The History of Astronomy
and Astrophysics: A Biographical Approach
is the oldest of the natural sciences, with its origins
in the religious, mythological, and astrological practices of
pre-history. Originally, peopled gazed at the sky and speculated
about the nature of the Moon, the Sun, and the stars.
and nature of the world and celestial phenomena came to be explained
by invoking the actions of the various gods. Then, one god became
the explanation for both. And then explanations for earthly events
began to be accepted based on speculation as to their cause and
nature, while celestial events were still felt to be of a divine
nature, requiring no explanation. Eventually, human beings began to
look for scientific explanations for both. Early on, the Earth was
considered to be at the center of a celestial sphere, with the
Sun, Moon, stars, and
located on the surface of the sphere.
invention of the telescope about 400 years ago opened new avenues of
research and speculation. The Sun and the Moon could be scrutinized
in greater detail, and new planets came to be identified and
studied. Slowly, the concept that Earth was not the center of the
universe took hold, and eventually the notion that the Milky Way is
but one of millions of galaxies became accepted.
Speculation about life on the Moon and other planets became a hot
topic. Some believed it a possibility; others felt it to be a fact,
identifying what they felt to be canals on Mars and cities and even
buildings on the Moon.
New investigative tools,
such as spectrometry and photometry, were developed for determining
spectral characteristics and brightness, respectively, of
cosmological objects. Then scientists began to look at the skies,
detecting electromagnetic radiation other than visible light, such
as infrared and X-rays. Others studied cosmic radiation, including
background microwave radiation, neutrinos produced within the Sun,
and ions of various elements.
Theories about the
evolution of the universe were developed, the two most prominent
being the steady-state theory and the Big Bang theory. According to
the steady-state theory, the universe has no ending and no
beginning. As the universe expands, new matter is created so that
the average density stays the same. The Big Bang theory, on the
other hand, views the universe as being created approximately 13.7
billion years ago by a violent explosion. At the point of this
event, all of the matter and energy of space was contained at one
point, a singularity. The universe is seen to still be expanding
from the explosion.
Although the great body of
knowledge we now call astronomy and astrophysics has come into being
because of the work of astronomers and astrophysicists, many
individuals from other disciplines have contributed, including those
from mathematics, physics, engineering, and chemistry. Many of the
earlier astronomers made significant contributions without having
the benefit of a formal education.
To those who made
significant contributions to astronomy and astrophysics, and I
inadvertently left them out of this book, I humbly apologize.
Those individuals whose
contributions have been mainly physics are notably absent. An
additional volume, The History of Physics, was
published earlier this year.
I have chosen to approach
the history of astronomy and astrophysics from a biographical point
of view, feeling that people are more interesting than things, and
the combination of the two are more interesting than the sum of the
individual parts. After a brief overview of astronomy and
astrophysics, 297 one-page biographies of individuals who have made
significant contributions to the field of astronomy and astrophysics