杏吧原创

NASA and the European Space Agency say they鈥檝e found a way around a design
blunder which could have ruined data from a probe bound for Saturn鈥檚 moon Titan.
NASA鈥檚 Cassini orbiter was launched in 1997, carrying an ESA probe called
Huygens that will transmit data back to Cassini as it falls through Titan鈥檚
atmosphere in 2004. Only after it was on its way did engineers realise the
Huygens transmitter had not been designed to adjust for the Doppler effect as it
sends signals to the moving Cassini. The flight plan has now been changed so
that Cassini will fly over Titan at a height of 65,000 kilometres rather than
1200 kilometres, decreasing the Doppler shift.