Dust pathfinding with Galaxy Zoo
Now that spring classes are over, I’m catching up with lots of things. These include making color-composite images from our latest observations at the WIYN 3.5-meter telescope in Arizona done to follow up overlapping-galaxy pairs from the Forum. Here are three samples, showing how much more detail we can see with long exposures one the objects have been found from the SDSS data. In SDSS J215311.30-073533.5, the WIYN images show just the kind of thing we’re looking for – dust in spiral arms silhouetted against the light of the background galaxy. First here is the SDSS image, then the WIYN picture below it.
This pair, SDSS J231444.84+063821.3, shows a very deep overlap, with spiral structure that only appears as a blue patch on the SDSS.
And finally, for a change, we see UGC 1689 (also known as SDSS J021200.15+140059.1), where there are many background galaxies but all so distant that they look much smaller. Here we can look for smaller patches or arms of dust in the outer part of the galaxy.
We’re working away to measure the amount dust absorption in these and the 25 or so other pairs from that observing session. Mostly that means that Anna is spending her days doing the calculations trying to make a thesis deadline in August. I send the data along after processing and otherwise try to stay out of the way.