Viewport width =
June 2, 2009 | by  | in Features |
Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

The History of Astronomy: A Primer

In The Beginning

Humanity has always had a strong fascination with the objects that inhabit the sky over our heads. They were quickly ascribed an elevated status, due to their perceived orientation above everything, and the idea that they were watching over and had influence on the Earth. Early religions centered around Sun and Moon worship, and celestial objects were believed to have a strong impact on seasonal changes such as rain and drought. From the beginning astronomy has had strong links to mysticism and religion, ones that it has struggled to divorce itself from for many centuries.

The first astronomers were in fact priests, who studied the heavens in order to gain divine knowledge of the gods and their earthly impact. While astronomy and astrology have very different meanings for us now, initially they were essentially synonymous, a mix of highly detailed observations of the sky with applied mysticism. As early as Babylonian times astronomy had begun to take on a more sophisticated and scientific approach, applying mathematics to predict cycles and patterns of planets’ and stars’ appearances in the sky. Most civilizations began using the sun and moon for timekeeping, especially those with an agricultural focus, constructing elaborate calendars based around their movements, dividing the year up into days, months and seasons. Early astronomical activity was largely observational, and still had a strong religious feel to it, both through its determination of rituals and festivals according to celestial movements and its adaptation to fit in with and expand the various religions’ explanations of the universe.

The Ancient Greeks took astronomy to a highly abstract level, developing complex three-dimensional models to explain the motion of the planets and stars, and even involved the creation of the Antikythera mechanism, one of the first examples of a computer, known for its incredible intricacy and miniature parts, possessing technology which was previously thought to have been invented in the 16th century. Greek astronomy first proposed the idea of the Earth rotating on its axis, and formulated several variations of a geocentric universe, with Ptolemy and Aristotle proposing that the Earth was at the centre of a universe that acted as a complex system of concentric spheres rotating around it in constant circular motion.

‘Well, actually….’

This model was largely accepted and became the standard view throughout most of the Middle Ages, and seemed to fit in with the intuitive view people held when they looked up at the sky and saw the movement of the stars, moon and planets, seemingly around their fixed location, the earth. The Catholic Church, the dominant power throughout Europe, accepted this view as it fit in with their conception of God’s creation of the universe around the Earth and Man. During the Renaissance, Nicholaus Copernicus proposed a heliocentric view of the universe, in which the planets (including Earth) revolved around the sun. While fragments of this theory exist as far back as the origins of geocentrism, Copernicus’s was the first to attempt to provide mathematical proof. As Schatzman says in The Structure of the Universe, this “caused a complete change in the astronomical outlook”, and tripped a major shift in scientific thought in general, serving as a starting point for the Scientific Revolution. Strangely enough, Copernicus only partook in astronomy as a part-time hobby, being more interested in his other endeavors in math, art and philosophy. Galileo Galilei, another prominent Renaissance polymath, expanded and improved Copernicus’s theory. While Copernicus’s theory remained strictly theoretical, Galileo argued that it was a proven physical reality, which made it much more provocative. Denounced by the Catholic Church, Galileo’s heliocentrism was met with much initial opposition, and Galileo was threatened, initially dropping his theory. When he later defended it he was swiftly tried and found guilty of heresy by the Roman Inquisition and sentenced to spend the rest of his life under house arrest. Ironically, heliocentrism was accepted reasonably quickly in the years after Galileo’s death. However it took until Kepler and then Newton’s discovery of celestial dynamics and laws of gravity to finally explain the true motion of the planets, which developed out of discoveries made possible by Galileo’s greatest contribution: the telescope.

Technological developments

The advent of new technology has played a massive role in astronomy’s development, with several important inventions producing great leaps in the astronomer’s observational capabilities, at times completely revolutionising the way that space is understood. Before Galileo, all astronomical observation was made with the naked eye, using elevated terrain and tall buildings as vantage points, along with limited use of instruments. Galileo wished to see space in more depth, and using the rough descriptions he had heard of Lippershey’s early telescope, made one of his own, quickly improving on the design and greatly increasing the magnification to 30x the naked eye. Using this he made many important observations, such as the discovery that Jupiter was orbited by its own moons, thus disproving the geocentric view that everything revolved around Earth. It is for this and his many other contributions to science, including his theory of the motions of objects and arguing for the mathematical precision of the laws of nature that both Stephen Hawking and Albert Einstein believe he is the father of modern science. The telescope has been greatly refined since Galileo, and telescopes can now observe on a variety of wavelengths outside the optical spectrum, which has in turn allowed for even more expansion and discovery. While other technological innovations such as photography and the invention and refinement of the computer have also had a large impact, the telescope more than anything else totally changed the way that astronomers observed space, and greatly expanded their conception of how incredibly large the universe really was.

