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Name: gary
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 1999 - 2000

In interstellar space - how does a spacecraft measure it's velocity in real time? I can understand the use of 3 gyroscopes to measure changes in direction or the use of celestial navigation for changes in direction - but as for velocity - no clue.

The only thing I can think of is to measure the doppler shift of spectral lines in starlight. You'd need a pretty sensitive detector to get good real-time response, though, and you'd also need reference shifts and star velocities for accuracy.

Tim Mooney

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