SpectroscopyBy: Alex Ball
Spectroscopy is the detailed study of the light from an object and the interaction between matter radiated energy. The term spectroscopy refers to the scattering of an object's light into its component colors. By performing an analysis of an object's light, people such as astronomers can work out the physical properties of that object. These physical properties include finding the temperature, mass, luminosity and composition. It originated through the study of visible light distributed according to its wavelength. A great example of this is a prism. It is greatly used to incorporate any interactions of radiative energy as a function of its wave lengths or frequency.


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What is a Spectrometer?
A very important piece of technology that allows us to gather results and data for spectroscopy are spectrometers. These are instruments which spread light out into its wavelengths creating a spectra. Within these spectra’s people such as an astronomer can locate emission lines and absorption lines which are like the fingerprints of an atom and molecule. Emission lines take place when an electron drops downward into a lower orbit around the nucleus of an atom and starts to lose energy. An absorption line happens when electrons start to move into higher orbits by absorbing energy. Each of these distinctive atoms has a unique division of orbits and can only produce or soak up certain types of energy and wavelengths.This is the key explanation of why the positioning of spectral lines are different for every atom.
This is an example of a grating spectrometer


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  • You have a source of light or energy
  • The energy is reflected off of a mirror to a grating
  • The grating is used to determine the wavelength range of energy you want to use
  • The energy coming out of the grating is reflected off of a mirror to a detector
  • If you were to put some type of sample in the energy beam between the source and first mirror it would stop certain frequencies of energy from passing through
  • By examining which frequencies pass through the sample and which don’t you can verify what the sample is made out of


Spectroscopy Video




How spectroscopy is used in forensics?

A forensic analysis is a mixture of physical, chemical, and molecular methods to discover and determine the quantity and composition of particular compounds. Some of these techniques are highly accurate and is an excellent example of spectroscopy. Things such as the absorption, scattering, and emission of electromagnetic radiation are an essential component of spectroscopy. The steps of these functions go in order starting off with absorption. Absorption is the movement of electromagnetic energy from a beginning location to an atom or a molecule. The next step is scattering which is caused by the redirection of light because of its interaction with matter. The last function is emission which gets caused by the shift of electromagnetic energy from a one energy level to another. The result of this leads to the emission of a photon.

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How spectroscopy is used in astronomy?
Astronomical spectroscopy is another technique of spectroscopy which is used in astronomy. The primary factor in astronomical spectroscopy is the spectrum of electromagnetic radiation. This includes visible light which is produced from stars and other space bound objects. Astronomical spectroscopy can be used to determine numerous properties of distant stars and galaxies. These properties include things such as their chemical composition or what it’s made of, temperature, density, and its motion. From the study spectroscopy, astronomers are basically able to learn a massive amount of knowledge for an object in space.
How does Spectroscopy relate to society?
Spectroscopy relates to society in many different ways for example, its used in astronomy and discovering objects in space. It has successively contributed finding properties of space bound objects such as what it is made of, temperature, density, and its motion and rotation speeds of the object. From all this information it has given us I believe that spectroscopy has related there discoveries to society in a very positive way.


Glossary
Luminosity - The quality or state of being luminous

Spectra - A band of colors, as seen in a rainbow, produced by separation of the components of light by their different degrees of refraction according to wavelength


Emission - The production and discharge of something, esp. gas or radiation





http://en.wikipedia.org/wiki/Spectroscopy

http://loke.as.arizona.edu/~ckulesa/camp/spectroscopy_intro.html


http://www.ipac.caltech.edu/outreach/Edu/Spectra/spec.html

http://en.wikipedia.org/wiki/Spectrometer

http://en.wikipedia.org/wiki/Spectroscopy


http://www.youtube.com/watch?v=O39avevqndU