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Credit: NASA ,ESA , P. Feldman (Johns Hopkins University) and H. Weaver (Johns Hopkins University Applied Physics Laboratory)

Caption: The Hubble Space Telescope captured this image of a flare emerging from comet Tempel 1 on June 14.
Such outbursts are only one of many features of comets that astronomers “don’t fully understand”.


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Jun 30, 2005
Deep Impact

The scientific media have vigorously promoted the coming "Deep Impact" encounter with comet Tempel 1.  But comet experts are not going to see what they've expected, say theorists of the "electric comet".

A potential turning point in the exploration of space will occur on July 4.  That's when comet Tempel 1 will be near perihelion (its closest approach to the Sun). The Deep Impact spacecraft, launched on January 12, 2005 and now rapidly approaching the comet, will fire an 800-pound copper projectile into the comet's nucleus.

NASA scientists expect the probe to break through one of the barriers to scientific understanding of comets. The mysteriously blackened surface of comet nuclei—darker than coal—have been so drastically changed by their recent history that the observed features yield little if any reliable information about what lies underneath. But by penetrating beneath the nucleus' surface, the exploding projectile from the Deep Impact probe will eject into space large volumes of underlying material. Instruments on board the probe will observe, measure, and analyze it.  According to NASA scientists, the released material will provide a sample of the primordial water, gas and dust from which the Sun, planets, moons, and other bodies in the solar system formed.

How do they know this? It is a theoretical guess based on a theory that from the beginning has been contradicted by observations. According to proponents of the Electric Universe, such as Wallace Thornhill and Don Scott, comets have the potential to challenge the underpinnings of space science today. According to the cosmic electricians, everything we have learned about comets challenges the old paradigm:

  • the premature discharging of comets beyond the orbit of Jupiter, where known icy bodies do not sublimate under solar radiation.
  • the repeated "surprise" of water content well below expectations—or no evidence of surface water at all.
  • the unexplained outbursts of dust, some even beyond the orbit of Saturn.
  • the narrow energetic jets from comet nuclei, defying the expectations for sublimating ices.
  • the "shocking" breakup or explosion of comet nuclei as they race toward the Sun.
  • the high energy X-rays from comets.
  • the sharply sculpted surfaces of comet nuclei (quite the opposite of the expected softening of features in melting chunks of ice).
  • the coherent filaments and "knots" of comet tails, often extending for many millions of miles without dissipating.
  • the mysterious "anti-tails" or "anomalous tails" of various comets, projecting toward the Sun, not away from it.

These features are expected in the Electric Universe model. In that model, cometary intruders are highly negatively charged in relation to the Sun. The Sun is the positively charged body—the anode—at the center of an electric field reaching past the planets to the remote "heliopause." The heliopause is the insulating sheath or electrical boundary that mediates between the electric potential of the Sun and that of interstellar space. As a comet approaches the Sun from more remote, negative regions, it grows increasingly out of balance with its surroundings and begins to discharge electrically. All the surprising and anomalous observations in the previous list are typical characteristics of electrical discharges in plasma.

Furthermore, the Electric Universe rejects the traditional story of the formation of all the bodies of the solar system at one early epoch. In the electrical model, comets and asteroids originate from planets in episodes of formation. So there is no expectation that comets will reveal a consistent or primordial composition. The variability in cometary material already discovered supports this view. 

Deep Impact will thus provide another important test of the electric comet theory. Therefore, in our Picture of the Day on July 4, we shall present a review of the theoretical issues, along with predictions, prior to the Deep Impact event.


David Talbott, Wallace Thornhill
Amy Acheson
  CONTRIBUTING EDITORS: Mel Acheson, Michael Armstrong, Dwardu Cardona,
Ev Cochrane, C.J. Ransom, Don Scott, Rens van der Sluijs, Ian Tresman
  WEBMASTER: Michael Armstrong

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