Tropical Astronomy

So funny story... I've been in Puerto Rico for the past week and have been doing astronomy and I haven't blogged about it.  Which is sad and silly and is a situation I need to rectify.

However, to be perfectly honest, I'm not really sure what to say about everything.  I am working as a summer student at the Arecibo Observatory analyzing the recombination curves of neutral hydrogen transfer to determine and quantify the degree of asymmetry in galaxies.   In deep space (it doesn't happen with significant frequency in dense areas like our atmosphere) stray electrons find stray protons and form atoms.  Except they don't form atoms the way we see them on Earth.  On Earth, hydrogen is one electron around one proton in that atom's lowest or first energy level.  In SPACE (please imagine that in a ridiculously dramatic voice) an electron will find a proton and settle into it's 500th energy level and cascade down to a more stable energy level.  This emits radio waves which we can see with radio telescopes.  This only happens in deep space because out there there is far less interference so electrons and protons can form atoms with huge radii.  By detecting these transitions we can determine the density of nebulous objects because we can figure out how much hydrogen is there.  This process takes a long time but it happens pretty often, so it's really useful.  Depending on the orientation of the galaxy, we can determine how it's spinning relative to our plane of observation.  Do me a favor, hold a piece of paper out in front of you.  Now turn it so that you're looking at the thin edge.  If the galaxy is spinning in that orientation, we see a double horned profile (the one on the left).  Now flip it so that you can see the plane of the paper.  If the galaxy is spinning in that orientation, we see a Gaussian profile (the one on the right).  Normal galaxies produce a mostly symmetrical profile whereas what I will call funky galaxies produce an asymmetrical profile.  Galaxies can be funky because of their activity level (galaxies that are forming a lot of new stars will be asymmetrical), because they have an energy producing black hole, because they're interacting with another galaxy, or something.  Galaxies are still kind of a mystery to science.  In any event tracking neutral hydrogen transfer can help you figure out how far away the galaxy is, the total amount of neutral hydrogen in said galaxy, and how fast the galaxy is rotating.  It's a very useful tool.

For my work, I've been writing a program in IDL to quantify the degree of asymmetry based on figureing out to what degree the graph of the curve and the inverse graph of the curve match up.  It looks like this:

I think you can click to enlarge.

What you see on the right is a graph of the degree of asymmetry.  The program on the left takes the relative max of that graph and divides it by the root mean square of the noise on one side to determine the degree of asymmetry of that particular galaxy.  There are better ways to do this calculation (for example you can write a program that properly quantifies the mass of the galaxy on both halves of the graph which is much more accurate) but this is a good start.  When you run the program (what you see above is just the text of the program itself), it looks like this:

In case you're wondering, my background is a Schrödinger's Cat joke.

So that's going to be my life for the next two weeks.  I'm starting a new project soon that I think will take what I've been working on a little further.  I'll be sure to keep you updated, unlike this past week.