Steller Guides
Written by Cece, Lea and Zariah.
What is spectroscopy?
Spectroscopy is a scientific measurement technique. It measures light that is emitted, absorbed, or scattered by materials and can be used to study, identify and quantify those materials.
A spectroscope is an instrument used to separate visible light into its spectrum. While using a prism, it refracts light into its colors.
What are spectral lines?
Astronomers are able to identify the different gases found in stars based on its spectrum. Depending on the width of spectral lines astronomers can tell how fast the material is moving.
There are three different types of spectral lines:
- Continuous Spectrum.
- Absorption Spectrum.
- Emission Spectrum.
1. Continuous
This spectrum has an unbroken band of colors. It comes from glowing solids or hot compressed gases. It doesn't always have to be all seven colors, which consist of
2. Emission
This spectrum is a bright line spectrum. It consists of unevenly spaced dark lines on a dark background. It occurs when glowing gases send certain wavelengths (ex. gas tube). Each gas has its own signature spectrum.
3. Absorption
This spectrum is a dark line spectrum. It consists of unevenly spaced dark lines on a colored ground. It occurs when gas passes through the cooler outer layer of the star.
How is spectroscopy helpful?
Spectroscopy is useful in helping scientists understand how objects such as black holes, neutron stars, or an active galaxy produces light and how fast it is moving.
How are elements identified in stars?
The elements in a star are identified using the technique of
spectroscopy. The analysis of the radiation (light) coming from a star
will identify the elements in that star.
What different elements are in a star?
Did you ever wonder what stars are made of? Stars are made of the same material as the rest of the Universe: 73% hydrogen, 25% helium, and the last 2% is all the other elements. That’s it. Except for a few differences here and there, stars are made of pretty much the same material.
Hydrogen- 73%
Helium- 25%
Nitrogen- 2%
Carbon- 2%
Oxygen- 2%
Silicon- 2%
Example: The Sun.
Work Cited
http://www.madsci.org/posts/archives/2000-03/952547619.As.r.html
https://solarsystem.nasa.gov/deepimpact/science/spectroscopy.cfm
http://www.universetoday.com/24796/what-are-stars-made-of/
http://www.physics.org/article-questions.asp?id=52
http://imagine.gsfc.nasa.gov/science/toolbox/spectra1.html
geoscience notes
google images for pictures