Astronomy/Physcial Science

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Expert: - 7/10/2008


Question
Why do astronauts in orbit around earth see a black sky with stars that do not twinkle but see a blue sky?

Answer
Hello,

Blue sky is caused by sunlight selectively scattered by the atmosphere, and in space there is no atmosphere. Thus, the sky will appear black.

Twinkling of stars is caused by starlight passing through the atmosphere and being subject to turbulence, distortion on the way.In space, again, since there is no atmosphere, starlight will not suffer distortions. So ...no twinkling of stars.

Hope this helps, as your question was phrased in a rather confusing way.

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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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