The astrolabe is primarily used to measure the altitude of celestial bodies above the horizon.

The astrolabe was invented by the Greek astronomer Hipparchus in the 2nd century BC.

The main component of an astrolabe is a graduated circle, which is used to measure the altitude of celestial bodies.

The pointer on an astrolabe is used to measure the altitude of celestial bodies above the horizon.

The sighting tube on an astrolabe is used to determine the direction of Mecca, which is important for Muslims during prayer.

The plumb line on an astrolabe is used to determine the direction of Mecca, which is important for Muslims during prayer.

The astrolabe was used in Indian astronomy for a variety of purposes, including measuring the altitude of celestial bodies, calculating the time of day, and determining the direction of Mecca.

The astrolabe was first introduced in India in the 12th century AD by Arab traders.

Bhaskara II was the first Indian astronomer to use the astrolabe.

The primary use of the astrolabe in Indian astronomy was measuring the altitude of celestial bodies.

The astrolabe contributed to the development of Indian astronomy in several ways, including enabling astronomers to make more accurate observations, calculate the positions of celestial bodies, and predict the occurrence of celestial events.

The astrolabe has several limitations, including that it can only be used at night, it is not accurate enough for precise measurements, and it is difficult to use.

The astrolabe has several modern applications, including navigation, surveying, and astronomy.

There are several challenges in using the astrolabe, including that it is difficult to learn how to use, it is not very accurate, and it is not portable.

The astrolabe is not easy to use, it is not very accurate, and it is not portable.