A Prediction About Saturn’s Rings
One of the cool things I’ve done with data from Cassini is analyze self-gravity wakes in Saturn’s rings. These are long, finger-likeshaped clumps of particles in the rings (a few tens of meters across and perhaps 100 or more meters long) that are the result of the particles running into each other and trying to accrete through gravity, but getting pulled apart by tides from Saturn. We published a paper earlier this year (Geophysical Research Letters, Vol. 33, L07201, doi:10.1029/2005GL025163 for those interested in the gory details) using our first measurements of Saturn’s A ring to derive the size and shape of the clumps in the ring. I have used that model to predict what we will see with our next measurement on July 25, 2006. You can see the prediction (purple curve) here. The other curves on the plot show the range of values from different measurements to date. Once I get the data I will post a comparison of the observation with the prediction. This is a fun opportunity to see the scientific method in action:
1. Observations by Cassini led to a theorymodel (the theory was proposed more than 30 years ago and has been developed by a number of researchers since then; we developed a particular mathematical model based on that theory and applied it to Cassini data;) of self-gravity wakes;
2. Application of that theorymodel to the data produced a prediction for a future observation;
3. July 25 comes the test of the theorymodel which will either confirm or refute the theory.
My guess is that there will be good, but not perfect, agreement between prediction and observation. This would then lead to some modification of the self-gravity wake parameters that I have previously calculated. We will be back at step 1 with an improved model of the ring. Check out the prediction and check back in a couple of weeks to see how well I did.