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Appendix
and Chapter Notes
Chapter 2:
Hello: Is anyone there?
Marconi
fully expected that radio broadcasting would be resiliant to solar
disturbances compared to telegraphy and telephony, because it used
a very different medium to transmit its signals. While disturbances
from the September 1909 Great Aurora were recorded world-wide in a
variety of telegraph and telephone systems, he considered this storm
and its impacts a lesson to be learned, not by wireless telegraphy,
but by the competing communications technologies. Like the folkloric
Norwegian boy who impudently whistled at an aurora and was killed,
Marconi's expectation that wireless would not be affected by solar
storms was soon revealed to be mere bluster. In 1926, another Great
Aurora lit up the skies, bringing this 25-year sense of security to
an abrupt end. International wireless tests with US short-wave radio
operators attempted to pick up stations in Wales, Argentina, and Peru.
Electrical disturbances interfered with both broadcasting and telegraph
services. Scientists blamed all of this on an unusually large sunspot
visible on the Sun. Exactly one solar rotation later on February 23,
the same sunspot group was positioned as it had been for the January
storm, and again problems erupted on the telegraph wires and in the
ether. This time, short-wave radio reception of stations to the north
of Ames, Iowa were blocked. Stations to the south came through clear
as a bell. The third and final storm of this series arrived a week
later from a different group of sunspots near the center of the sun's
disk. Again, voltage surges in the telephone lines were recorded,
and short-wave reception only improved after the surges ended.
Just as
telegraphy needed the Earth itself to make it work, wireless radio
also needed to have the cooperation of the Earth to make it
work. To get radio waves to skip from a transmitter to a distant receiver
across the Atlantic, something in the atmosphere had to be there to
serve as a convenient reflecting layer. British physicists A.E. Kennelly
and O. Heavyside found out what it was in 1902. It was nothing less
than a new atmospheric layer of charged particles mixed up within
a dilute sea of air. For decades, the 'ionosphere' as we now call
it, went by the name of the Kennelly-Heavyside Layer. The Heavyside
Layer was even immortalized by T.S. Elliot in his poem 'Cats' as the
place where cats go when they die. The actual ionosphere is far less
exciting.
Chapter 3:
Between a rock and a hard place.
In July
1998, electrical power transmission congestion in Wisconsin and Illinois
blocked the transport of power from northern supplies to consumers
in southern states who were sweltering in the heat. Power lines can
only transport a fixed amount of power, and the essential transmission
lines along the electrical superhighway were experiencing the equivalent
of gridlock. Not enough volunteers could be found in the south to
stop using their air conditioners, so the local electrical utilities
had to go to local energy suppliers to purchase temporary 'make up'
energy. Within a few hours, the price per megawatt soared from $20
to $7000 and wiped out the yearly profits from several southern utilities.
A similar problem happened in 1999 during hot weather in the Midwest
and northeast. De-regulation has forced utilities into a wait-and-see
mode where investments in infrastructure are postponed, and new capacity
is not planned. All of these factors work together to make even minor
geomagnetic storms a potential 'straw' which can break the back of
regional electric power pools.
Should
more lines be installed so that gridlock conditions can be reduced?
Not necessarily. The installation of more transmission lines to carry
higher voltages over longer distances also increases GIC susceptibility
with every mile installed. The currently induced voltages are in the
range of 1-6 volts per kilometer and cause GICs that are nearly three
times higher than what was common 20 years ago. The most direct solution
is to increase electrical margins between supply and demand and ride
out the storm. With de-regulation, it is unlikely that private companies
will invest in new, expensive, power plants especially over the objections
of environmentalists. So it seems that although satellite vulnerability
will eventually solve itself through commercial pressures, the electrical
power industry seems stalemated in their choices to mitigate GIC problems
in the future.
Chapter 9:
Business as Usual,
Despite
a miserable 1998 which cost them over $600 million in in-orbit satellite
payouts, insurance companies still regard the risks of in-orbit failures
as a manageable problem. The loss of Intelsat 708 during a launch
in the Peoples Republic of China triggered a Congressional investigation
on the role of commercial space insurance in technology transfer to
the PRC. The August 1999 Cox Report was the outcome of this investigation,
and it publically revealed many of the details of how satellite insurance
operates. Launch services and space insurance markets generated $8
billion in 1997 and $10 billion in 1998. Since private insurers entered
the space business in the 1960's, they have collected $4.2 billion
in premiums and paid out $3.4 billion in claims. Insurers consider
today's conditions a buyers market with $1.2 billion capacity for
each $200 million satellite. There is a lot of capacity available
to cover risk needs.
