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Comment by araes

10 days ago

Not surprisingly, this is actually one of the main issues with space travel and sending probes almost anywhere. Get slightly misasligned and you have take sightings on star patterns to try to somehow figure out where you are and what your orientation is. Voyager 1 and 2, Pioneer 10 and 11, and New Horizons all had / have variations on those systems.

Spacecraft Attitude Determination, https://en.wikipedia.org/wiki/Spacecraft_attitude_determinat...

Star Tracker, https://en.wikipedia.org/wiki/Star_tracker

I've had colleagues working on a pulsar navigation system to improve on star sightings.

The idea is to look for the X-ray signals coming from pulsars and then use the frequency of the pulse to identify the pulsar and then match that to a known map to figure out where you are. It's pretty cool and theoretically can work even for interstellar spaceflight.

https://en.wikipedia.org/wiki/Pulsar-based_navigation

Not to mention the astroinertial guidance system on ICBM nuclear missiles.

To wit, there are 12 Ohio class submarines each with 20 trident missiles each carrying 12 maneuverable nuclear warheads (475 kilotons each).

The missiles are launched under water, reach Mach 18 in 2 minutes, and don’t need GPS — they use the stars to deliver their payload.

I saw a test missile launch once before. It still terrifies me.

https://en.wikipedia.org/wiki/Ohio-class_submarine