Stars and Telescopes

Stars and Telescopes

Rae Wiens

SCI151

June 15, 2015

Benjawan Kjornrattanawanich

Stars and Telescopes

“Telescopes are our primary tool for studying distant objects, enabling us to see phenomena too dim for our naked eyes and to observe wavelengths of light that our eyes cannot detect” (Pearson Education, 2006). The invention of the telescope has allowed humans to view the universe in a new way and rediscover our place in it. The two main types of telescopes are the refracter and the reflecter. Scientists have specific reasons and places where ground-based telescopes are built. Ground-based telescopes on Earth, telescopes in Orbit, and telescopes on the moon all have their individual advantages and disadvantages. Different frequencies of light can help determine the birth, life, and death of the sun, stars, and the universe. Telescopes operate on several different forms of electromagnetic radiation ranging from radio waves to gamma rays.  
                                   Telescopes and Our View of the Universe

Over that past 400 years the invention of the telescope has continued to change our view of the universe (Vlahos, 2010). Galileo Galilei invented a telescope that helped prove that our universe was much larger than ever thought of, and our place in it much smaller than imagined. Telescopes helped prove that the Earth is not the center of the universe, showed mountains and craters on the moon, revealed weather and geography of other planets, discovered other celestial objects (like asteroids), measured the speed of light, helped understand gravity, and how light radiates form the sun and stars (JPL Education, 2010).

         Refracter and Reflecter

“The refracter telescope uses a lens to gather and focus light” (Strobel, 2011). These were some of the first telescopes ever made. An advantage is that it rarely needs to be cleaned because it is sealed tightly. Their optical system is also more resilient to misalignment (Strobel, 2011). Images are often clearer because outside forces like air and temperature cannot reach it. However, the disadvantage is that all refractor telescopes suffer from chromatic aberration (color deviation and distortion) (Strobel, 2011). Ultraviolet light cannot pass through the lens, thickness of the lens is decreased, and lens has imperfections.

“The reflector telescopes uses a mirror to gather and focus light” (Strobel, 2011). A big advantage is that they do not suffer from chromatic aberration. Objects can be made very big, they are cheaper, and just one side needs to be perfect. However, a big disadvantage is that is can easily get out of alignment. It also requires frequent cleaning because it is not concealed form outside forces. It needs a secondary mirror, which can produce diffraction affects; bright objects have spikes (Strobel, 2011).