Is the distance between sun and earth a constant?

Question

Is the distance between sun and earth a constant?

Answer 1

No, it changes from 149 million km to 151 million kms.

Answer 2

NO.SINCE THE  EARTH ROTATES IN AN ELLIPTICAL ORBIT,THE DISTANCE WILL VARY AT VARIOUS POINTS.

Answer 3

the distance is not constant..bcoz earth revolves around the sun in elliptical path.it is closest to sun in winters or in december or january and furtherest in june or july

Answer 4

no, the earth's orbit (as all other planetary bodies) is an ellipse, not a circle.

haven't you ever heard people talk about how the earth is closer to the sun during the northern hemisphere's winter?

Answer 5

no because the earth orbits around the sun in an elliptical orbit. if it was a cycle than yes but in the ellipse the earth has 2 point which are nearest to the sun and 2 which are more distant to the sun

Answer 6

It varies by 3% throughout the year because it's very slightly egg-shaped.

Answer 7

No--the earth orbits in an elliptical shape, not a circle

Answer 8

Not quite.  The orbit is elliptical, with a minimum distance of 91.5 and a maximum of 94.5 million miles to the sun.  Closest approach to the sun is about January 4 -- which causes northern hemisphere winters to be a bit warmer than they would be otherwise.

Answer 9

It is, by far, not constant. Primarily the orbit is elliptical with current eccentricity of 0.01671, so the distance keeps changing throughout the year. Furthermore, the eccentricity  roughly completes a cycle in about 100,000 years (the Milankovic cycle), having values oscillating between 0.10 and 0.25. Also the semi-major axis keeps varying, currently it is reducing at a rate of about 7 metres per year.

Answer 10

No its not constant

Answer 11

No. The earth's orbit is not a perfect cricle; it's an ellipse.  The average distance is approx 93 million miles or 1 AU [astronomical unit].

From the source below:

Changes in orbital eccentricity affect the Earth-sun distance. Currently, a difference of only 3 percent (5 million kilometers) exists between closest approach (perihelion), which occurs on or about January 3, and furthest departure (aphelion), which occurs on or about July 4. This difference in distance amounts to about a 6 percent increase in incoming solar radiation (insolation) from July to January. The shape of the Earth�s orbit changes from being elliptical (high eccentricity) to being nearly circular (low eccentricity) in a cycle that takes between 90,000 and 100,000 years. When the orbit is highly elliptical, the amount of insolation received at perihelion would be on the order of 20 to 30 percent greater than at aphelion, resulting in a substantially different climate from what we experience today.