Download or read book The Difficult Road to Mars: a Brief History of Mars Exploration in the Soviet Union written by V. G. Perminov and published by CreateSpace. This book was released on 2012-07-12 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mars is the planet in our solar system thought to be most like Earth. The Martian period rotation is 24 hours, 37 minutes, and its angle tilt with respect to its orbital plane is about 64.8, compared to 66.5 of Earth. As a result, seasonal changes occur similarly to earth. This book is about learning more about Mars and eventually getting there.