Public Lab Wiki documentation



Getting started with Spectral Challenge

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Interested in Spectral Challenge? Not sure how to get started? Browse the ideas below, then pick and choose some steps that will work for you and your community! Believe it or not, you can do spectral analysis without having prior knowledge or training. Simply being observant and trying to figure out what is going on will get you far. Posting your spectral results to spectralworkbench.org will connect your efforts to a community of researchers who can help. For full description, see spectralchallenge.org

Setting up your online notebook

Join this website to use the "online logbook" for keeping track of your process under your username (for example, here's my my profile page, scroll down to see all my research notes). This login will also work for the web software you will eventually use: spectralworkbench.org

Figuring out what you are interested in

Ask yourself what environmental contaminants you're interested in. What have you heard about as a local issue in your nearest garden, river, lake, etc? For instance, lead, crude oil, PAH - polyaromatic hydrocarbons, e. coli bacteria, or something else.

Consider whether these contaminants are elements, molecules, biologicals, other? A rule of thumb is that the simpler the chemical structure, the simpler the spectrum. Since biologicals are complex and change over time, perhaps it's better to start with elements and molecules. When you decide what you want to focus on, make your first research note describing the focus of your research. Tag the note spectralchallenge.

Getting more folks involved / organizing a team

Ask your friends if they have ever wondered how they could tell what chemicals were present in their water or soil. Hold a meeting to bring folks to together to brainstorm and see if shared interests emerge. Come up with a name for your group, puns intended :). You can list your team here: http://publiclab.org/wiki/spectral-challenge-teams and also use your group's name as another tag for your research notes.

Getting ready with sample containers

Get ahold of some clean glass containers, perhaps even order some cheap sterile glass containers from a science supply website to avoid soap residue from handwashed tupperware ;). A container with flat sides and bottom will make it easier to shine light through. Perhaps you can encourage a friend to take care of this step?

Collecting known reference samples

Think about where you can get a sample of the contaminant(s) you are interested in:

  • If you are thinking about fertilizer runoff from nearby farms, consider going to a farm supply store and buying a small quantity of common fertilizer.
  • If you are concerned that fuel from a local waterfront fuel depot is spilling into your waterways, you could go to the depot and ask the staff for a small sample.
  • If you suspect lead in your soil, go to the fishing section of a local store and buy a lead fishing weight.

If you are working with a group of people, this is a perfect task to share. Each person can go out and get one reference sample. Once you have reference samples, post another research note about your process, again, tagging it "spectralchallenge".

Sample preparation / method of analysis

There are two main things to think about in sample preparation.

  • The first has to do with whether the sample is in soil or other opaque material that light will not be able to pass through. In that case, you may have to soak your sample in something like mineral oil, see this research note for one example.
  • The second has to do with what kind of analysis can reveal the element or molecule you are interested in, for example, "heavy metals" are not identifiable by their spectrum alone under plain visible light. You might have to place your sample into a squirt bottle so that the mist can be exposed to high temperatures AKA fire :). The wiki page spectral analysis is where different techniques are being collected.

Sample preparation and method of analysis are areas where there is lots of progress yet to be made (read: winning Spectral Challenge Phase 1!) Work out how you want to prepare your sample, emailing the list to ask questions etc. Asking questions does NOT disqualify you! On the contrary, it gains visibility for your efforts which is a big part of "doing research in public".

Setting up your work station

A desk or table surface will be helpful. For instance, you may want your sample containers at hand. Have you built or purchased a spectrometer yet? This page has links to both the store and the lists of parts and instructions: http://publiclab.org/wiki/spectrometer. The spectrometer will need to connect to a computer via USB cord, and that computer should be online. Check out this really great page that covers the first things to do with your spectrometer: http://publiclab.org/wiki/spectral-workbench-usage.

Connecting to the spectralworkbench community

In spectralworkbench, you can create sets to compare two or more spectra, which is helpful for explaining your results. See this set for a simple example of this, both in the graph and in the accompanying sentence: https://spectralworkbench.org/sets/show/24

Pulling your Spectral Challenge entry together

Once you have chosen your focus, collected reference samples, prepared them for spectral analysis, captured their spectra, and created a set to explain your results, post one more research note writing up what you have learned and other helpful tips. Tag it "spectralchallenge"! That's it - you did it!

Inspirational quote!

"If you want to find the secrets of the universe, think in terms of energy, frequency and vibration." - Nikola Tesla