The orbit of planets around the Sun is described by giving its semi-major axis (a) and its eccentricity (e). An eccentricity of zero corresponds to a circular orbit and eccentricity greater than zero and less than one corresponds to an elliptical orbit. The value of eccentricity of the Earth's orbit is :

Question

Prepp Team · Accepted Answer

The question asks for the eccentricity of Earth's orbit. Let's break down the concept of eccentricity and apply it to this problem:

Understanding Eccentricity:

Definition: Eccentricity (e) measures how much an orbit deviates from being circular.
Eccentricity Values:
- e = 0 corresponds to a perfect circle.
- 0 < e < 1 indicates an elliptical orbit. The closer to 0, the more circular the ellipse.

Earth's Orbital Eccentricity:

The Earth's orbit is known to be nearly circular. Let's evaluate the given options based on their numerical value:

Option 1: 0.0017 - This value is too low, even though it's closer to a circular orbit, it is less commonly referenced as Earth's orbital eccentricity.
Option 2: 0.1670 - This value is too high for Earth's orbit and would indicate a more elongated ellipse.
Option 3: 0.0167 - This value is commonly known and accepted as the eccentricity of Earth's orbit.
Option 4: 0.6710 - This value suggests a highly elongated orbit, which is incorrect for Earth.