- #1

roscoe67

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- TL;DR Summary
- celestial navigation question: can one predict the path of the sun over a day by single observation along the transit?

Hi. I have this idea that might be useful for celestial navigation. If you were on a random place on the Earth, and you had a way of measuring the altitude of the sun above the horizon, at a precise moment, could you then predict the complete path, such that you could determine the altitude at solar noon (the highest position of the sun in that day), and thus calculate latitude (adjusting for solar declination)?

In other words, let's say you set your sextant to 25 degrees above the horizon. If you knew when the sun crossed that altitude (let's say to the second), could you then calculate what would be the sun's highest point?

One thing you

Let's also assume you know the date.

Is this possible to do?

Thanks!

the idea:

In other words, let's say you set your sextant to 25 degrees above the horizon. If you knew when the sun crossed that altitude (let's say to the second), could you then calculate what would be the sun's highest point?

One thing you

__would__have in this equation would be longitude - you could use the fixed sextant to find the time that the sun passes 25 degrees on it way up__and__down - averaging the time crossing 25 degrees ascending and descending would give you solar noon, and hence (adjusting for equation of time), longitude.Let's also assume you know the date.

Is this possible to do?

Thanks!

the idea: