This section is from the book "The Home Cyclopedia Of General Information", by Charles Morris. Also available from Amazon: Home Cyclopedia of Necessary Knowledge.
The smallest of the planets except Mercury, and the nearest to the earth of the outer planets. It is of nearly 5,000 miles diameter, and about 142,000,000 miles from the sun. It is the only planet the details of whose surface can be seen from the earth, and presents interesting appearances not yet understood.
 
Continue to: