this post was submitted on 06 Mar 2025
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They were only able to receive signals from the bare minimum to achieve a solution (4 GPS and 1 Galileo). Their achieved accuracy was +/- 1.5km and +/- 2m/s. That is good enough in astronomic scales to get you to a planet, but it isn't going to help failed landings or autonomous landings.
I don't think there was any new tech involved, just a receiver put on a moon lander to see if it could detect signals. And this won't really do anything for Mars for two reasons: 1) the signal strength would be too small for any reasonable antenna to detect GPS L1/L5 at Mars distances, and 2) the distance would make the geometry be unusable to trilaterate a solution... think about a triangle where two lengths are 100 million miles and the third length is 100 miles. That is a completely worthless geometry for trilateration of a position solution. Even if we could somehow detect a GPS signal at Mars, best case is we get atomic clock time.
Which is an improvement in of itself. That improves flying craft navigation to and from the moon into something significantly easier to automate and coordinate between multiple ships, more than ballistic dead reckoning.
is it really such a huge deal ? Afaik "ballistic dead rekoning" is really, really accurate and isnt difficult to automate (it's mostly math after all)
For longer missions it helps to be able to re-calibrate, as with dead-reckoning, the errors cumulate