The giant star Betelgeuse has an angular diameter as observed from Earth of about 0.05 arc seconds. If the star is 600 light years away from us, what is the physical diameter of the star in km? Compare this to the sun’s diameter of 1.4x10^6 km. The sun is about 1.6 x 10^(-5) light years from Earth.

The giant star Betelgeuse has an angular diameter as observed from Earth of about 0.05 arc seconds. If the star is 600 light years away from us, what is the physical diameter of the star in km? Compare this to the sun’s diameter of 1.4x10^6 km. The sun is about 1.6 x 10^(-5) light years from Earth.

Astronomy

1st Edition

ISBN:9781938168284

Author:Andrew Fraknoi; David Morrison; Sidney C. Wolff

Publisher:Andrew Fraknoi; David Morrison; Sidney C. Wolff

Chapter17: Analyzing Starlight

Section: Chapter Questions

Problem 34E: As seen from Earth, the Sun has an apparent magnitude of about 26.7 . What is the apparent magnitude...

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