What is the Astronomical Definition of Eccentricity?

Thread starter oscar_lai_hk
Start date Nov 29, 2007

In summary, eccentricity refers to the degree of deviation from a perfect circle in the orbit of a celestial body and is calculated using the formula e = c/a. It is primarily caused by the gravitational pull of other celestial bodies and plays a crucial role in determining a planet's distance from the sun, climate, and stability. Eccentricity can also change over time due to various factors and impact a planet's habitability.

Nov 29, 2007

oscar_lai_hk

What is eccentricity?

Last edited: Nov 29, 2007

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Nov 29, 2007

Janus

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This isn't a homework question is it?

Nov 29, 2007

J77

www.dictionary.com

Nov 29, 2007

CompuChip

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J77 if one would like to find this in a dictionary, it would be nice to spell it correctly

And would read all entries, until one found the one marked "Astronomy" (otherwise, one would get only meanings like weird, erratic, peculiar, ...).

1. What is eccentricity?

Eccentricity refers to the degree of deviation from a perfect circle in the orbit of a celestial body, such as a planet or satellite. It is a measure of how elliptical an orbit is, with a value of 0 representing a perfect circle and a value of 1 representing a highly elongated ellipse.

2. How is eccentricity calculated?

Eccentricity is calculated using the formula e = c/a, where e is the eccentricity, c is the distance between the center and one of the foci of the ellipse, and a is the length of the semi-major axis. This formula is used to determine the shape of an orbit and the distance of a celestial body from its focus point.

3. What causes eccentricity in orbits?

Eccentricity in orbits is primarily caused by the gravitational pull of other celestial bodies. For example, the orbit of a planet may become more eccentric due to the gravitational influence of a nearby massive planet. Additionally, the shape and orientation of an orbit can also be influenced by the initial conditions of its formation.

4. What is the significance of eccentricity in planetary motion?

The eccentricity of a planet's orbit plays a crucial role in determining its distance from the sun and the amount of solar radiation it receives. This, in turn, affects the planet's climate, surface temperature, and potential for life. Additionally, the eccentricity of a planet's orbit can also impact its orbital stability and long-term evolution.

5. Can eccentricity change over time?

Yes, eccentricity can change over time due to various factors such as gravitational interactions with other celestial bodies, tidal forces, and changes in the planet's internal structure. This can lead to significant changes in the orbit and potentially affect the habitability of a planet over time.