The temporal evolution of the July 2009 Jupiter impact cloud

Vertical cloud structure of the 2009 Jupiter impact based on HST/WFC3 observations

“…Compared to what was reported after the SL9 impact (West et al, 1995), the 2009 IC particles seemed to be about 1 lm in size Baines et al, 2012) or from 4 (West et al, 1995) to almost 7 times bigger than the SL9 dark particles. Such differences could be due to the possibly different nature of the impact bodies, and/or to the fact that the 1994 collision was caused by multiple impacts of different sizes, while the 2009 event was most likely a single, intermediate-sized impact.…”

“…There are basically four mechanisms for the IC to relax into the undisturbed atmosphere: (1) horizontal transport by the zonal winds, meridional circulation, and local motions induced by the impact; (2) vertical transport by sedimentation (gravity dominated) or diffusion (dominated by compositional gradients); (3) modification of the IC particles by photochemistry, microphysics and other processes; and (4) a combination of any of the above. The study of the horizontal movements clearly favors the first option (Sánchez-Lavega et al, 2011), while sedimentation rates even for the biggest possible particles are too slow to account for the observed variation of the morphology (Baines et al, 2012). On the other hand, there is also an important spectral component in the brightness of the IC.…”

“…The impact of an object with Jupiter on 2009 July 19 Hammel et al, 2010) caused a disturbance on the atmosphere of the planet which lasted for some weeks (Sánchez-Lavega et al, 2011;Baines et al, 2012). This rare event was imaged by a number of facilities all around the world at visible and infrared wavelengths (e.g., de Pater et al, 2010;Fletcher et al, 2011) including the Hubble Space Telescope with the recently installed camera WFC3 .…”

“…The latter is still open, particularly regarding the temporal evolution of the IC generated by the event. Recently, infrared observations have shown how the IC dissipated into the surrounding atmosphere (Baines et al, 2012) but the high-quality HST WFC3 observations were still to be analyzed in detail.…”

Impact flux on Jupiter: From superbolides to large-scale collisions

“…First, impacts such as the SL9 and the 2009 impacts, allow us to directly study the consequences of a large impact in a planetary atmosphere (Hammel et al 2010;de Pater et al 2010;Sánchez-Lavega et al 2011;Pérez-Hoyos et al 2012;Fletcher et al 2010Fletcher et al , 2011Baines et al 2013). Second, small objects producing bolides give us insight into the physics of atmospheric impacts at much higher velocities (∼60 km s −1 ) than in similar objects colliding with the Earth (11−20 km s −1 ).…”