I have found my notes of the observation of the impact of comet Shoemaker-Levy 9 on Jupiter in July 1994.
I remember the emotion caused by the discovery that a shattered comet was going to impact on Jupiter in July 1994. This comet was formally called D/1993 F2, although it is better known as Shoemaker-Levy 9 (the ninth found by its discoverers) or, simply, SL9. The comet followed an unstable orbit around the giant planet and was broken into a dozen of fragments, or more, due to tidal forces. It was later seen that those fragments were going to fall on Jupiter and it was calculated when they were going to do so, one by one.
The expectation was amazing. Galileo space probe, by then on its journey to Jupiter, was the only human observatory that directly catched the impacts, because they happened slightly beyond the planetary limb from the point of view of the Earth. Even though, a global observational campaign was undertaken from our world, including even the Hubble Space Telescope.
By then I was a graduate student at the Department of Astronomy and Meteorology of the University of Barcelona, and I could not resist the temptation to go up to the flat roof of the faculty building to install one of the Celestron 8 telescopes that we had for practical work with the students. I did so on July the 21st 1994, at 22:45 official time (20:45 UT) and I took some notes on a paper that has been almost twenty years inside a book.
My first diagram shows the planet and the configuration of the Galilean moons around. It is reliefing to see that modern planetarium programs, such as Stellarium, reproduce so well what I draw then.
Another sketch, much more detailed, shows two dark impact marks in the Southern hemisphere of Jupiter. An arrow with a question mark seems to indicate that I thought that I may have seen something else at the West limb of the planet.
