Dreams of Other Worlds: The Amazing Story of
Unmanned Space Exploration
By Chris Impey and Holly Henry
Princeton University Press (Princeton, NJ), 2012
This book is a thoroughly researched chronicle of
ten robotic missions, with an overview of the entire field of non-piloted
exploration. If it meanders a bit, it
succeeds at the most important task: showing readers just how remarkable our
robotic missions are. Impey is a professor of astronomy, Henry a professor of
English, and the combination of their expertise works very well.)
The Introduction sets the stage with the theorists,
from the Greek Anaxagoras to Copernicus to the modern day. For a long time, people have had the notion
there were other worlds to explore, but that was science fiction until 1957,
when it suddenly appeared practical to send machines (and eventually people) sailing
away from Earth.
The authors do, however, do a good job of featuring
all types of missions: planetary observer, rover, deep space, and
astronomical. They present two Martian
missions (Viking and Mars Exploration Rovers) first, followed by the probes
Voyager and Cassini, the comet-sampling Stardust, and SOHO, a mission to study
our home star. They break away from
voyages to specific destinations to cover Hipparcos, the Spitzer telescope,
Chandra, the Hubble, and the Big Bang explorer WMAP. It’s odd there are no Soviet/Russian missions
included, and Venus is left off the destination list. There are two European
Space Agency missions: Hipparcos, a 1989 mission dedicated to astrometry
(distances, locations, and movements of the stars) and Planck, along with the
joint Cassini-Huygens mission.
All the chapters on individual missions are good,
and the authors seem to know all about them.
Who knew 1,500 papers were published so far on the Cassini results? One aside here contains an error: the authors
say NASA’s “Faster, Better, Cheaper” initiative “launched 150 payloads at an
average cost of $100 million per mission, with a failure rate of less than 10
percent.” There were were 16, of which 10 accomplished their missions: even if
they are counting individual experiments vs. whole spacecraft, the numbers are
much too high.
The explanations of spacecraft design, function,
and results are succinct and well-done: clearly the authors understand the
technical side and have the ability to condense it in terms understandable to
the interested public.
There’s a tendency in this book to stray from the
main narratives in each chapter to explore topics as varied as extremophiles
and the history of X-rays. I enjoy this
kind of digression as long as there’s a connection: not all readers may
agree.
Finally, the authors look ahead. They describe the
hoped-for advances from the James Webb Space Telescope and future Mars probes, although
only NASA missions are addressed for some reason.
There’s a good color plate selection of 24 images and
some well-selected images in the text.
The references will make even the most detail-minded reader happy, and
the index is good as well.
This is, in short, a very valuable book, well
written and well documented. The selection of missions can be debated, but not
the quality of the coverage of those that did make it in. This is a must-have for anyone interested in
the robotic exploration of space, both closeup and from astronomical distances.
It will be valuable for a long time to
come.