Asimov in action

From Second Foundation (1948 to 1953):

Bail Channis sat at the control panel of the Lens and felt again the involuntary surge of near-worship at the contemplation of it. He was not a Foundation man and the interplay of forces at the twist of a knob or the breaking of a contact was not second nature to him.

The answer was of course spectographic analysis. For many centuries the main object of interstellar engineering was the analysis of the “light signature” of more and more stars in greater and greater detail. With this, and the growing precision of the “hop” itself, standard routes of travel through the Galaxy were adopted and interstellar travel became less of an art and more of a science

* The current best guess is that there are 150 – 250 billion stars in the Galaxy, maybe they didn’t assume that seventy years ago? Elsewhere in the books is an explanation of a heads-up display, you just keep adjusting the virtual galaxy until it lines up against what you can actually see and hey presto, the computer tells you where you are.

From Sky News:

Prof Jorgensen had designed the four instruments that Juno used to track stars as part of its magnetometer investigation.

NASA explained that these onboard cameras took photographs of the sky every quarter of a second to determine Juno’s orientation in space by recognising the patterns of the stars – an engineering task which was “essential” to the magnetometer’s accuracy.

Which is the same general principle. I’m surprised that triangulation works on such a small scale (well within the solar system) because the parallax differences must be minuscule, but they seem to be able to make it work.