Hubble space telescope visible imaging of Jupiter during the Comet crash

Abstract

In July 1994, the fragments of Comet Shoemaker-Levy 9 plunged into Jupiter. We present preliminary results from analysis of the Hubble Space Telescope (HST) imaging observations of Jupiter obtained before, during, and after the impacts. We discuss observations of observed phenomena ranging from plumes to waves to atmospheric evolution. We report positions of all detected impact sites (we could not locate F, P2, T, U, and V). By comparing predicted and observed impact longitudes, we estimate the actual impact time. On average, impacts occurred about 8 minutes later than predicted, although this varied from on time to more than 15 minutes late. We also present an assessment of the relative size of the disturbance for each event. HST images showed the development of several of the erupting plumes (A, E, G, and W) over a period of about 20 minutes. In three cases (A, G, and W), we may have detected the incoming bolide, although alternative explanations for pre-plume flashes are possible. For fragments E, G, and W, we detected the 10 to 15 km/sec. A fascinating and unexpected feature of the impact plumes is that they all appear to reach the same height (about 3300 km) regardless of the size of the impactor that generated them. This point greatly confounded the impact modelers, who planned to use the plume heights to estimate the diameter of the impacting comet fragments.