Is There Life On Other Worlds?

I have acquired Poul Anderson's Is There Life On Other Worlds? (New York., 1963), the edition shown in the image. 1963 was also the year of Anderson's Thermonuclear Warfare, which I discussed recently. Thus, here is a second volume of non-fiction from the same period and relevant to even more of Anderson's fiction.

I will read and comment on this second work, starting with a statement on the first page of Isaac Asimov's Introduction. This process will take some time and will be interspersed with other activities. The cover informs us that the book "...ventures startling conclusions..." so let us be prepared to be startled. I welcome comments from blog readers whose knowledge of this subject is more recent than 1963. A great deal has been learned about other planetary systems in the last fifty years.