Jupiter and Shoemaker-Levy 9. What happened? Teacher resources
Name: Gerry A Adams and Charlie H Bell
Guten Tag from Germany.
My question concerns the Jupiter-comet event that will take place in July.
1. What is the name of the comet and what is it?
2. What are the expected results of this collision?
3. What is the best guess as to when it will happen?
4. Do you know of any good resources for teaching astronomy to junior high
Tschuss Gerry Adams
The comet's name is P/Shoemaker-Levy 9 (I do not know what the "P" means).
At least 21 fragments of this comet will collide with Jupiter during July
16-22. Current best estimate for the first major fragment's impact is 19:5-
3:40 Universal Time (with an uncertainty of 8.4 minutes). (This figure was
issued by P. W. Chodas, D. K. Yeomans and Z. Sekanina of JPL/Caltech and P.
D. Nicholson of Cornell, as of July 5). No one is certain what the effects
will be because the sizes of the fragments are not known for certain
(although the 11 largest are believed to be 2-4 km in diameter), and it is
not known to what extent each fragment will hold together once it plows into
Jupiter's atmosphere. There are several possible scenarios; the fragments
may disintegrate in the upper atmosphere, or they may manage to penetrate to
some depth in the atmosphere. There may be flashes bright enough to
momentarily brighten one or more of Jupiter's moons. If the fragments
penetrate deeply enough, they may cause material from Jupiter's lower
atmosphere to erupt through the cloud tops (which are all we can normally
see of Jupiter). None of the collisions will be directly observable from
Earth, but the spacecraft Galileo will be able to "see" the impacts, and
with luck there will be some visible effect as the impact sites rotate into
There is lots of astronomy stuff (text and images) available in the World
Wide Web (WWW); you need a browser (like Mosaic) to navigate through it all.
Update--I obtained this info via anonymous ftp from tamsun.tamu.edu. The
following is excerpted from material in the file comet.faq which resides in
the /pub/comet directory. There are a number of files there which may be of
interest, including some images from last March of the Shoemaker-Levy frag-
ments (in GIF and Postscript formats). Be warned--the image files are big
(~ half a Meg for the Postscript (.ps) files). There is a bunch more info
in comet.faq which I have not quoted. "The shattered comet Shoemaker-Levy 9
(1993e) is expected to collide with Jupiter over a 5.6 day period in July
1994. The first of 21 comet fragments is expected to hit Jupiter on July
16, 1994 and the last on July 22, 1994. All components of the comet will
hit on the dark far side of Jupiter, out of sight from Earth. "Although
[the expected points of impact] are still all on the far side as viewed from
the Earth, they are now only 5-9 degrees behind the limb. About 12 - 24
minutes after each hit, the impact points will rotate into view as seen from
Earth. Anything ejected higher than 500-1000 km above the cloud tops during
the impacts will be visible from Earth."
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Update: June 2012