4 ms·

0.0 eccentricity means that it has no seasonal variation?

mitthrowaway2 3y ago
It means its orbit is a circle. Seasonal variation is due to the tilt of the planet's axis of rotation relative to its orbit, not orbital eccentricity.
- rglullis 3y ago
  I know what causes seasonal variations, but for some reason I thought 0.0 eccentricity meant no tilt. Thanks
- wkat4242 3y ago
  Well on our planet that's the case. Another planet might well have seasons due to orbital eccentricity. Though it would have to be pretty serious eccentricity I think. If they would have no tilt then the seasons would be the same all over the planet unlike ours where they're opposite in each hemisphere.
MadnessASAP 3y ago
It means the orbit is perfectly circular. Earth's seasons are driven almost exclusively by our axial tilt*, not our orbital eccentricity. Our eccentricity also being 0.0(167). * Astrometeorologists feel free to correct me on this.
- fbdab103 3y ago
  Wikipedia says this The relative increase in solar irradiation at closest approach to the Sun (perihelion) compared to the irradiation at the furthest distance (aphelion) is slightly larger than four times the eccentricity. For Earth's current orbital eccentricity, incoming solar radiation varies by about 6.8%, while the distance from the Sun currently varies by only 3.4% (5.1 million km or 3.2 million mi or 0.034 au).[9] Perihelion presently occurs around 3 January, while aphelion is around 4 July. When the orbit is at its most eccentric, the amount of solar radiation at perihelion will be about 23% more than at aphelion. However, the Earth's eccentricity is so small (at least at present) that the variation in solar irradiation is a minor factor in seasonal climate variation, compared to axial tilt and even compared to the relative ease of heating the larger land masses of the northern hemisphere.[10] https://en.wikipedia.org/wiki/Milankovitch_cycles https://en.wikipedia.org/wiki/Milankovitch_cycles

It means its orbit is a circle. Seasonal variation is due to the tilt of the planet's axis of rotation relative to its orbit, not orbital eccentricity.

rglullis 3y ago
I know what causes seasonal variations, but for some reason I thought 0.0 eccentricity meant no tilt. Thanks
wkat4242 3y ago
Well on our planet that's the case. Another planet might well have seasons due to orbital eccentricity. Though it would have to be pretty serious eccentricity I think. If they would have no tilt then the seasons would be the same all over the planet unlike ours where they're opposite in each hemisphere.

MadnessASAP 3y ago

It means the orbit is perfectly circular. Earth's seasons are driven almost exclusively by our axial tilt*, not our orbital eccentricity. Our eccentricity also being 0.0(167). * Astrometeorologists feel free to correct me on this.

fbdab103 3y ago
Wikipedia says this The relative increase in solar irradiation at closest approach to the Sun (perihelion) compared to the irradiation at the furthest distance (aphelion) is slightly larger than four times the eccentricity. For Earth's current orbital eccentricity, incoming solar radiation varies by about 6.8%, while the distance from the Sun currently varies by only 3.4% (5.1 million km or 3.2 million mi or 0.034 au).[9] Perihelion presently occurs around 3 January, while aphelion is around 4 July. When the orbit is at its most eccentric, the amount of solar radiation at perihelion will be about 23% more than at aphelion. However, the Earth's eccentricity is so small (at least at present) that the variation in solar irradiation is a minor factor in seasonal climate variation, compared to axial tilt and even compared to the relative ease of heating the larger land masses of the northern hemisphere.[10] https://en.wikipedia.org/wiki/Milankovitch_cycles https://en.wikipedia.org/wiki/Milankovitch_cycles