in a dramatic proof that solar coronal mass ejection (CME) events affect even the outermost portions of the Solar System, scientists have traced an interplanetary shock from the Sun to Earth to Jupiter to Saturn.
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They report the discovery of a strong transient polar emission on Saturn, tentatively attributed to the passage of an interplanetary shock. The shock-triggered events were first seen here on Earth, where auroral storms were recorded. Next, auroral activity on Jupiter was seen to be strongly enhanced. Finally, the unusual polar emission on Saturn was noted. This sequence of events establishes that shocks retain their ability to trigger planetary auroral activity throughout the Solar System.
In their 1992 science fiction book Flare, Roger Zelazny and Thomas T. Thomas chronicle the effects of a huge solar flare as it wreaks havoc across the inhabited worlds and space stations of the solar system. The effects of this event on the orbiting EverRest Cryotorium were described as follows:
The EverRest Cryotorium orbited low over the Earth ... forgotten by a handful of individuals ... some who worked daily in the NASA Department of Decaying Orbital Artifacts - the "Trash Squad."However, with the unaccustomed surge of electromagnetic noise that was echoing throughout the inner solar system, and with the ensuing panic as normmaly talkative human beings discovered that their multiplex communications system was effectively blanked out, no one happened to be looking at the sky.
Unappreciated by these people, for the past twenty minutes the ionosphere 500 kilometers uner the EverRest's keel had been absorbing huge blasts of intense radiation from the solar flare.
The air density at such a height above the Earth's surface is quite thin: ranging from two millionths down to five billionths of a gram per cubic meter... the molecular fragments remain at their current altitude because the collective collisions of their gas pressure, energized by the sun's radiation, propel them upwards against the pull of gravity... heat the gas and you increase its pressure. Without confining walls or a steel tank to contain it, the volume of gas expands.
...the continuous influx of high-energy radiation had trippled the ambient temperature of the lower ionosphere. The resulting swell in the volume of gas pushed upward, increasing the density of material in EverRest's immediate vicinity by about fifty times.
The effect was immediate.
The orbiting hull reacted as if it had hit a wall.
(Read more from Flare)
Solar flares occur when magnetic energy built up in the solar photosphere is suddenly released. Radiation across the entire electromagnetic spectrum is released; the energy released can equal that of a million 100 megaton hydrogen bombs exploding at the same time. The first flare recorded occurred in 1859. A solar flare in 1989 blacked out all of Quebec, Canada. Solar flares in 1998 knocked out the Galaxy 4 satellite, causing eighty percent of the pagers in North America to fall silent.
The sun's corona is highest region of the solar atmosphere; it can be seen during a total eclipse as a large halo of white, glowing gas extending several solar radii from the solar disk. A special telescope called a coronagraph that artificially eclipses the sun's disk is used to study the solar corona on a regular basis. A coronal mass ejection (CME) can occur without a flare, although they are often associated. A CME can carry up to 10 billion tons of electrified gas traveling at speeds of up to 2,000 kilometers per second. Fortunately, our planet's magnetic field serves as shield against these storms.
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The results were published in a letter to the journal nature by Renee Prange, Laurent Pallier and Regis Courtin (LESIA, Observatoire de Paris); Kenneth C. Hansen (Department of Atmospheric, Oceanic and Space Sciences, University of Michigan); Russ Howard and Angelos Vourlidas (Naval Research Laboratory); and Chris Parkinson (California Institute of Technology, JPL and the NASA Astrobiology Institute). Read An interplanetary shock traced by planetary auroral storms from the Sun to Saturn.
