3 ms·

Parallax. (And not stars, but other solar system objects.)

• lisper 8y ago
  You'd think, but no, that's not actually how it's done. See e.g.: http://dnc.tamu.edu/drjunkins/yearwise/2000/conference/AIAA_GNC_2000_Orbit_Navigation.pdf http://dnc.tamu.edu/drjunkins/yearwise/2000/conference/AIAA_... https://core.ac.uk/download/pdf/9069467.pdf https://core.ac.uk/download/pdf/9069467.pdf for some state-of-the-art research on this topic.
  • garmaine 8y ago
    Actually, in the case of New Horizons, it is. Mission navigators use LORRI images of known objects relative to the background stars to calibrate their position.
    • lisper 8y ago
      OK, I stand corrected.