If the earth was 1km closer to the sun...?

It is not difficult to calculate an answer to your question. The Earth's equilibrium temperature as a function of it's distance from the Sun is: Te^4 = (Rs^2 * Ts^4) / (4 * rs^2)

Where:

Te = temperature of the Earth

Rs = radius of the Sun

rs = average Earth-Sun distance

Ts = surface temperature of the Sun

Using representative values:

Te^4 = (695,000km^2 * 6000K^4) / ( 4 * 150,000,000km^2)

Te = 288.7905815 K

Now with the Earth's orbit 1 km nearer the Sun.

Te^4 = (695,000km^2 * 6000K^4) / ( 4 * 149,999,999km^2)

Te = 288.7905825 K

Subtracting the two temperatures shows that, if the Earth was 1 km closer to the Sun, the planet would be warmer by about 0.000001 K. So, the difference in climate would be negligible.

The calculations are explained clearly at :

http://www.globalchange.umich.edu/globalchange1/cu...

One other thing to consider; to say that the Moon orbits the Earth is an oversimplification. Both actuall orbit about the center of gravity of the system.

What this means is that the Earth wobbles a bit in it's orbit about this center. If I remember right, this center of gravity is about 3000 miles from Earth's center, on the line that connects Earth and Moon.

And (if I'm picturing this correctly) this means that the Earth actuall moves about 6000 miles to and from the Sun in the course of the time from full Moon to full Moon.

I've heard this hogwash about "If the earth were just a half mile closer to the sun..."

And I've wondered how people could swallow such crap.

Do you suppose this could be used as a test to determine just who will believe anything and who will at least think a little bit.

It could be a handy tool for those who want to manipulate others and who want to know who is going to resist.

Pure rubbish.

The earth's orbit is NOT a perfect circle as these people are assuming. It is an ellipse, so at some points in the year the earth is close to the sun, and at some it is further away. I'm not sure how much of a difference it is exactly, but at least a few tens of thousands of kilometres. And the difference cannot be noticed on earth, as it has NO noticeable effect on the seasons at all.

EDIT:

Aphelion 152,097,701 km

Perihelion: 147,098,074 km

There ya go, 5 million kilometres.

Considering at perihelion, the Earth is about 147.5 million km away from the Sun and at the greatest separation, the two are about 152.6 million km apart I wouldn't guess to much of anything.

the Goldilocks zone may extend as much as halfway to Venus , though most believe it smaller than that, but even .75 is another 5 million miles.

earth to sun distance = 150 million kilometers

1 kilometer difference is not significant

From the little that I know about astronomy:

1. The overall global temperature would be between 5-10° hotter.

2. Lakes, rivers, and oceans would dry up somewhat; evaporation.

3. More precipitation overall.

It will be tosted :P