... Each day we feature a different image or photograph of our fascinating universe, along with a brief explanation written by a professional astronomer. December 6, 1995 . 24 Hours from Jupiter . Credit: NASA , R. Beebe, NMSU . Explanation: NASA's robot spacecraft Galileo began its long voyage to Jupiter more than six years and 2.3 billion miles ago. About 24 hours from now it will reach its destination. ... Tomorrow's picture: Galileo's Jupiter Probe . ... About APOD | ...