Sailors used astrolabes and sextants to measure what?

Here is the question :

SAILORS USED ASTROLABES AND SEXTANTS TO MEASURE WHAT?

Here is the option for the question :

• Ocean depth
• Temperature
• Celestial objects
• Weather

The Answer:

And, the answer for the the question is :

Explanation:

[STC0019039]. While both astrolabes and sextants are used by sailors to navigate by the stars, their purposes are slightly different. Astrolabes were multi-purpose instruments used by both Greek and Arab mariners to measure the altitude of celestial objects, determine latitude and longitude, and survey distance, among other things. A sextant, while similar, estimated the distance between two celestial objects for navigation purposes. Long before satellite navigation, both were essential equipment on the high seas.