Like any
insurance policy the average home owner tries to get, you have to
deal with a broker and negotiate a package of coverages. In low risk
areas, you pay a low annual premium, but you can pay higher premiums
if you are a poor driver, live on an earthquake fault, or own beach
property subject to hurricane flooding. In the satellite business,
just about every aspect of manufacturing, launching and operating
a satellite can be insured, at rates that depend on the level of riskiness.
A satellite
owner applies for several types of coverage for a single satellite.
The first phase usually ends with the intentional (as opposed to accidental)
ignition of the rocket engines. This is followed by a phase that ends
when the satellite is inserted into orbit; and a third phase that
begins after a predetermined shake-out period, and lasts for the duration
of the satellites lifetime. This on-orbit, operational phase is considered
a very stable source of revenue when an insurance underwriter carries
several satellites in its insurance portfolio. Space insurance is
syndicated, which means that each underwriter assumes only a percentage
of the risk for each satellite. Typically for a given satellite, 10-15
large insurers (called underwriters) and 20-30 smaller ones may participate.
There are about 13 international insurance underwriters that provide
about 75% or so of the total annual capacity.
To get
insurance, a satellite owner selects an insurance broker who acts
as an intermediary between the insurance underwriters and the satellite
owner. The broker writes the policy, manages transactions and settles
claims. Brokers do not lose money in the event of an accident, but
are paid a commission on the basis of the size of the insurance package
they write. The satellite owner prepares a technical document describing
the satellite and launch vehicle in detail, and any risks associated
with the technology. This is presented to the broker, who then presents
this to the various underwriters during the negotiation phase. This
information is confidential and cannot be divulged to the public.
Brokers and underwriters often retain their own staffs of independent
technical experts, space scientists, and engineers to advise on the
risk factors and to decide upon appropriate premium rates. The policy
is then negotiated, with the broker serving as the intermediary between
owner and underwriter. This can take up to three years prior to launch
for major satellite systems. A 10-20% deposit is paid to the underwriters
no later than 30 days before launch. Typically, the premiums are from
8-15% for the launch itself. In-orbit policies tend to be about 1.2
to 1.5% per year for a planned 10-15 year life span once a satellite
survives its shake-out period.
According
to ..... at International Satellite Brokers in Virginia, this period
was once as short as one year, but has now grown to as long as five
years depending on the perceived riskiness of the satellite. If a
satellite experiences environmental or technological problems in orbit
during the initial shakeout period, the insurance premium paid by
the satellite owner can jump to 3.5 - 3.7% for the duration of the
satellite's lifetime. This is the only avenue that insurers have currently
agreed upon to protect themselves against the possibility of a complete
satellite failure. Once an insurance policy is negotiated, the only
way that an insurer can avoid paying out on the full cost of the satellite
is in the event of war, a nuclear detonation, confiscation, electromagnetic
interference or willful acts by the satellite owner that jeopardize
the satellite. There is no provision for 'Acts of God' such as solar
storms or other environmental problems. Insurers assume that if a
satellite is sensitive to space weather effects, this will show up
in the reliability of the satellite, which would then cause the insurer
to invoke the higher premium rates during the remaining life of the
satellite. Insurers, currently, do not pay any attention to the solar
cycle, but only assess risk based on the past history of the satellite's
technology.
As you
can well imagine, the relationship between underwriters and the satellite
industry is both complicated and at times volatile. Most of the time
it can be characterized as cooperative because of the mutual interdependencies
between underwriters and satellite owners. During bad years, like
1998, underwriters can lose their hats and make hardly any profit
from this calculated risk-taking. Over the long term, however, satellite
insurance can be a stable source of revenue and profit, especially
when the portion of their risk due to launch mishaps is factored out
of the equation. As the Cox Report notes about all of this,
"The
satellite owner has every incentive to place the satellite in
orbit and make it operational because obtaining an insurance settlement
in the event of a loss does not help the owner continue to operate
its telecommunications business in the future. To increase the
client's motivation to complete the project successfully, underwriters
will also ask the client to retail a percentage [typically 20%]
of the risk" [Cox Report, 1999]
According
to Philippe_Alain Duflot, Director of the Commercial Division of AGF
France,
"...the
main space insurance players have built up long-term relations
of trust with the main space industry players, which is to say
the launch service providers, satellite manufacturers and operators.
And these sustained relations are not going to be called into
question on the account of a accident or series of unfortunate
incidents".
