A Student Investigation

I came across this study (http://www.lexington.k12.il.us/students/ajohanse/Experiments.htm) by Mr. Steve Simpson (ssimpson@lexington.k12.il.us) and his students at Lexington High School in Lexington, Illinois. Simpson has BA from Sul Ross State University ( ca 1996?) and on 3/28 - 3/30, 1999. Here is what they did, and what they concluded:

Spectroscopy By: Amanda Johansen, Jessica Schneider, Chelsea Thomas I. Objective We are going to use a spectroscope to determine what the Marfa Lights really are. We have to match the wavelengths and frequencies, as well as the color and appearance, with our own light samples we take to determine what kind of light is being given off. Once we determine the type of light given off, we can better explain what is causing the light and where it is coming from.

II. Discussion We found out that the basis of spectroscopy is that each chemical element has its own characteristic spectrum. The prism spectroscope consists of a slit for admitting light from an external source, a group of lenses, a prism, and an eyepiece. The light passes through a collimating lens, which makes the light rays parallel. Then the image of the slit is focused at the eyepiece. You then see a series of images, each a different color, because the light was separated into its component of colors. When light from a glowing element is analyzed through a spectroscope, it is found that the colors are the composite of a variety of different frequencies of light. The spectrum of an element appears as a series of lines. Each line corresponds to a distinct frequency of light. Each colored line appears in the same position as that color in the continuous spectrum. An emission spectra consists of all the radiations emitted by atoms or molecules, whereas an absorption spectrum, portions of a continuous spectrum are missing because they have been absorbed by the medium through which the light has past; the missing wavelengths appear as dark lines or gaps. We will most likely encounter the absorption spectra.

III. Materials - Meade Model 2045 4" Schmidt-Cassegrain Telescope - Rainbow Optics Star Spectroscope - Hydrogen Tube - Helium Tube - Mercury Tube - Maglight (flashlight) - Red lense - Blue Spectroscope (cheap) - Spectroscope Decoder and Directions - Camera (use 35mm film) - Colored Pencils - Pen and Paper (to record results and ideas) - Tripod - Power Supply IV.

Procedure We plan on going out on separate occasions and viewing the different kinds of lights such as headlights, taillights, street lights, and fog lights. We will also be looking at hydrogen, nitrogen, and helium lights. We will record our results by either taking pictures or drawings. We are able to view these lights by a man-made object. While studying these lights, we will learn how to use the spectroscope and prepare for the time to see the Marfa Lights in Texas. By drawing out sketches, taking pictures, and recording our results, we will try to match our ideas with the actual lights we will see in Marfa. If we match the lights, our experiment will be a success. The final step would be to determine what is causing the lights. V. Procedure for testing in Lexington, IL 1. Remove the telescope from the box and mount it on the tripod. 2. Screw on eyepiece-holder/diagonal prism. 3. Screw on spectroscope lens to the bottom of the eyepiece. 4. Slide eyepiece into eyepiece holder. (Don't let eyepiece rest on the mirror.) 5. Tighten knob on eyepiece holder. 6. Unlock the R.A. lock. (Right ascension lock) 7. Find the light source using the view finder. (Center on the cross hairs. Should be a mile away from you.) 8. Lock the R.A. lock to insure stability. 9. Focus in on the brightest light source using the focus knob and R.A. knob if needed. 10. Once you have the lights in sight, record your results. (We will either draw our results or use the camera to photograph our results.) 11. Repeat this for each of the different light sources. VI. Procedure for Marfa, Texas 1. You will set up the telescope and spectroscope just like you did above. 2. Aim the telescope in the direction of the Marfa Lights and focus in on one of them. 3. Record the results in the same way as directed above. 4. Repeat as necessary. VII. Experiment 2 1. Take a picture of light source with slide film 2. Project slide 3. Look at it with spectroscope 1. See if we can analyze spectrum VIII. Analyze 1. What type of light does the Marfa Lights most resemble?

Conclusion: The light most likely resembles headlights based on our evaluations and photographs of their spectra.

They conducted a number of other experiments, but did not post their results.

Conclusions

In all, our trip to Marfa, Texas was a huge success scientifically as well as it was sociaily. We scientifically proved with a number of experiments that the Marfa LIghts we saw were indeed only headlights coming from a distant road in the mountains. We were told, however, that the "Marfa Lights" we saw were not the only recorded type of them seen. It is said that there have been mysterious lights seen in the horizon to the left of the "headlights" that are unexplainable. We, unfortunately were not lucky enough to witness these. If you look through our experiments, you will see that some did not work the way they were planned, while others surpassed the expectations we had of them. Hopefully we have brought enough evidence back with us to prove to you our theory without you having to be there with us. To get the full experience you must see them in person, though. We encourage you to visit these wonders if you are ever in the area! They truely are unexplainable at first sight.