OVERVIEW
2015 LASSI Professional Development STEM
WIRO ADVENTURE
ANNETTE MASON, LISA JOHNSON & SAM KRAMER
Through our observations at WIRO we collected spectra data from
stars, quasars and galaxies. Using the data we graphed the
information. By observing the absorption and emission lines we
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were able to identify what each spectra represented. Through
further research we were able to determine the temperature,
composition, velocity and direction of each object.
PARTICIPANTS
FINDINGS
Spectra show a variety of information. We can learn the temperature (how hot something is), the composition (what something is
made of) and the velocity (how fast it is moving) from spectra.
We found that lines in the graphs represent absorption and emission. Absorption spectra lines represent material between the
observer and object like gas or dust. (Kirchoff ’s law pt. 2). Emission lines represent atoms or molecules transitioning from high
energy state to a lower energy state (Kirchoff ’s law pt.3). A star spectra will show absorption lines, while a galaxy will show flatter
spectra with absorption and emission lines. A quasar will display broader emission lines due to its orbit around a black hole or other
object.
To tell the temperature of an object you observe the highest emission point and see where that is on the spectra. If it is closer to
the blue it will be hotter than our sun. If it is closer to the red it is cooler than our sun. Our sun is in the middle of the spectra.
The specific wavelengths in the lines will tell the chemicals in that object. These chemicals make up the composition of the
object.
As we look at the same object over time we can see if the spectra is moving to the red or the blue. We can compare this to the
object as if it was standing still. From this information we can determine the velocity by looking at z (the red shift) x the speed of
light.
Hot stars are relatively young and will burn up quickly. They are usually made up of hydrogen and helium. Red stars are cooler
and will be around forever. They contain a lot of different elements that burn slower.
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RESULTS
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Series1
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References: http://www.sdss.org/, Dr. Ryan Hickox, University of Wyoming: Dr. Adam Myers, Dr. Mike
DiPompeo, Will Chick, Cody Minns
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