0
Astral navigation, no matter what instrument was used, involves measuring angles of the sun or stars with respect to a reference line.
For seafarers, the astrolabe -- specifically, the mariner's astrolabe -- is an ancient tool for navigating by the sun or stars. Unlike the common astrolable, the mariner's version was designed to be used somewhat more easily on rough seas or high winds. It was not particularly accurate, but it served the purpose.
The simple quadrant operated on a different and somewhat more advanced principle than the astrolabe. The name referred to the device's ability to measure up to 90 degrees, a quarter of a circle. It used a plumb line (a weighted string or wire) as the vertical reference and measured the altitude of the celestial body with respect to the line.
The sextant was designed to measure the angle between the sun or a star and an external reference such as the horizon. It was far more accurate than measuring the angle between the body and the instrument itself, which is how the astrolabe and the quadrant worked. The name refers to the scale's length being 1/6th of a circle. The octant is a variation of the sextant with a scale that is 1/8th of a circle.
All of them assume that the navigator has a deep knowledge of the astronomical references such as sun's position or the locations of specific stars at every day of the year, or has a detailed book of tables. The A competent navigator can determine latitude easily, and with an accurate clock can also determine longitude.
Although GPS has largely replaced the sextant as a necessary instrument, the sextant is still widely used for nautical navigation, if only by sea-loving diehards and purists, or as backups if the batteries in the Garmin die. They have become quite complex, but they still use ancient principles.
For the sextant user, the US Naval Observatory issues "The Nautical Almanac" that gives all the data needed for accurate navigation by the sun or stars.
Wikipedia has a series of articles on the various devices. Google the names and look for the Wiki pages.
What else can I help you with?
What instruments are used to determine the alititude of the north star?
celestial navigation
Who developed celestial navigation?
Celestial navigation has been used for centuries, with its development attributed to various ancient civilizations. The Polynesians, Greeks, and Arabs all made significant contributions to the techniques and tools used in celestial navigation. Notably, the use of the astrolabe and the sextant were key advancements in the practice, with the latter being refined in the 16th century by navigators like John Harrison. The combination of knowledge from these cultures laid the foundation for modern celestial navigation.
What is the significance of the Polaris name in relation to celestial navigation?
The name Polaris is significant in celestial navigation because it is the North Star, which remains nearly fixed in the sky and can be used to determine direction when navigating.
Who invented celestial navigation?
Celestial navigation has been used for centuries by various civilizations, but its modern form can be attributed to early astronomers like Hipparchus and Ptolemy. They developed mathematical models to predict the positions of celestial bodies, which sailors later used to navigate the seas.
What is greenwich celestial?
Greenwich Celestial refers to the Prime Meridian as it crosses the celestial sphere above Greenwich, UK. It serves as the global reference point to measure longitude and is used in celestial navigation and astronomy.
What are the bodies concerning celestial navigation?
nearly all heavenly bodies that can observed by the naked eye can be used for navigation.... assuming you can identify the body of course!
What is an almucantar?
An almucantar is a small circle on the celestial sphere, parallel to the horizon, used in astronomy and navigation to show the altitude of a star or some other heavenly body.
Instrument for taking altitude of sun or stars?
The sextant is used in celestial navigation.
What was the use of the celestial navigation?
Before proper maps, gps and similar, it was used to find the way around the globe.
What tool is used for ship navigation using the stars?
A sextant is a tool used for ship navigation by measuring the angles between celestial objects, typically the stars, and the horizon. This information can then be used to calculate the ship's position on a nautical chart.
what did the captain on the mayflower use to navigate his ship?
The captain of the Mayflower, Christopher Jones, primarily used traditional navigation methods such as dead reckoning and celestial navigation. Dead reckoning involved estimating the ship's position based on speed, time, and direction traveled. For celestial navigation, he would have used instruments like the astrolabe or quadrant to determine the ship's latitude by observing the sun and stars. Maps and charts of the time also aided in their navigation across the Atlantic.
What celestial objects did Hernando courtes use?
Hernando Cortés, the Spanish conquistador, used celestial navigation techniques that involved the sun, stars, and the moon to guide his expeditions. Specifically, he likely utilized the North Star (Polaris) for latitude and the sun's position for determining direction during the day. These celestial objects were crucial for navigation, especially in the uncharted waters of the New World.
