By CATHY KARLIN ZAHNER
The Kansas City Star
   KANSAS CITY, Mo. (AP) -- Keith L. Partain, a Tulsa researcher,
would like to put an end to speculation over the Tri-State Spook
Light, but it won't be easy.
   In the century since it was first sighted, the spook light has
offered enough mystery to spin a perfect Halloween tale. Several,
in fact.
   According to local lore, the light that floats along a lonely
backwoods road southwest of Joplin is the tragic spirit of two
Quapaw Indian lovers who committed suicide nearby.
   Another story describes the light as the glow of a lantern used
by a miner still searching for his children, kidnapped by Indians
in the 1870s.
   One Carthage resident wrote a book this year speculating that
the light is a guiding system for interplanetary travel.
   More down-to-earth observers believe the spook light is merely
reflected headlights from cars on a nearby highway, or perhaps
stems from luminous swamp gases or blinking government survey
signals.
   Partain, 34, a laboratory technician, has developed a new theory.
   Comparisons of sightings and photographs led him to project that
two types of lights actually appear on Spook Light Road, about
three miles southwest of the Missouri-Oklahoma-Kansas border.
   Most of the time, spook light watchers are seeing nothing more
than car headlights refracted up from Interstate 44 by water vapors
from the nearby Spring River, Partain said. The highway is seven to
10 miles from the road.
   But about every 10 years, the real spook light appears in the
form of ball lightning, he said.
   Ball lightning is a self-contained sphere of electrical energy
in which lightning appears in the shape of a sphere rather than
vertical bolts. It is a rare, natural phenomenon that is
unpredictable and, therefore, difficult to study, scientists say.
   "The real spook light exists, but it is extremely rare," said
Partain, whon has degrees in entomology and zoology. "When all you
see is a little wriggle at the end of the road, it's one car
following another on a distant road."
   He said he became intrigued with the spook light seven years ago
after reading about it in a magazine. His conclusion that ball
lightning accounted for some of the sightings stems from a March
1977 photograph by Joplin Globe reporter Marta Churchwell along
with published reports of several sightings.
   The photograph showed a ball of light with a connected filament
shooting off from the parent body, he said. Because the ball was in
front of the treeline, its appearance was not distorted by tree
branches, so such a filament would indicate the presence of ball
lightning, he said.
   One of the sightings that also underlies his theory occurred in
1955. During the sighting, the spook light was seen by an observer
whose back was to the general direction of the highway which is now
Interstate 44, ruling out headlight refraction as a cause, Partain
said.
   Comparisons of the sightings and photographs revealed that they
occurred when there were no or few sunspots, Partain said. Thus, he
speculates that the appearance of ball lightning is linked to low
sunspot activity, nighttime and periods surrounding the fall and
spring equinoxes.
   The three factors combine, he believes, to weaken the earth's
ionosphere to allow radiation from outside the solar system to fall
on the Joplin area and create ball lightning.
   "There is a bump, or anomaly, in the earth's magnetic field in
that area which could attract cosmic radiation," Partain said.
   Ideal conditions for ball lightning occur throughout an 18-month
period every 10 or 11 years, he believes.
   Harry Shipman, a professor of physics at the University of
Delaware and former education officer for the American Astronomical
Society, said Partain's belief that the light was caused by either
headlights or ball lightning appears to be logical.
   "Ball lightning may be behind a lot of UFO reports and things
like that," Shipman said. "He's also got a point that when you
look into UFO reports, a lot of them can be headlights coming from
unexpected areas."
   Shipman said, however, that he would be surprised if the sunspot
cycle could be correlated with ball lightning in any one place.
   Despite the scientific explanations, some spook light watchers
believe it is a mystery. Some, such as Jack Winter of Afton, Okla.,
say the land has too many hills and trees to enable headlights to
shine through.
   "It's still an open question with most people here," said
Harlan Stark, a farm editor and reporter for the Neosho Daily News.
   "Many residents take out-of-town guests to see the spook light
and enjoy its aura of mystery. I imagine most of them wouldn't like
to see it explained too well," he said.
   Suzanne Gilpin, assistant manager of the Joplin Chamber of
Commerce, said people from as far away as Texas and California have
inquired about the spook light since it was featured on the
television show "Real People" several years ago.
   "On a nice evening, especially at this time of year, it can be
bumper-to-bumper down there," Mrs. Gilpin said.