Astronomy/astronomy

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Expert: - 6/15/2004


Question
Why does the earth rotate counterclockwise around the sun?


Answer
Hello.

The direction of Earth's *revolution* about the Sun (not rotation, which is what we mean by the Earth turning on its own axis) was probably set at the time of the early Solar Nebula.

As you may know, the solar system began as a vast cloud from which the Sun condensed and began nuclear burning as a star. In the early stages, material from the primitive Sun spun off to form the planets, and angular momentum was transferred from the rotating Sun to provide the inital motions to the planets.

This physical process resulted in the Sun slowing in its rotation, even as the planets sped up faster and faster in their respective orbital motions. ("Conservation of Angular Momentum")

It seems reasonable to suppose, therefore, that the direction of this angular momentum transfer was such that it led to a counterclockwise (as opposed to clockwise) direction of the early -primitive planetary masses about the Sun.

Please note that the preceding is intended to show *HOW* the Earth acquired its counter-clockwise motion about the Sun.

In Science, alas, we refrain from 'Why?' questions, preferring to leave those to the theologians.

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Philip Stahl

Expertise

I have forty years of experience in Astronomy, specifically solar and space physics. My specialties include the physics of solar flares, sunspots, including their effects on Earth and statistics as applied to astronomical investigations.

Experience

Astronomy: more than forty years experience starting with construction of my own simple telescopes. Worked at university observatory in college, doing astrographic measurements. M.Phil. degree in Physics/Solar Physics and more than ten years as researcher.

Organizations
American Astronomical Society (Solar Physics and Dynamical Astronomy divisions), American Mathematical Society, American Geophysical Union

Publications
Solar Physics (journal), The Journal of the Royal Astronomical Society of Canada, The Proceedings of the Meudon Solar Flare Workshop (1986), The Proceedings of the Caribbean Physics Conference (1985). Books: 'Selected Analyses in Solar Flare Plasma Dynamics', 'Physics Notes for Advanced Level'.

Education/Credentials
B.A. Astronomy, M. Phil. Physics

Awards and Honors
American Astronomical Society Studentship Award (1984), Barbados Government Award for Solar Research

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