can only be of help to enable further scientific progress. Still Astrobiology seems to have one basic limitation: it is concerned only with the scientific understanding of past events. Even if the study of the past is made with an eye to the future, yet Astrobiology can hardly call itself a "science of the future". Although some narrow-minded scientists might claim that "a science of the future does not exist", in this paper, we would like to contend that humankind's future might already have been some alien civilization's past! It is thus necessary for humankind to know whether alien civilizations (necessarily more advanced than us) live or not in the Galaxy. This is just the goal of SETI, the Search for ExtraTerrestrial Intelligence. SETI searches started up in 1960 even before the term "Astrobiology" was invented. Thus, SETI is a "bolder" science than Astrobiology itself, and SETI has profound implications on philosophical, religious and political beliefs. This accounts for the total ban on NASA SETI searches imposed by the political lobbies of the US Congress as early as October 1993. Actually SETI scientists so far failed to prove that other ExtraTerrestrial Civilizations exist in the Galaxy (or elsewhere). Yet, these scientists also made such terrific advances in computer technologies for SETI that a short scientific outline of the SETI technological achievements is given in this paper for the benefit of all the "pure" Astrobiologists, probably unaware of them.