Modern astronomy has a much stronger affinity with physics, and is split into two main sections: observational and theoretical astronomy. Theoretical astronomy uses complex computer models and calculations coupled with (now incredibly accurate) observations in order to make predictions and understand the behaviour of celestial objects. Theoretical astronomy asks many questions about the nature of the universe, such as its age, how it was created, and seeks to understand phenomena such as black holes, dark matter and cosmic inflation. The Big Bang theory is probably the most well-known modern astronomical theory, one that has gained wide acceptance (along with a continuation of the friction between astronomy and Christianity), and is fundamental to understandings of other modern theories. Observational astronomy mainly tries to find evidence to verify the theories, and the theoretical side also often helps to explain the new phenomena found by observers. The ever-popular search for extraterrestrial life is very much alive and well, and comes under the sub-classification of astrobiology, remaining strictly theoretical, and is popular with amateur observational astronomers.

Like Copernicus, many people engage in astronomy as a hobby, perhaps as a way to escape and travel beyond their daily lives, or because they are able to have an active role in astronomical development. Amateur astronomy has the advantage of being one of the only scientific disciplines whose enthusiasts still make regular important contributions. The constantly changing nature of observable space means that the huge amount of amateur telescopes pointed at the sky have a large role in collating variable data and making minor discoveries of new stars, comets and the like. Technological advancements have meant that amateurs are able to gain access to powerful equipment at reasonable prices, which has kept amateur interest steady since the massive boom in popularity of astronomy that came out of the public’s fascination with space activity in the 60s and 70s.

New Zealand and Astronomy

In New Zealand, amateur astronomy is hugely popular, and in fact has one of the highest astronomer-per-capita ratios in the world. Due to their geographic location, New Zealand astronomers are responsible for gathering information that is unique to the southern hemisphere. Marilyn Head, of the Royal Astronomical Society of NZ, says that as a nation New Zealand has made substantial contributions to astronomy. “The late Frank Bateson set up a huge network of amateur observers of variable stars and a system to ensure statistically reliable data, which provided astronomers with literally millions of observations of southern stars which were hugely important in understanding stellar processes.” This network still exists today, but instead of eyeballs, utilises CCD cameras to provide more constant and accurate information.

Professionally, New Zealanders hold many top astronomy-related positions, with Charles Alcock the Director of the Harvard-Smithsonian Institute of Astrophysics, Dick Manchester at the Parks Observatory in Australia (made famous in The Dish) and three of the eleven permanent astrophysics positions at Cambridge being held by Kiwis. Important discoveries by New Zealanders include work by Beatrice Tinsley, “who laid the foundations for modern cosmology (study of the universe as a whole) with her contribution to Stellar and Galactic evolutionary modeling,” and Gerry Gilmore, who “discovered the Galaxy’s thick disk, and the first example of galactic cannibalism within our galaxy”. For anyone interested in getting into astronomy, Head says that it is cheap at first, with a decent pair of binoculars and a star chart an easy way to start, but that “you do get addicted as there is a large number of things to get excited about—not only objects such as stars, galaxies, planets etc…but also techniques such as mirror grinding (producing your own telescope mirror from glass)”.

The Wellington Society holds meetings on the first Wednesday of every month at the Royal Society rooms and weekly Saturday night observations (weather permitting) at the Thomas King observatory. President Gordon Hudson says that everyone is welcome and they are always keen for new members, and that they are holding monthly talks at the Public Library as part of 2009 being the International Year of Astronomy, which would be a great place to begin finding out some more about the wonders of the universe that surrounds us.

2009 IYA

2009 has been declared by the UN to be the International Year of Astronomy (IYA), in order to coincide with the 400th anniversary of Galileo’s first use of an astronomical telescope. The aim of the Year is to stimulate general interest in the skies and astronomy, particularly young people, under the theme ‘The Universe—Yours to Discover’, and to provide greater awareness of the importance of the skies as a resource to be shared equally among all nations. Heaps of activities have been going on around New Zealand and Wellington, including the recent 100 hours of Astronomy and RASNZ conference held last weekend in Wellington. While these have passed, there are still plenty of activities to get involved in. A Galileo weekend is being planned for Labour Weekend and in October ‘The Great Worldwide Star Count’ is taking place all around the world. Anyone can get involved and the Wellington Societies will be holding activities as a part of this. In the meantime, the Wellington Library has set up several displays at the Library and around Wellington and is also holding monthly lectures and introductory talks about astronomy, which anyone can attend. Get out there and learn some cool stuff about the sky!

Further information

www.was.org.nz
www.rasnz.org.nz
astronomy2009.org.nz

Share on FacebookShare on Google+Pin on PinterestTweet about this on Twitter

About the Author ()

Comments are closed.

Recent posts

  1. Am I my skin?
  2. The Trauma of the Non-Voter
  3. Marshall Islands deliberate whether to ban nuclear weapons
  4. Vanity Fair — W. M. Thackeray
  5. Her Legacy
  6. GIG GUIDE
  7. The Fury of [our] own Momentum: Twin Peaks, Protest, and the Bomb
  8. VUWSA
  9. Editors’ Letter
  10. Mario + Rabbids Kingdom Battle
brigid

Editor's Pick

I’m Not Sure How I Feel: Disillusionment With Elections

: - SPONSORED - This post-election sentiment was written prior to the election, due to both the limitations of print and the pervasiveness of this disillusionment beyond the election’s outcome. If there was a revolution over the weekend, some of these thoughts can be disregarded.