Mathematical SETI

Part of the series Springer Praxis Books pp 349-360


FOCAL mission to 1,000AU as an interstellar precursor

  • Claudio MacconeAffiliated withInternational Academy of Astronautics and Istituto Nazionale di Astrofisica Email author 

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The nearest stellar system, the Alpha Centauri three-star system, is located about 4.40 light-years away. This amounts to 278,261 AU. However, the focus of the gravitational lens of the Sun is found at only 550 AU—or, more generally, at only about 1,000AU—which is then 278 times closer than our nearest interstellar target. In other words, assuming equal engineering problems, the trip to the Sun’s focus takes 278 times less than the time to the nearest stellar target. This makes the Sun focus a reasonable target for our probes to reach within this century.