Viewing The Universe
Descriptive vocabulary
What is Astronomy?
Astronomy is the study of the universe,galaxies, and our solar system. For example, the study of astronomy is important because scientists could make exciting discoveries such as, planets, stars, black holes, and nebulas. Astronomy is also used to protect the earth from meteors or collisions
Objectives
1. Identify the visible and nonvisible parts of the electromagnetic spectrum.
2. Compare refracting telescopes and reflecting telescopes.
3. Explain how telescopes for nonvisible electromagnetic radiation differ from light telescopes.
Astronomy Vocabulary
Light year
A light year is a unit of length equal to just under 10 trillion kilometers.
Galaxy
A collection of stars, dust, and gas bound together by gravity.
Astronomical unit
The average distance between the Earth and the sun; approximately 150 million kilometers.
Electromagnetic spectrum
All of the frequencies or wavelengths of electromagnetic spectrum.
Refracting telescope
A telescope that uses a set of lenses to gather and focus light from distant objects.
Reflecting telescope
A telescope that uses a curved mirror to gather and focus light from distant objects.
Electromagnetic spectrum
The electromagnetic spectrum is a list of types of radiation. The list shows from the least to most dangerous. An example of a dangerous radiation is gamma rays. Another example is the least dangerous it is X-rays. Most of this radiations are located in space and can be found by space telescopes. The electromagnetic spectrum also consists of wavelengths and frequencies.
Compare refracting and reflecting telescopes
To start out the paragraph you should know that both telescopes are optical telescopes. A refracting telescope has an objective lens that bends light that passes through the lens and focuses the light to be magnified by an eyepiece. One problem with the refracting telescope is that the lens focuses different colors of light from different distances. If an object would focus in a red light, the object will appear out of focus in blue light. Another problem with the refracting telescope is that it is very difficult to make very large lenses. Unlike reflecting telescopes, reflecting telescopes doesn't have any problems. The reflecting telescope also uses a different kind of lens a curved mirror. When light enters the reflecting telescope, the light is reflected by a large curved mirror. The reflecting telescope also has a second mirror that reflects light to the eyepiece. Unlike objective lenses in refracting telescopes, mirrors in reflecting telescopes can be made large without affecting the quality of the image. The reflecting telescope is larger and could gather more light than refracting telescopes.
Invisible telescope
The invisible telescope can only attract radiation. Radiation travels to earth and powers the electronics. The radiation can't be seen by the telescope. Water vapor and clouds blocks the telescopes view and prevented it from gathering information. The best way to collect information with the invisible telescope is to put it in a high height or in space.
Space telescope
Space telescopes can collect more data than the ones located from earth. Also space telescopes can take clear images. Some telescopes were sent to space to detect gamma rays. Another telescope they sent to space was a scope to detect infared radiation. These telescopes are used to take pictures of the universe and to examine new things. The telescope in this photo is a famous telescope of the Hubble.