Amateur Astronomy

History

Amateur astronomy is a hobby concerned with finding and observing stars, planets and other astronomical bodies and phenomena. There are thousands of hobbyists and hundreds of organizations dedicated to the development of amateur astronomy, or "stargazing."

Astronomy originated in the earliest human civilizations and developed independently in cultures around the world. As humans developed agriculture, the interpretation of astronomical phenomena became an important tool for predicting patterns in climate and weather.

Early Chinese, Sumerian and Egyptian cultures began to keep detailed records of objects in the heavens as early as 6000 BCE. This led to the invention of the calendar. The Sumerians and the Babylonians are credited as the first to use astronomy in the development of the concepts of the year, day, month and hour.

Archaeological sites such as England's Stonehenge indicate that Paleolithic Europeans were beginning to use the sun and the stars to create temporal and seasonal maps as early as 5000 BCE.

Modern astronomy has its roots in ancient Greece. Greek philosophers added mathematics and scientific rigor to the study of stars and constellations. Around 310 BCE, the astronomer Aristarchus of Samos was the first to suggest that the earth rotated around the sun.

Although glass was discovered by the Phoenicians around 3500 BCE, it was not refined for use in magnifying instruments until the sixteenth century CE. Dutch lens maker Hans Lippershey created the first practical telescope and made it available for public use in 1608. Shortly thereafter, Galileo Galilei became the first scientist to use a telescope to observe stars and planets. Galileo was the first to view the rings of Saturn, the moons of Jupiter, and the phases of Venus.

In the late seventeenth century, English physicist Isaac Newton invented a new method of capturing light for telescopes using a curved mirror, called a reflecting telescope. Newton's design increased the magnification of telescopes by several orders of magnitude, and became the standard for telescope design for the next two centuries.

William Herschel discovered Uranus in 1781 using a telescope. Herschel went on to discover infrared radiation and was the first to describe two of the satellites orbiting Saturn. Herschel's sister, Caroline Herschel, was a professional astronomer who catalogued stars and nebulae, and discovered eight comets. In 1846, Neptune was discovered by German astronomer Johann Galle.

In Victorian England, the practice of amateur astronomy gained popularity among the social elite. Wealthy amateurs commissioned observatories and telescopes and made substantial contributions to the field. Amateur observers in England discovered comets, asteroids, and planetary satellites.

In the late nineteenth century, astronomy spread to other levels of society. Dozens of organizations and social clubs formed to share equipment, information and inspiration.

The lines between amateurs and professionals continued to blur throughout the twentieth century, as telescopes became more easily obtainable by the general public. The invention of radio telescopy and powerful space telescopes represented significant advances in the science of astronomy.

In the twenty-first century novice astronomers may purchase powerful telescopes for recreational use, and many volunteer to assist in observations with local or national science teams. Amateur astronomers have advantages that professional astronomers may not have, such as the freedom to choose when and where to make their observations. Organizations such as the American Association of Variable Star Observers (AAVSO) and the Center for Backyard Astrophysics (CBA) allow skilled amateurs to communicate and collaborate on research projects. Both organizations serve as repositories of data collected by amateur astronomers. The Society for Astronomical Sciences hosts an annual symposium on small-telescope astronomical research.

Types of telescopes and mounts

• Reflector telescopes: Reflectors (or Newtonian reflectors) use mirrors to reflect light and are generally the most inexpensive type of telescope. Reflectors are sturdy and relatively easy to transport, and are ideal for viewing nebulae, planets and comets.
• Refractor telescopes: Refractors use a series of lenses to magnify images, and generally have small apertures. Refractors are excellent for viewing detail such as planetary surfaces. Because refractors require several thick lenses, they are more expensive than most reflecting scopes and are often heavier and more difficult to transport.
• Catadioptric telescopes: Catadioptrics use a combination of powerful lenses and mirror reflection to optimize magnification and clarity. They are generally more expensive than reflectors and less expensive than refractors, and provide a mid-range for perception. Catadioptrics have become the most popular choice for astrophotography.

• Equatorial mount: The most common type of mount for both refractors and reflectors; the equatorial mount is designed like a globe with two axes for declination and ascension. Equatorial mounts allow objects to be located by their coordinates and allow astronomers to track the movement of objects through the sky.
• Dobsonian mounts: The Dobsonian mount is designed for heavy telescopes and generally made of wood or metal. Dobsonian mounts do not allow for tracking objects by coordinates. Some amateur astronomers construct their own telescopes and generally use a Dobsonian design for the mounting structure.

Other equipment

• Star charts and books: Star charts map constellations based on the location of the observer and may also contain information about seasonal and temporal variations. Some charts and books also contain information about viewing planets, comets, meteors and planetary satellites.
• Filters: Telescope manufacturers have also designed filters to block out wavelengths of light that interfere with viewing specific objects. Solar filters are designed to allow astronomers to view the sun directly without damaging the eyes. Colored filters are chosen to make specific details stand out. Certain filters will allow the astronomer to view planetary rings, satellites and surface features in more detail.

Amateur Astronomy for Fun vs. Profit

Amateur astronomers looking to turn their hobby into a career may want to seek further education in physics from a university or astronomy organization. With a background in basic physics, a dedicated amateur can use his or her knowledge to instruct novice astronomers. Skilled amateurs can teach classes through astronomy organizations or at certain institutions of higher learning.

Alternatively, amateur astronomers can find employment by aiding in research as a consultant or research associate for professional scientific organizations. Amateurs can also serve as tour guides, helping novices to locate the best sites for stargazing.

Amateur astronomers who make significant contributions to astronomical research may be recognized for their work by amateur and professional astronomical organizations. The Astronomical Society of the Pacific bestows the Gordon Myers Amateur Achievement Award (formerly known as the Amateur Achievement Award), a prize of $500, annually. The American Astronomical Society grants the Chambliss Amateur Achievement Award annually.

Learning More

Organizations

American Association of Variable Star Observers (AAVSO) <www.aavso.org>

American Association of Amateur Astronomers (AAAA) <www.astromax.org>

American Astronomical Society <https://aas.org/>

Astronomical Society of the Pacific <https://www.astrosociety.org/>

Center for Backyard Astrophysics (CBA) <https://cbastro.org/>

National Aeronautics and Space Association (NASA) <www.nasa.gov>

Society for Astronomical Sciences <http://www.socastrosci.org/>

Books

Dickinson, Terrence and Alan Dyer. The Backyard Astronomer's Guide. Firefly Books, 2002.

Sherrod, P. Clay and Thomas L. Coed. A Complete Manual for Amateur Astronomy: Tools and Techniques for Astronomical Observation. Dover Publications, 2003.

Bakich, Michael, E. The Cambridge Encyclopedia of Amateur Astronomy. Boston: Cambridge University Press, 2003.

North, Gerald. Advanced Amateur Astronomy. Boston: Cambridge University Press, 1997.

Periodicals

Sky & Telescope: The Essential Guide to Astronomy <https://www.skyandtelescope.com/>