Banneker Institute: Week #2

Two weeks ago, I had no idea how much work had to be done with light curve data before you could actually start fitting the light curve. I guess I never really thought much about what needed to be done, but naive little me probably thought that data came to us ready to be plotted, and all that was left to do was fit.  Boy was I wrong!

If you've been following this blog, you know a bit about what I've had to do with my data over the last couple of weeks. If you haven't, you can read those old posts now, or you can keep reading this one for a brief summary (but if you don't go back, you'll miss most of the pretty plots I've been making).

Here's what I've done so far:

1. Fold the data $\rightarrow$  This involves stacking all of a planet's transits on top of each other.  This makes the transits easier to see (just to check that Kepler isn't going crazy and you actually do have transits in your data) and allows you to separate data points that are in a transit from those that are out of one, which leads to...
2. Remove Outliers $\rightarrow$ Only remove points from a list of data points that occur oustside of any transit for any planet. The $\sigma$ value (how many $\sigma$s away from the mean you want to start removing data) chosen is that which, probabilistically, would only remove one good data point.  
3. Separate Planets $\rightarrow$  Make individual files for each planet excluding points that occur in any other planet's transits. The motivation behind this step is probably the least intuitive.  This step is necessary because (a) working with individual files for each planet is easier in the long run and (b) this eliminates the -- incredibly small -- chance that two planets could have overlapping transits. 

But now that that's done, I can (a) be super proud of myself and (b) move on to actually fitting the light curves for each of the planets in my system. I don't know what this entails, exactly, but I'll let you know when I do.

Today's post was pretty short.  I'm sorry about that. But to make it up to you, I'll leave you with a riddle.

You have 12 cubes, and they all look and feel identical, except for one, which is slightly heavier or lighter than the others. Using a mechanical balance only three times, how do you figure out which cube is different and whether it is heavier or lighter??

Feel free to comment below or email me (momctier@gmail.com) with your answers, but I'll be posting the solution next week.