No modern astronomer made a more profound contribution to our understanding of the cosmos than did Edwin Hubble, who first conclusively demonstrated that the universe is expanding. Basing his theory on the observation of the change in distanct galaxies, called red shift, Hubble showed that this is a Doppler effect, or alteration in the wavelength of light, resulting from the rapid motion of celestial objects away from Earth. In 1935, Hubble described his principal observations and conclusions in the Silliman lectures at Yale University. These lectures were published the following year as "The Realm of the Nebulae," which quickly became a classic work.

Book Information
ISBN 9780300025002
Author Edwin Hubble
Format Paperback
Page Count 260
Imprint Yale University Press
Publisher Yale University Press
Weight(grams) 335g
Dimensions(mm) 216mm * 140mm * 15mm