The search for planets
Lucas Ellerbroek: Planet Hunters. London: Reaktion Books,
2017, 267pp, £16.95
Shashi M. Kanbur
Ó Springer Science+Business Media B.V., part of Springer Nature 2018
Planet Hunters is a history of humanity’s search for planets outside our Solar
System and implicitly the search for life elsewhere in the Universe apart from Earth.
The book takes the reader from antiquity to the modern day: from Aristotle and
Aristarchus through Brahe and Kepler to Mayor and Queloz and the Kepler and
The book starts with an introduction to Giordano Bruno, perhaps the ﬁrst person
to consider an inﬁnite Universe and the prospect that other stars, like our Sun, may
have planets. Bruno was imprisoned, tortured, and ﬁnally burned alive in an attempt
to force him to recant his beliefs. Bruno was inspired by the work of Copernicus.
The author traces the origins of Bruno’s thinking from Copernicus to Aristotle,
though some of the contributions to the ‘‘Copernican revolution’’ from Islamic/
Indian/Chinese astronomers have been neglected in the book. The author then
devotes the next two chapters to a fairly detailed voyage through the history of this
ﬁeld, mentioning Tycho Brahe, Johannes Kepler, Galileo Galilei, Christian Huygens
and William Herschel.
The remaining eight chapters are devoted to the history of this ﬁeld in the last
100 years and cover the developments of SETI, the ﬁnding of the ﬁrst exoplanet, 51
Pegasi b, by Mayor and Queloz, to recent space-based mission plans to detect
planets in the habitable zone and possible extra-terrestrial life.
The author writes in an elegant, readable style that offers sufﬁcient technical
insight for the non-astronomer, but places the scientists and their work in an
appropriate societal and human context, and this is perhaps the main strength of the
book. There are a few places where the tense of a verb changes a bit abruptly. We
are treated to interesting vignettes about Bruno’s character, Brahe’s extravagant
lifestyle, the differing personalities of Brahe and Kepler, and the childhood that
& Shashi M. Kanbur
Department of Physics, SUNY Oswego, Oswego, NY, USA