For thousands of years, the stars have been a constant source of wonderment and fascination for the human race. In fact, cave paintings over 15,000 years old depicting heavenly bodies were found in Lascaux, France in 1940. While primitive cultures had no tools with which to measure and study these points of light in the sky, we have since created several devices capable of looking closely at the stars and better understanding their nature.
The Reflector Telescope
Developed in the early 17th century by Niccola Zucchi and perfected later by Sir Isaac Newton, the reflector telescope is still in wide use today as the principal tool for studying stars. This telescope operates by bouncing light through a number of mirrors in a process called “folding the optical path.” The result is a short, fat telescope, which has better magnification ability than long barrel refractory telescopes. Reflector telescopes range in price from $250 to $5,000 and more, in 2010. What you can expect to see with a reflector telescope depends on the aperture size. A 4.5 inch aperture will show excellent views of the moon, other planets and even faint galaxies and clusters.
The Star Chart
Humans once used star charts to navigate while traversing the oceans. These star charts included all the directly observable formations in the night sky including constellations, clusters and the cardinal stars (e.g., the North Star.) Using these charts, sailors could tell where they were in relation to their home country. Today scientists using telescopes and other instruments are able to create detailed star charts, including stars invisible to the naked eye. These charts are used not to navigate the oceans, but to navigate the stars themselves with telescopes. The detailed charts provide a record of galaxies and other astronomical objects and provide more accurate dates for celestial sightings and events. Star charts can often be downloaded free from universities with astrophysics departments.
While reflector telescopes use light to show details in the night’s sky, radio telescopes use radio waves. These waves often provide greater detail and use computer telemetry to process very detailed images. One clear advantage of using radio instead of light is that radio captures an image that covers more than the entire light spectrum. This allows computers to filter out harsh light, which can obscure the details of a star’s inner workings. The result is not just a clear picture of a star's surface, but thermal images of a star’s core and even profile images of a star as it burns. Telescopes like this are responsible for discovering sunspots and seeing other phenomena such as black holes and supernovas that are not visible by some other star-studying devices.