Courses for Kids
Free study material
Offline Centres
Store Icon

Orbit Astronomy

Last updated date: 28th May 2024
Total views: 358.5k
Views today: 10.58k
hightlight icon
highlight icon
highlight icon
share icon
copy icon

Introduction to Orbit Astronomy

In astronomy, Orbit is recognized as a different term. Orbit is a term that is associated with the path of a rotating body about an attractive center of mass.

For example, the revolution of a planet around the Sun, or the revolution of a satellite around the earth or other planets. Johannes Kepler and Isaac Newton were the first to discover the laws on orbits. 

They had discovered the basic physical laws of physics in the 17th century. In this article, you will learn about earth orbit and many other related facts about the orbit.

Planetary Orbits

Albert Einstein has also contributed to this law. In the 20th century, he put forward the general theory of relativity. This theory has sufficient information that can give a more exact description.

The elliptical shape is the path that the planets are revolving. Each orbit of a planet has no relation with another planet or satellite.  They won’t affect each other by some sort of attraction or any other magnetic forces. 

Some planets do have orbits which are almost circles. But in general, the orbits of the planets are always in the elliptical trajectory path. Most of them are much elongated. Several bodies are there in space who may follow the paths of either parabolic or hyperbolic. These types of paths are some sort of open-ended curves. 

In our solar system, the orbit of a planet is curving around the sun. The approach of the orbit elliptical when it stands at a very great distance. This promotes the curving of the trajectory path of the planet that revolves around the Sun. The curve also retreats again when it is not closed to the sun. It forms an open curve. 

[Image will be Uploaded Soon]

We need to determine the elements of the orbit of a body at three random positions. By doing so, we can easily find out the trajectory path of the satellite or the planet. This is the only way to measure the behaviour of the Orbit Astronomy. 

Even Observations are the most interesting facts to take. You should measure the considerable arc of the orbit for making the process appropriate. 

Also, you need to go for upcoming measurements. All of these processes are necessary to describe the effects of minor disturbing forces. 

The examples of disturbing forces that can alter the orbits are:

  • Planetary attractions 

  • Irregularities of mass at the center of the orbit (conducted within the body) 

  • Presence of some artificial satellites 

  • Atmospheric drag

Stationary Orbit

The ‘stationary orbit’ is a term that refers to an orbit. This is an orbit that exists around a planet or moon in celestial mechanics

The objective of the stationary orbit is the revolution of an orbiting satellite or a spacecraft that revolves at its axis (on the same spot) of the surface. You will observe that the satellite is stationary as the view from the ground will give you an exact look.

You may think that the satellite is hovering above the surface and remains at the same spot with time (day after day).

However, it is in rotation. You just can’t observe the behaviour from the surface below. This behaviour can be attained by the satellite when they reach a particular altitude.  At that point, the matching of the orbital speed and the rotation of the satellite occurs. It happens in an equatorial orbit.

Due to the gradual decrease of the speed, an extra boost is necessary to provide the support for the gain of the speed of the rotating satellite. It can restore the speed to a matching one with the help of a retro-rocket. It is also useful for slowing the speed when too fast.

Clarke Belt is the region of the space where we name it for the stationary-orbit region. The name is kept after writer Arthur C. Clarke. He was a British science fiction writer and publisher and had published some concepts in the Wireless World magazine in 1945. Fixed orbit is another term that is useful for the stationary orbit.

Orbit System

[Image will be Uploaded Soon]

Some common points are necessary to understand the orbit system:

  • Gravitational force always pulls an object into a curved path. This is due to the attempt of flying away from the straight path.

  • When a massive body tries to pull another small one, the small body goes towards that massive one. Somehow, the small body hasn’t enough tangential velocity to go on. It will fall into the body.  However, it can continue to follow the curled (bent) trajectory.

This happens due to that massive body. This is the process where we call the body is in the orbiting path.


To provide the right idea for an orbit around a planet, the use of Newton's cannonball model is suitable.  In this experiment, a cannon is placed on top of a tall mountain. It can have the liberty to fire the cannonball in a horizontal path. The muzzle speed can also be chosen. The experiment can show you the ideal concepts of escape velocity and the trajectory path of the object.

FAQs on Orbit Astronomy

Q1. Mention the Keplerian Elements.

Ans: These are the points that present in the Keplerian elements:

  • Right Ascension of Ascending Node

  • Eccentricity

  • Epoch Time

  • Orbital Inclination

  • Mean Motion

  • Argument of Perigee

  • Mean Anomaly

Q2. Situate the Three Orbital Parameters of the Earth.

Ans: Here are the following points associated with orbital parameters of the earth:

1) eccentricity 

(2) axial tilt (or obliquity)

(3) time of perihelion (or precession)

These three parameters explain that the earth is revolving around the sun. Each parameter is useful for the study of the orbit and trajectory motion of the planet earth.

Q3. How Do You Write about Eccentricity?

Ans: The amount of dissimilarity of the orbit of the Earth around the Sun from the rounded path into another extra elliptical is known as eccentricity. Two main periodicities are there in eccentricity. The first one has a cycle of an average of around 100,000 years and the second one has a longer cycle, i.e. around 4,13,000 years.

Q4. What Does Prevent the Tilt of the Earth?

Ans: Moon is responsible for avoiding the tilt of the earth. The gravitational force generated from the moon does not allow the axis of the earth to tilt. This behaviour also protects us from many natural calamities and other problems from the sun.

Students Also Read