Telescopes are one of the greatest inventions and have led scientists on a fantastic journey of getting closer to understanding the universe. There is no way to research and evaluate outer space without telescopes gathering all of the information that they do. This paper is going to discuss the science of telescopes and explain all of the elements relative to them. How telescopes changed our view of the universe Without telescopes, our view of the universe is quite small and limited to what our human eyes can show us.
Having the ability to see further into space can give us a greater perspective as to our place in the universe and what else is out there. There are many telescopes used to improve our knowledge of the universe but one of the greatest would be the Hubble Space Telescope. The Hubble telescope was set to orbit the Earth in April, 1990 and has acted as a rollercoaster of information. It has provided some major breakthroughs including the Hubble Ultra Deep Field, the age of the universe, and planets in our own solar system.
In 2003 and 2004, scientists pointed the Hubble telescope into two parts of space that had no objects, just blackness (about the size of a grain of sand). This was an extreme risk of wasting the telescopes viewing power and time, but the result was incredible. This provided us with the furthest look into space we have ever seen and a glimpse at over 10,000 other galaxies in the universe just in those two looks (Nunes, 2012). Major designs of telescopes There are two major designs of telescopes called refracting and reflecting.
Refracting telescopes were the first type of telescope invented and work like an eye where a glass lens is used to focus light. There are a few weaknesses to using a refracting telescopes, one being that the glass used for the lens must be perfectly clear and shaped in order for the light to pass through the lens. The second weakness is that large glass lenses are very heavy and must be at the top of the telescope making it hard to stabilize (Bennett, Donahue, Schneider, & Voit, 2010).
Reflecting telescopes use multiple mirrors to focus the light on a specific place we want to observe. The primary mirror gathers the light that reflects onto the secondary mirror that puts the light where we need it. The majority of scientific telescopes used for research currently are reflective telescopes. There are some strengths to using reflective over refractive telescopes. The first being that because they use mirrors over glass lenses, they don’t have to be perfect because the light bounces off of them instead of going through them.
The second being that the primary mirror is on the bottom of the telescope making it easier to balance than a refractive telescope (Bennett, Donahue, Schneider, ; Voit, 2010). Best places to build ground-based telescopes Ground-based telescopes have many advantages including the affordability of building and maintaining it, but is not the most favorable place to observe space. The Earth’s atmosphere also presents some challenges to ground-based telescopes including the daylight, bad weather, man made light, and many others.
Some good places to build ground-based telescopes include very low populated areas in order to help avoid man made light, high-altitude, and drier climates places to avoid clouds and bad weather. Telescopes on Earth, in orbit, or on the Moon Telescopes can be built on Earth, put into orbit around the Earth, or set up on the moon. Some reasons astronomers choose to put telescopes into orbit or on the moon is to avoid the previous mentioned problems that Earth’s atmosphere presents.
The strengths of putting telescopes into orbit like the Hubble Space Telescope, is not only to avoid all of those challenges but to be closer to the objects we wish to observe. Some objects like planets, only emit a small amount of light that cannot reach Earth’s surface. This is why telescopes in space are such a great advantage. The moon would be a great spot to build a telescope, however astronauts can only take so many materials with them so they are currently studying how to build the remaining parts of the telescope out of moon dust (Naeye, n. d. ). What different frequencies of light tell us. There are also telescopes that observe other type of light frequencies. One, known as neutrino, is a product of nuclear reactions and can be a sign of a star explosion. Different frequencies can also tell us the temperature of a star, and if that temperature changes, it could be a sign of a planet orbiting it. Telescopes operate in wavelengths of light Most scientific telescopes are reflective telescopes using mirrors to reflect light, and in order to see invisible light scientists must alter the original design to detect radio waves, infrared waves, ultraviolet light, X rays, and gamma rays.
Depending on the type of light that scientists are trying to observe, the telescope will be built differently to interpret their wavelengths. Radio wavelengths Radio wavelengths are long which requires that radio telescopes must be larger to receive them. The problem with radio waves is that there are so many from society being used that they can easily get crossed. Scientists hope to someday set up radio telescopes on the moon to avoid this (Bennett, Donahue, Schneider, & Voit, 2010).
Infrared wavelengths. Infrared wavelengths are quite comparable to visible light, so infrared telescopes are very similar to regular reflective telescopes. Most infrared telescopes are positioned at higher altitude places because the light hardly reaches Earth’s surface (Bennett, Donahue, Schneider, ; Voit, 2010). Ultraviolet wavelengths Ultraviolet light wavelengths are also similar to visible light, however, “Earth’s atmosphere almost completely absorbs ultraviolet light, making most ultraviolet observations impossible from the ground” (Bennett, Donahue, Schneider, ; Voit, 2010, p. 88). To get around this, there are two main observatories in space to monitor ultraviolet wavelengths (Bennett, Donahue, Schneider, ; Voit, 2010). X ray wavelengths X rays are harder to observe because they go through almost any surface including mirrors. X ray telescopes are mostly made up of grazing incidence mirrors which allow the x rays to only graze the mirrors so they bounce off onto the focal plane (Bennett, Donahue, Schneider, ; Voit, 2010).
Gamma ray photons. Gamma rays are the hardest to focus because they can even pass through grazing incidence mirrors. In order to capture them, it takes a very large detector. “For example, the Large Area Telescope on the Fermi Gamma-Ray Observatory weighs 3 tons… ” (Bennett, Donahue, Schneider, ; Voit, 2010, p. 188). Conclusion Telescopes come in many different shapes and sizes and play major roles in the education of our universe. As technology increases, telescopes will become more powerful giving us a bigger advantage in learning what goes on in the cosmos. This paper explained the science of telescopes and discussed the many factors that they contribute to astronomy.
Bennett, J. , Donahue, M. , Schneider, N. , ; Voit, M. (2010). The cosmic perspective (6th ed. ). San Francisco, CA: Pearson Education, Inc.. Naeye, R. (n. d. ). NASA. Retrieved from http://www. nasa. gov/centers/goddard/news/topstory/2008/lunar_telescopes. html Nunes, G. D. (2012). HubPages. Retrieved from http://gdnunes. hubpages. com/hub/Hubble-Space-Telescope-A-Journey-From-Embarrassment-to-Excellence