Still,
there are disputes that emerge which are now leading to significant
changes in this relationship. Satellite owners, for instance, sometimes
claim a complete loss on a satellite after it reaches orbit, even
if a sizable fraction of its operating capacity remains intact after
a 'glitch'. According to Peter D. Nesgos of the New York law firm
Winthrop, Stimson, Putnam and Roberts as quoted by Space News,
"In
more than a dozen recent cases, anomalies have occurred on satellites
whose operators say they can no longer fulfill their business
plans, even though part of the satellite's capacity can still
be used"
This has
caused insurance brokers to rethink how they write their policies,
and for insurance underwriters to insist on provisions for partial
salvage of the satellite. In 1995, the Koreasat-1 telecommunications
satellite owned by Korea Telecom of South Korea triggered just such
a dispute. In a more recent dispute underwriters actually sued a satellite
manufacturer Spar Aerospace of Mississauga, Canada over the AMSC-1
satellite, demanding a full reimbursment of $135 million. They allege
that the manufacturer 'covered up test data that showed a Spar-built
component was defective'. Some insurers are beginning to balk at vague
language which seemingly gives satellite owners a blank check to force
underwriters to insure just about anything the owners wish to insist
on.
One obvious
reason why satellite owners are openly adverse to admitting that space
weather is a factor, is that it can jeopardize reliability estimates
for their technology, and thus impact the negotiation between owner
and underwriter. If the underwriter deems your satellite poorly designed
to mitigate against radiation damage or other impulsive space weather
events, they may elect to levy a higher premium rate during the in-orbit
phase of the policy. They may also offer you a 'launch plus five year'
rather than a 'launch plus one year' shakeout period. This issue is
becoming a volatile one. A growing number of stories in the trade
journals since 1997 report that insurance companies are growing increasingly
vexed by what they see as a decline in manufacturing techniques and
quality control. In a rush to make satellites lighter and more sophisticated,
owners such as Iridium LLC are willing to loose six satellites per
year. What usually isn't mentioned is that they also request payment
from their satellite insurance policy on these losses, and the underwriters
than have to pay out tens of millions of dollars per satellite. In
essence, the underwriter is forced to pay the owner for using risky
satellite designs, even though this works against the whole idea of
an underwriter charging higher rates for known risk factors. Of course,
when the terms of the policy are negotiated, underwriters are fully
aware of this planned risk and failure rate, but are willing to accept
this risk in order to profit from the other less risky elements of
the agreement. It is hard to turn-down a five year policy on a $4
billion network that will only cost them a few hundred million in
eventual payouts. The fact is that insurers will insure just about
anything that commercial satellite owners can put in orbit, so long
as the owners are willing to pay the higher premiums. Space weather
enters the equation because, at least publicaly, it is a wild card
that underwriters have not fully taken into consideration. They seemingly
charge the same in-orbit rates ( 1.2 to 3.7%) regardless of which
portion of the solar cycle we are in.
Chapter
10: Living with a Star.
Modern
science's renowned ability to predict the future of many different
physical systems is a dazzling accomplishment, and the culmination
of thousands of years of careful study of the physical world. So,
why can't we just 'plug in the numbers' and predict when the next
solar storm will tackle one of our satellites, turn the lights out
in Bangor, or irradiate one of our astronauts? Because the sun and
the earth are a complex system, and we lack enough data to see the
big picture clearly; but it's not for a lack of trying.
Solar
flares are among the most awesome outbursts of energy in the solar
system: a billion hydrogen bombs of energy blast matter into space.
Invisible beams of high-energy protons leap out into the void. If
the Earth is in the way, the proton beams penetrate into the ionosphere
like a knife through soft butter, and cause chemical and electrical
changes across the entire daytime hemisphere of the Earth. Like lightning
discharges from a thunderstorm, they can also be spectacular and beautiful
in their own deadly ways.
The Great
Aurora of September 9, 1859 lit-up the skies around the world, and
caught astronomer Richard Carrington's eye just as he was about to
end his observing session at the telescope. Carrington was an avid
watcher of sunspots, and he had been watching a spectacular sunspot
round the western limb of the sun during the last few days. Within
minutes, a powerful optical flare burst into light and then vanished.
Meanwhile, miles away at the Kew Observatory outside London, the local
magnetic field went haywire. This flare did much more than merely
tilt compass needles and make a few astronomers sit upright. In France,
telegraphic connections were disrupted as sparks literally flew from
the long transmission lines. Huge auroras also blazed in the sky as
far south as Hawaii, Cuba and Chile. People spoke about this, now
long-forgotten, event much as we have obsessed about 'Killer Asteroids'
in recent years.
Despite
the coincidence of flare and aurora, Carrington's observation was
actually a fluke. Astronomers know that such brightenings visible
to the eye through a telescope are literally a once-in-a-lifetime
event, and require especially titanic releases of energy on the sun.
