Target Jupiter


Most astronomers--but surprisingly few of us regular folks--realize that our solar system, with its average-sized star and nine planets, is still in a state of flux. Far from being stable, the solar system is still sorting itself out, sweeping up the chaotic debris of comets and asteroids left over from its earliest beginnings. Recently, two astronomers--Brian Marsden, of the Harvard-Smithsonian Center for Astrophysics, and Paul Chodas, of California's Jet Propulsion Laboratory--announced the first predicted collision of such cosmic leftovers with a planet. The recently discovered Comet Shoemaker-Levy is on a beeline course for Jupiter and is expected to plow into the planet next July. At the most recent meeting of the American Astronomical Society, in Berkeley, California, NASA astronomers Chris Chyba and Kevin Zahnle described the predicted event in some detail: the resultant explosion will be equivalent to an explosion of 200 million megatons of TNT--more powerful than the simultaneous detonation of all the world's nuclear weapons.

The catastrophe that Chyba and Zahnle described may rival the collision between the earth and a comet 65 million years ago, an event which many believe killed off much of the life on our planet, including the dinosaurs. Zahnle explains that because of the comet's unusual nature, the event on Jupiter could cause the giant gaseous planet to flare up repeatedly to twenty-five times its usual brightness over the course of a few hours. Comet Shoemaker-Levy has been captured by Jupiter's tremendous gravitational field and is now revolving in an orbit around the planet. On July 8, 1992, Shoemaker-Levy passed 30,000 miles above Jupiter's cloud tops, within what astronomers call the Roche Limit: the critical distance from the center of a planet at which tidal forces are sufficient to disrupt and tear apart a satellite (or, in this case, a comet). As a result of its close approach, Shoemaker-Levy was ripped up into a train of smaller pieces-like "pearls on a string" as one astronomer described it. The best orbital computations available at press time suggest that a part or all of the cometary debris will collide with Jupiter at speeds of 40 miles per second sometime between July 23 and July 27, 1994. Donald Yeomans, an orbit specialist at the Jet Propulsion Laboratory, has calculated a probability of 64 percent that the center of the comet train will collide with Jupiter. In the case of a glancing strike, the pieces on the trailing end of the comet train might survive to escape Jupiter's gravity and go into a more typical orbit around the sun.

Comet Shoemaker-Levy, once a twelve-mile-wide chunk of ice and rock, was discovered last March 24 by the comet-hunting team of Carolyn and Eugene Shoemaker, David Levy, and Philippe Bendjoya with the 18-inch telescope on Palomar Mountain. When James Scotti saw the comet with the University of Arizona's Spacewatch Telescope on March 26, he said it looked more like a "comet stream." When Jane Luu and David Jewitt imaged it with a camera mounted on the 86-inch telescope on Mauna Kea in Hawaii, they were amazed to discover seventeen separate cometary nuclei. That figure is now at twenty-one, and the largest of these--at this writing--imaged on July 1, may be six miles across.

To the immense disappointment of earthly sky watchers, this entire catastrophic event will occur on the night side of Jupiter, which faces away from us. But because Jupiter rotates on its axis once every ten hours, we should be able to see the effects of the devastation a few hours after it occurs. And the reflected light of the explosion on Jupiter's nearest satellites may be visible with small telescopes--perhaps even with binoculars.

As each piece of cometary material plunges into Jupiter's thick atmosphere, it should break into rubble and then, 100 to 200 miles down, be destroyed by intense atmospheric resistance. This destruction will cause an enormous release of energy in the upper layers of the planet.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Target Jupiter
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.