999: Other Worlds by Michael Lemonick

by Gerard

999: Lemonick, Michael D. Other Worlds: The Search for Life in the Universe. New York: Simon & Schuster, 1998. 255 pp. ISBN 0-684-83294-1.

At the very, very, very end of the Dewey Decimal Classification, you will find 999. The 900s are history and geography, and the 990s include history of other parts of the world. Normally, this would mean history of Australia and tiny island nations, but the last section—section 999—is reserved for the history of extraterrestrial worlds.

The only problem with writing about the history of extraterrestrial worlds is we have neither met any organism from another planet nor received any transmission from another planetary system. So, Michael Lemonick’s Other Worlds focuses on how Earth’s inhabitants are trying to find planets outside the Solar System.

All of this attention is due to the Drake equation, first posited in 1961. This equation was devised to try to calculate the number of extraterrestrial planets and the probability of interacting with them. The Drake equation goes like this:

N = R* x F(p) x N(e) x F(l) x F(i) x F(c) x L, where

N equals the number of civilization in our galaxy with which communication might be possible


R* is the average yearly rate of star formation is our galaxy,

F(p) is the percentage of those stars that have orbiting planets,

N(e) is the percentage of those planets that can support life,

F(l) is the percentage of those planets that actually have life,

F(i) is the percentage of those planets that have intelligent life and societies,

F(c) is the percentage of those societies that have developed technology to release radio signals, and

L is the length of time that those societies have had such technology.

It seems more complicated that it really is, but the current problem (at least for the time being) is refining our value for F(p) and N(e). We’ve got a passable fix on R*, but without those two you can’t really go further.

So, Lemonick traveled around the country, visiting with top-tier astronomers and cosmologists to gain a better insight into the ongoing experiments designed to help us gain a better understanding of the universe. From the Keck Observatory in Hawai’i to the many projects underway at NASA, he delves into both the mechanisms required to find extraterrestrial life and the implications for mankind in general.

The book has a more journalistic tone than a scientific one, but on the whole, this volume fits more in the 500s (science) than the 900s, but who am I to argue with the Library of Congress? I enjoyed it a lot, though. So much so, that upon buying a house, I plan to buy a decent telescope to investigate local astronomical interests.