mountain profile Institute for Astronomy University of Hawaii

Research Experience for Undergrads (REU) at IfA 2004 (Ellis presentation)

Maintained by HAF

Manipulating Schwassmann-Wachmann 1

Chase Ellis

Mentor: Yanga Fernández

Most of my summer has been dedicated in some way, shape, or form to the odd comet P/Schwassmann-Wachmann 1. SW-1 sets itself aside from your common comet with its large nearly circular orbit (R ~ 6 AU, e ~ 0.004) and the high amount of activity taking place at the nucleus. SW-1 has also been known to experience large "outbursts" in a non-periodic fashion, allowing the comet's brightness to increase by 1–2 magnitudes within a week or so. During these times of "outburst" lots of structure (usually in the form of jets) can be seen in the comet's coma, making it an ideal comet to study the nature of these jets. The only problem is that we must find these jets in the midst of SW-1's bright dust coma.

Eventually the jets found on SW-1 will be folded into a rotational model for the comet, but for now we must find out where the jets are and how they are changing as time goes on. In order to find the jets we applied 6 different image manipulating techniques, commonly used for studying coma, to our images of SW-1. The use of all 6 techniques on each image is important so that artifacts induced by the manipulations are not mistaken for jets. Overall these image manipulations did a good job of increasing the definition of SW-1's jets, allowing us to pinpoint their location radially over time. At this time in the project it is hard to say much result-wise about these jets and SW-1's rotation. But all in all, two rotating jets in "outburst" can continually be seen projected from SW-1 in opposite directions throughout the summer 2002 data. Whether these two jets' "outbursts" or orientations are in some way connected we still aren't sure. With more time we will be able to model the rotation of SW-1 with the help of the data extrapolated from this summer's project.