The Krone Experiment by J. Craig Wheeler

located in one place and the apparent movement is just due to
the random bouncing of the subsequent wave.”
    “Possible,” allowed Danielson, “and more
comfortable, but the data still seem to suggest that the source is
moving.”
    “How much energy is involved?” queried
Isaacs.
    “Well, of course, the power we detect depends
on both the power at the source and the distance to our detectors.
If we assume the source is, on the average, at the distance of one
Earth radius, about four thousand miles, then the seismic energy
flux at the detector corresponds to a source power of about one
thousand megawatts — big for a power station, but pretty small
potatoes compared with all the seismic energy in the Earth at a
given time. Which is why the signal is hard to detect and
analyze.
    “Since we don’t really know the nature of the
source, it’s difficult to associate an energy with it; that is, it
could sit in one place and emit bursts of energy that reverberate,
or it could represent a continuous supply of energy, as we believe.
A ballpark estimate is the total energy liberated in one
characteristic period, ninety minutes. In one period that would be
about one per cent of the energy of a one kiloton nuclear
event.”
    “That’s a maximum estimate, isn’t it?” asked
Isaacs.
    “Yes, sir,” replied Danielson, “within a
factor of a few, given that the source is confined to the
Earth.”
    “One hundredth of a kiloton,” mused Isaacs.
“That’s too small to be a nuclear device, and if the source is
closer, the energy estimate only goes down. Still, if that amount
of energy is being liberated artificially on the surface, we should
be able to see other signs of it in the optical or infrared —
somewhere.
    “The most reasonable assumption,” Isaacs
continued, “is that this is some natural seismic event that happens
to have a period of about an hour and a half, regular fault
slippage of some kind.”
    Danielson raised a finger and opened her
mouth to interject, but Isaacs interrupted her, “Unless, of course,
you can prove the source is actually moving about.
    “Obviously, I’m unconvinced this signal is
anything but some sort of natural phenomenon,” Isaacs said, “but I
am convinced we need to nail it down. Suppose you’re right and it’s
not related to natural fault slippage somewhere, do you have any
guess as to what it might be?”
    “No. If the source is moving around in the
Earth as I think the data suggest, it’s a total paradox. Fault
slippage at different points on the Earth shouldn’t be
correlated.”
    Isaacs leaned back in his chair, toying with
a pencil. “A period of ninety minutes still sounds suspiciously
like some artificial phenomenon — keyed to somebody’s time clock.
If your positions are right, Egypt and whatnot, it’s not a local
man-made thing, but I’d like to make sure that is ironclad.”
    Isaacs sat up at the desk and gestured to
Danielson with the pencil. “You had better make this a matter of
some priority until it’s resolved. We need to know the period, if
it really is one, more accurately. If the period is not precisely
defined, that’s good evidence of a natural phenomenon. If the
period turns out to be exactly ninety minutes, it will be a
man-made event despite present evidence to the contrary.
    “We need to know the location, whether or not
it is moving around. When you have a location, we can look for some
other evidence of its existence and nature. If it’s seismic in
nature, there should be some correlation with fault location and
activity. Any other suggestions?”
    Danielson paused a moment in concentration
before she spoke. “No sense speculating without more data. It will
probably be useful to get records from civilian seismic stations,
universities here and abroad. We can look for correlations among
events that would pass unnoticed in any single record. That should
help with both the period and the location.”
    “That’s fine,” said Isaacs with