How We Learn About the Universe

By Glenn A. Walsh,

Past Astronomical Observatory Coordinator,

The Buhl Planetarium and Institute of Popular Science, Pittsburgh

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Thousands of years ago, men and women looked up at the sky and pondered the meaning of what they saw. They quickly learned that some sky objects, such as the Sun and the rain, were vital to their lives. They wondered if the tiny lights in the nighttime sky also had meaning in their lives.


This led to people creating myths about the constellations or star pictures. As more star patterns were identified, astrology, the study of how the stars affect people’s lives, began.  Astrology was often part of religious beliefs.  It led to the study of the universe called astronomy.


Early astronomical observatories, such as the famous Stonehenge in England, show that early sky watchers knew more than we realize.  Their observations led to the development of calendars, clocks, and watches.


The invention of the telescope in 1609, completely changed astronomy.  It allowed Galileo and others to make detailed observations of objects that had previously been a mystery. Soon, telescopes became larger, and helped people view more distant objects with greater detail.  This new knowledge increased the understanding of the Universe.


Nineteenth century astronomer Samuel Pierpont Langley developed a New Astronomy, which became known as astrophysics.  This science measures space objects to analyze how they are constructed. New instruments, such as the spectroscope were developed to analyze the light coming from stars to determine their composition.


Another revolution in astronomical research came 50 years ago with the launch of unmanned space probes by Russia and the United States. We’ve sent many probes such as Voyager I or II to the outer planets of our solar system - Jupiter, Saturn, Uranus, and Neptune.  It has been said that each time a probe passed a planet we learned more about it in just 24 hours than had been learned in all of previous history!


We haven’t just sent robots into space. Since 1961, men and women have started traveling into space for even more detailed exploration. On July 20, 1969, astronauts Neil Armstrong and Buzz Aldrin were the first of twelve Americans to explore the Moon’s surface. Current plans are for more astronauts to return to the Moon within the next twenty years, and to Mars later on. (See the related article, Fly Me to the Moon, in the Geography section of this issue of Spigot.)


Scientific exploration is not the only reason why people explore outer space. As the world population grows, it becomes harder to find food and materials to support all the people. We need to find new resources, and space may have new resources to help us on Earth.


You can learn more about astronomy and space sciences in several ways. The Internet is a wonderful resource; however, you have to be careful that the information on web sites is correct. One way to be sure information is accurate is always to use web sites of major scientific organizations, such as NASA and universities. Books, journals, and other publications in public libraries are also wonderful resources for finding correct scientific information.


A planetarium, science center, museum, and astronomical observatory are great places to get good information about astronomy. Ask at your public library or planetarium whether there is an amateur astronomers stargazing club in your area or where the closest planetarium or museum is.  Librarians love to help you learn.


There is so much to learn about astronomy and its related fields.  It will play a very important part in our future, so be part of the fun and learn more about stars, planets, and space objects by studying astronomy.