Sure! Here is a partial list:
A recently discovered Comet was observed to fragment into dozens of pieces and, one by one, impact Jupiter. It was one of the most intensely watched events in recent astronomical history. The impacts created dramatic scars on Jupiter which took a year to 'heal'. There is a nice set of pictures from the Hubble Space Telescope, one of which I reproduce above, showing the dark spots left from several of the comet fragments stirring up the jovian atmosphere. Also, the Jet Propulsion Laboratory has their own SL9 Home Page. if you want more information.
14 years ago, the Voyager 1 spacecraft detected several new moons near the ring system of Saturn. When the rings were edge on to the Earth, the Hubble Space Telescope could not find one of these, but found another moonlet in a brand new orbit which was not seen at the time of Voyager. The presumption is that one of the moonlets was knocked into this new orbit from some collision or encounter during the last 14 years.
The Maunder Mininum is a severe reduction in sunspots discovered by E.W.Maunder in 1890 following a careful study of sunspot frequencies. Even though plenty of people were studying the Sun after the discovery of the telescope, there were only scattered reports of a few sunspots actually seen. Astronomers believe that sunspots and sunspot cycles are a rather recent phenomenon on the Sun that began at the end of the Maunder Mininum and continues today. The Maunder Minimum also corresponds to a period of extreme winters called the 'Little Ice Age' in Europe.
The Great Martian Dust Storm greeted the Viking Orbiter in 1976 and grew to engulf the entire planet in a matter of a few weeks. Since then, although astronomers have seen the orbital conditions repeat many times, there has been no trace of major dust storm activity on Mars. No one really knows why dust storms happen on Mars, and the Great Storm seems to have ended for now a rather long string of such phenomena which have been observed for decades with some regularity. Go to the Hubble Space Telescope website for a 'weather report' from Mars.
In 1908, something streaked through the atmosphere over Tunguska and detonated in the atmosphere. All the trees within 20 miles of the impact area were flattened. Astronomers think it was a comet nucleus since no traces of the object have been found in the soil around the site. The region wasn't studied until decades later since this happened during a time of great turmoil in what was then called the Soviet Union.
English monks may have witnessed the impact of an object with the Moon that created what we now see as the rayed, young crater Bruno.
Copyright 1997 Dr. Sten Odenwald
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