I’M LEARNING SPECTROSOPY

I haven’t written anything in quite some time and I apologize, but I have been very busy. Part of me being busy is the fact that I have been working on putting together a spectroscopy rig. I had most of the pieces laying around and just had to add a bit to make it work.

WHAT IS SPECTROSCOPY?

Spectroscopy is the process of taking light (starlight, comet light, planet light, supernova light, etc.) and spreading it into the colors of the rainbow using a prism or diffraction grating. With the analysis of the intensity of the light at each point on that spectrum, the intensity will vary. Some points will really stand out, and others will be diminished considerably. Analysis of all these points is like a fingerprint of the star and its makeup.

Jospeh Fraunhofer first broke light into the colors of the rainbow with a diffraction grating and discovered that there were dark lines visible at areas of this spectrum. These dark lines were linked later to being the result of various elements present that were blocking the light, creating these absorption lines. Each of these lines corresponded to a specific wavelength, allowing the identification of things like hydrogen, helium, carbon, iron, magnesium and so on. Depending on if the element was in front blocking the light (absorption lines) or in the forefront emitting light (emission lines), determined the makeup and position of the elements in the spectrum of light.

This is the basis of spectroscopy, analyzing light to learn more about the object. Think of it as chemical forensics.

HOW DOES IT WORK

I have purchased two items from Tom Field, creator of the RSpec software.

One of the items is the SA-100 diffraction grating, which is a 1.25-inch threaded grating that goes in the light path and breaks the light into a spectrum before landing on the cameras sensor where it is captured and saved.

The second items is the RSpec software, which is a Windows application that takes the image you captured with your camera and graphs it, and allows you to calibrate it to a specific wavelength using a type A star, as well as perform analysis on it using reference spectra to calibrate for your camera, superimpose specific Balmer lines for various elements on the graph to see if it is present or not. You will know what is present by using these index points to see if there are peaks associated with it, or dips associated with it. Once again, peaks are emission lines, and dips are absorption lines.

WHAT CAN I DO WITH THIS?

With the ability to analyze light from space, you can do things like determine star temperature, star chemistry, whether the objects are coming at or moving away from us. You can spot the chemistry of a planet’s atmosphere such as the methane on the gas giants. You can look at the emission of light from a comet for its makeup, and so on.

I am going to enjoy doing this. It is an opportunity to gain knowledge about the universe and use the tools that professional scientists are using. The equipment we have today may not be as good as what professionals are using, but it is superior to what they were using just a brief time ago.

If you are interested in learning more, visit Tom’s website RSpec / Real-time Spectroscopy