Tens, hundreds or thousands? - Sagan's message for Mars
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On the 25th of May 2008 the Phoenix safely landed upon Mars. It carried with it a DVD made of silica glass, designed to last the tens, hundreds or thousands of years it may take for humans to visit Mars and to rediscover it. It contained messages and artworks chosen for future visitors to discover when humans eventually travel to the planet. Among them was a message from the late Carl Sagan.