Coronal Mass Ejections

(updated 2-23-97)

fig 6

This is a quote from The Los Alamos research projects, that explains just a few basics of CME's:

"CMEs are clouds of hot (1-2 million degrees) ["magnetic plasma"] gases ejected from the Sun at extremely high speeds (from several hundreds to 2000 km per second). After acceleration at the Sun, they travel through interplanetary space and reach Earth in 2.5 to 5 days. When they reach the Earth, CMEs cause disturbances in the magnetosphere, which trigger auroras, make magnetic navigation at high latitudes difficult, and sometimes cause current spikes in high-voltage power lines, resulting in power outages and occasionally in destruction of power equipment. They also can damage or destroy Earth-orbiting satellites."

This quote from a CNN report on a CME that actually hit the Earth on January 10th of 1997:
"Solar radiation might have killed satellite (CNN) -- NASA scientists say a wave of solar radiation called a Coronal Mass Ejection may have knocked out the Telstar 401 communications satellite last week. The AT&T satellite went dark on Saturday, January 11, leaving television networks ABC, FOX and PBS scrambling to find other ways to distribute their broadcasts. NASA now says other satellites, including military satellites transmitting classified data, may have been disrupted as well. The satellite failures coincided with a strong explosion of hydrogen gas from the sun, which sent a wave of solar radiation washing toward Earth."
 

The following is a quote from December 1996's EARTH magazine:

"Earth's cagelike magnetic field surrounds the entire planet, protecting us from the solar wind. 'The solar wind flows around the Earth's magnetic field like river water over a rock', says Jo Ann Joselyn, a scientist with the NOAA. But when an intense solar event occurs, the Sun ejects a mass of charged particles [CME's] that can collide with Earth's magnetic field.

The mass has its own magnetic field, which reacts with our planet's magnetic field the same way that two bar magnets react to each other: Opposite fields attract, identical fields repel.

So if a mass of particles with a magnetic field opposite from the Earth's encounters our planet, the mass will be attracted to the Earth's magnetic field. When this happens, charged particles accelerate and spiral down Earth's magnetic field lines, creating a geomagnetic storm. Sometimes the particles collide with gas molecules in the atmosphere and excite them to give off the light known as the aurora. (italics added)
 

When geomagnetic storms occur, they cause fluctuations in Earth's magnetic field that generates currents. These currents run over Earth's surface and, for the most part, pose no threat to humans. But the currents tend to travel by routes with the least resistance, hitching rides on train tracks, pipelines, and electrical power lines."


Another type of CME is noted below:

"The other way that a subset of all CMEs is most commonly identified in interplanetary space is as 'magnetic clouds' [ Klein and Burlaga, 1982; Zhang and Burlaga, 1988]. Magnetic clouds are defined by the combination of 1) large-scale smooth field rotations, 2) enhanced magnetic field magnitude, and 3) decreased plasma temperatures (e.g., the recent review by Burlaga [1991] and references therein). While only 10% of all CMEs identified with counterstreaming halo electrons fit the strict definition of magnetic clouds, roughly one third of all CMEs in interplanetary space exhibit at least the large, smooth field rotations characteristic of magnetic clouds [ Gosling 1990].One particularly clear case study was recently shown by Gosling et al. [1994] in which post CME loop formation observed with the Yohkoh soft X-ray imager [ Tsuneta et al., 1991] was correlated with the subsequent passage of a flux rope-type CME past Ulysses at 4.6 AU."
This quote from the LASCO project on board the satellite SOHO, states that CME's may actually detach from the sun (although it is believed that there may be some kind of continuing magnetic connection), in what is referred to as a "plasmoid" or "magnetic cloud". It also reflects the fact that CME's can travel some distance from the Sun. This one 4.6 X 93 million miles!

The following quote reflects that not all CME's are directed or attracted by the Earth. So the question... If Hale Bopp is as large as we believe, and possesses an EM field, would it not attract CME's as the Earth does?

"This work is mainly concerned with observations of the white-light and emission line corona during the passage of AR 7973 over the East limb from June 16-20, 1996. A number of CMEs were detected from this region and the corona above the active region was in a continuous state of evolution. - Title: X2.6/1B FLARE ON 9 JULY 1996 AND THE LARGE CME OBSERVED BY THE LASCO/SOHO Research Group : S.Watari(CRL), M.Dryer(NOAA/SEC), Manoharan(Ooty), Russ, Guenther, D.Socker(NRL), M.Andrews(NRL), Brueckner(NRL) Abstract: X2.6/1B occurred at 0905 UT on 9 July 1996. A large CME was observed associated with this flare at the west solar limb by the LASCO/SOHO. The location of the flare was at S10W30. However, no interplanetary disturbance was observed by Wind satellite near the Earth. The relationship between the CME and the flare are still controversial. Hence, this event might be a good example to examine the relation between the flare and the CME. We also have to investigate why the interplanetary disturbance associated with the large CME was not observed at the Earth."
We have seen the effect that the IMF may have upon a comet in a previous section. Gravitational effects may indeed then have the least of all effects upon comets. If this is the case, when Hale Bopp was approximately 3AU out, this CME (identified above) was released and theoretically Hale Bopp could have attracted the CME (see The "two eyes" of Hale Bopp (fig 8)) . Using the square law, Hale Bopp being three times the distance from the sun, would possess a field conservatively nine times as powerful as the Earth. There are a lot of "ifs" here, but very much within the realm of possibility. As Hale Bopp approaches the effect would be of course devastating to our planet. Reversed fields? Seismic destruction? Orbital disruption?

Update 2-23-97

This CME caused millions of dollars in in damage to satellites around the world. The quote below is evidence of the powerful and destructive forces of our universe.

A LASCO image, from January 6, 1997, revealed a large mass ejection directed toward the Earth. As it swelled, it appeared as a halo around the Sun. The mass ejection reached SOHO itself less than four days later, and the solar wind analyzer CELIAS detected an acceleration in the solar wind, from 350 to more than 500 kilometers per second. Soon afterwards, American, Russian and Japanese satellites operating closer to the Earth registered the event, which caused a magnetic storm and bright auroras. The failure of an American TV satellite on 11 January may or may not have been a coincidence.
We are suppossed to be in a time of low solar activity. Does the approach of Hale Bopp have anything to do with this event? Apparently NASA is taking quite a close look at these and other types of threats. Shouldn't we consider the evidence and prepare and educate ourselves as much as possible.

  What is there to protect, except human life? 
 
copyright 1996 gary d. goodwin