Quote:
Originally Posted by multiweb
What margin of error do we have from our current excentricity before we run into serious problems with our surface temperature. Is this orbit shape something that can potentially get big enough? Has it in the distant past? I guess how thick is the 'comfort' zone from the sun?
|
The habitable zone around the Sun is more than large enough to encompass any conceivable deviation in the Earth's orbit, apart from catastrophic ones. However, a substantial change in the eccentricity of the orbit of the planet would cause problems. At present, the seasonal changes in solar insolation averages out to around 6%. If it were to become substantially larger or smaller, there would be climate consequences for the planet.
Because of chaotic interactions with the other planets over long periods of time, it's impossible to accurately predict what the orbit of the planet will be. So, in a billion years time, the orbit of our planet could be substantially different to what it is now. However, it's believed that the orbits of the major planets will remain stable over very long periods of time...on the order of many billions of years.