|MadSci Network: Astronomy|
Jessica, I assume you mean what would happen if Earth's axis was perpendicular to the ecliptic--the plane of the Earth's orbit. First of all, there would be no real seasons as we know them. Seasonal variation in temperature is caused by the varying Sun angle as the tilted axis of the Earth orbits the Sun. If there was no axial tilt, the sun angle at a given time of day would remain the same all year. Sunrise and sunset would also happen at the same time all year (with minor variations due to the ellipticity of Earth's orbit). It's interesting also to contemplate what would be different about our weather. Since the higher latitudes would get the same amount of sun all year, they would probably tend to stabilize at temperatures similar to fall and spring in a given region. But without the seasonal changes, weather cycles might be very different from the way we know them. It's a difficult thing to analyze completely. Keep asking great questions like this one and you'll never stop learning new things. -Adams Douglas Senior Developer Infonex, Inc.
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