Exoplanets | Planetary Zoo
surprised at the various types of life we find elsewhere. Every planet and every form of life will be unique and special. Such surprises are an exciting part of science. And we can expect many more surprises with the rapid pace of exoplanet discovery. And it may be that what we consider life is only one of a near-infinite number of possible types of emergent complexity in the universe. Some types of emergent complexity that we will find he past few years
T
out there might not meet many, or any, of the
have seen an incre-
generally agreed upon characteristics of life on
dible explosion in our
Earth, such as being based upon carbon; needing
knowledge of the uni-
liquid water; exhibiting reproduction, evolution,
verse. Since its 2009
and movement; etc. Yet those entities might be
launch, the Kepler satellite has disco-
BUY
vered more than 2,000
vastly more self-aware and sentient than we are. So looking for life as we know it may be the wrong approach. But the one lesson we have learned in our ex-
exoplanets, or planets outside our solar system.
ploration of the universe is the very same lesson
More exoplanets are being discovered all the time,
I learned when I first looked through a telescope.
and even more remarkable than the sheer number of
Every time we look beyond our ken we are aston-
exoplanets is their variety. In Exoplanets, astronomer
ished at what we see.
Michael Summers and physicist James Trefil explore
PA
these remarkable recent discoveries: planets revolving
About the Author
around pulsars, planets made of diamond, planets that
Michael Summers is a planetary scientist at George Mason University
are mostly water, and numerous rogue planets wan-
in Virginia and a co-investigator on NASA’s New Horizons mission to
dering through the emptiness of space. This captivating
Pluto. He specializes in the study of structure and evolution of plane-
book reveals the latest discoveries and argues that
tary atmospheres. His planetary research has dealt with the chemistry
the incredible richness and complexity we are finding
and thermal structure of the atmospheres of Io (one of the Galilean
necessitates a change in our questions and mental par-
moons of Jupiter), Titan (largest of Saturn’s moons), Uranus, Neptune,
adigms. In short, we have to change how we think about
Triton (largest moon of Neptune), Pluto, and Mars. Dr. Summers’
the universe and our place in it, because it is stranger and more interesting than we could have imagined.
research on the Earth’s atmosphere has focused on understanding middle atmospheric ozone chemistry, coupled chemical-dynamical-radiative modeling of active trace gases, heterogeneous chemistry
on meteor dust, the influence of solar variability on the state of the stratosphere and mesosphere, and polar mesospheric clouds and their connection to climate.
52
popularastronomy.com | Fall 2017