Deferent vs. Epicycle Deferent: A deferent is a large circle that was used by ancient astronomers to explain the motion of planets across the sky. It assumed that all celestial bodies moved around Earth in perfectly circular orbits and so had to account for any irregularities observed from this model. Epicycle: An epicycle is a …
What is the difference between deferent and epicycle? Read More »
Latitude: Latitude is the horizontal lines through the earth. We get the equator with the concept of Latitude. Longitude: Longitude is the verticle lines through the earth. For more explanation: Imagine our world as a three-dimensional ball. Latitudes are imaginary lines that run from west to east, parallel to the equator. The equator is …
The equator is an imaginary line drawn around the middle of the Earth, halfway between the North and South Poles. It is the reference line from which the Earth’s latitude and longitude are measured and divides the planet into two hemispheres. Facts about the Equator: The equator is an arbitrary line that divides the earth …
A constellation is a group of stars that form a recognizable pattern when viewed from Earth. Some constellations have been known since ancient times, while others were only discovered recently. In astrophysics, constellations are used to understand and chart the night sky. They are important for navigation and locating celestial objects such as planets, stars, …
What is a Constellation in Astronomy & Astrophysics? Read More »
A comet is a small celestial body made up of ice, dust, and various gases. They typically have a relatively small solid nucleus, around which a bright and large coma (a cloud of gas and dust) forms as the comet gets closer to the Sun. The coma can be several hundred thousand kilometers across. As …
Great Circle / Geodesic: Any circle that passes through the center of a sphere is called a Great Circle or Geodesic. Small Circle: Any plane intersecting the sphere but not passing through the sphere is called Small Circle.
An equant is a geometric concept used in ancient and medieval astronomy to improve the accuracy of the epicycle and deferent system, which was used to explain the retrograde motion of celestial objects, such as planets. An equant is a point located at a fixed distance from the center of the deferent circle and is …
An epicycle is a geometric concept used in ancient and medieval astronomy to explain the retrograde motion of celestial objects, such as planets. It is a small circle that moves on the circumference of a larger circle, called a deferent, with its own center. The planet is placed at the center of the epicycle and …
The Ptolemaic model of planetary motion is a geocentric model of the solar system that was proposed by Claudius Ptolemy, a Greek astronomer, in the 2nd century AD. In this model, the Earth is stationary at the center of the universe and the celestial objects, such as the sun, moon, and planets, revolve around it …
——————————————————————————————————————————————————————————————————————– Exam Question Answer: Question: What is Retrograde Motion? Answer: Retrograde motion is a phenomenon that occurs when a celestial object appears to move backward in the sky. This is most commonly observed with the planets in the solar system, but it can also be observed with other celestial objects, such as asteroids and comets. …