Discribing the Universe
In terms of times, distance and organization.
The Value of Astronomy
The value of astronomy helps us study new planets, stars, black holes, and nebulas and how to protect the earth if an emergency would happen. For example if an asteroid were to have a collision with earth.
Objectives
- Identify the visible and nonvisible parts of the electromagnetic spectrum.
- Compare refracting telescopes and reflecting telescopes.
- Explain how telescopes for nonvisible electromagnetic spectrum.
Vocabulary
Universe
The universe is everything in space planets, stars, nebulas,black holes etc.
Astromical unit
The average distance between the earth and the sun; approximately 150 million kilometers
Light year
A unit of astronomical distance equivalent to the distance that light travels in one year
Electromagnetic Spectrum
All of the frequencies or wavelengths of electromagnetic radiation
Refactoring Telescope
A telescope that uses a set of lenses o gather and focus light from distant object
Reflecting Telescope
A telescope that uses a curved mirror to gather and focus light from distant objects
Describe the Electromagnetic Spectrum
The electromagnetic spectrum is all of the the wavelengths of electromagnetic radiation. Both visible and invisible light is energy from stars.They travel at the same same speed. Both are electric and magnetic fields. They are radiation and travel though waves. Visible light is when light passes through a prism the light breaks into sets of colors. The shortest wave lengths are blue and violet. Longest wave lengths are orange and red. Every wave length has a different color. Invisible light are waves that are shorter than violet and longer than red and cannot be seen by the human eye. Invisible waves include microwaves, radio waves, ultraviolet rays, x-rays, and gamma rays. If you want to see the invisible waves you need a special instrument.
Comparing Refracting and Reflecting telescopes
Refracting and reflecting collect only visible light. Both of them are optical telescopes. The light magnifies the eye pice in both the refracting and reflecting. The refracting telescope contains lenses that are clear. Theses lenses bend the light. The lenses focuses on different colors of light at different distance. One problem this telescope has is that the lenses can't be made very large by the the required strength and quality. The reflecting telescope uses curved mirrors togather the focus light from distance objects. The mirrors can be made very large and dose not affect the quality of the image. It can gather more light than the refracting telescope.
Invisible Light Telescopes
Scientist have develped telescopes that are ground based and use for studying gamma rays, ultraviolet, inferred rays, and x-rays. This ground based telescope works better at high elevations. One problem this telescope has is that it can't gather that much rays because the earths atmosphere acts like a shield. The water vapor in the atmosphere prevents gamma rays, x-rays, infrerred rays, ultraviolet rays from reaching earth.
Space Based Telescopes
A space craft has been launched to study planets, stars, and distant objects. The hubble space telescope has been launched to collect electromagnetic radiation from objects in space. Chandra x-rays observatory make clear images using x-rays from objects in space. Compton gamma rays observatory detect gamma rays from black holes. James Webb space telescope will detect inferred radiation.