View Full Version : Orbit of earth and mars

2006-Jan-01, 09:43 PM
Why is the variation of the difference in the orbit of mars from closest and most distance to the sun much greater than earths difference from closest to most far away from the sun? And why is plutos distance to the sun so extreme different ,and earths orbit so equable,while earth has seasons. And why has venus (no) seasons,while the orbit of venus is also irregular,and venus distance to the sun is also different. Can you explain this? Thanks,Denis. And whats earths distance to the sun at this moment,when is earth closest and most distant to the sun?

2006-Jan-02, 01:24 AM
The earths seasons are actually caused because the earths axis is tilted, therefore making sunlight spread across larger areas in some areas. This causes Winter and Summer to happen every year.

umop ap!sdn
2006-Jan-02, 01:57 AM
Venus' equator has very little tilt to its orbit, contrasted to Mars which has slightly more equatorial tilt than Earth does. Earth reaches aphelion around July 2 of every year, IIRc, so at the moment it's pretty close to perihelion. :)

2006-Jan-02, 04:52 AM
Mars is closer to Jupiter. Pertabutions from Jupiter are mainly responsible for the eccentricity of Mars and Earth.

But the eccentricities (roundness of orbits) of both Earth and Mars fluxuate over periods of millions of years from near-circles to maximum. Sometimes Mars' orbit is more circular than Earth's.

Presently, Earth is 147 million km from the Sun as it is near perihelion. In about 6 months, it will be 152 million km from the Sun at aphelion.

Venus' orbit is quite round. It presently fluxuates between 107 million and 109 million km.