For the next 50 years after Carrington's sighting, many careful studies
were made of the solar surface and magnetic storm records, but no
other sudden brightenings of the solar surface were ever seen again.
It wasn't until the invention of the spectroheliograph, and its successor
the visible light spectrohelioscope, between 1892 and 1910 that many
more sudden brightenings were captured, and their geomagnetic impacts
could be properly assessed. Ultimately, the only proven way to anticipate
solar flares, and the geomagnetic and ionospheric effects that might
follow, is to watch the solar surface itself. Constantly.
Since
the 1960's, solar physicists have known that sunspots with opposite
polarity cores, called 'unbrae', within the same envelope, called
'penumbrae', were a potent spawning ground for flare activity. If
a flare had been spotted near an active region, the odds were excellent
that there would be more flares to follow from this same region over
the course of the next few weeks. It didn't matter how big the sunspot
group might be. What counted was how tangled-up the magnetic field
was in a small region of the solar surface. In the 1970's, new magnetic
imaging technologies allowed flaring regions to be correlated with
areas where strong shearing was occurring: magnetic fields with opposite
polarities were trapped in regions where gas motions were dynamically
moving the magnetic fields around in very small parcels of gas. This
seemed to be the crucial observational clue to anticipating when a
flare is likely to breakout.
The BearAlert
program eventually established an 'eight-fold way' for evaluating
whether conditions were ripe for a flare event or not. Current, official,
techniques used by NOAA's Space Environment Center use images of the
entire sun, rather than detailed studies of individual active regions,
and tend to be accurate only about 25% of the time. The BearAlerts,
with their much more detailed assessments of individual sunspot groups,
scored correct predictions for M and X-class flares about 72% of the
time. What is also encouraging is that the method developed by Zirin
and Marquette rarely misses the really big M-class flares that
can do astronauts and satellites serious harm. The amount of lead-time
we have for solar flares has now expanded from literally a few minutes,
to several days.
There
is some indication, however, that a perfect record of correct calls
may be forever out of reach. Solar activity, at the scales that trigger
flare events, is largely a random process, just as the pattern of
lightning strikes during a thunderstorm.
Ludwig
Bierman at the University of Gottingen was a comet specialist, and
for some time had puzzled over comet tails, and why it was that they
pointed in the directions that they did. The tails should always point
directly away from the sun if the only thing acting on them was the
pressure from sunlight. But by 1951, the data he had accumulated over
the years had turned up another oddity. There was a significant difference
between where the tails were actually pointing, and where the light
pressure should have pushed them. This could only mean that some other
force was acting on them. Comet tails, like million-mile-long windsocks,
pointed in the direction that the solar wind was blowing near them.
During
the first few years of the Space Age, the solar wind came into even
clearer view, thanks to the Mariner 2 spacecraft launched in 1962.
Despite what it could do to comet tails, there isn't really much to
this wind at all.
The number
of geomagnetically disturbed days rises and falls with the sunspot
cycle. The largest number seems to peak a year or so before, and a
year or so after, sunspot maximum. The reason for this is not known.
Also, these disturbances seem to be more intense in the March-April,
and September-October periods. Here we think we understand this pattern
a little better. The Earth's orbit is tilted five degrees to the equator
of the sun. This means that there will be two 'seasons' during the
Earth year around the Equinoxes, when it is located at solar latitudes
where sunspots and other active regions are most common. Like a soldier
peering over the edge of a foxhole, at these latitudes, more of the
solar storminess catches up with you. The solar equatorial zone, itself,
is rather quiet during much of the solar cycle. If you want the best
chance of seeing a dramatic aurora, wait until sunspot maximum conditions
prevail, and visit northern latitudes during the March and September
Equinoxes.
As interesting
as Kp is, it does little to give you a meaningful advanced warning
of what will soon be happening where you are located. Once you see
the Kp index growing in size to become a Major Storm, the damage to
your technology has already been done. Historical information about
past storms tells the unhappy tale that, by the time you see Kp grow
to the level of a medium-sized storm with Kp = 6, you have a roughly
one in five chance it will continue to grow into a large storm with
Kp =7.0. You also have a roughly one in 15 chance it will become a
major storm with Kp=9. It only takes a few hours for these kinds of
changes to play themselves out. More troubling than this, geomagnetic
conditions can look fairly normal for hours, then within minutes,
suddenly deteriorate into a severe storm. Despite its limitations
for advanced warning, Kp is in many ways the only indicator that is
readily available each day, so a variety of groups and industries
find even this kind of information better than none at all: the electrical
power industry for insta
Although
plasmas, fields and currents form systems of staggering complexity,
there are still consistent patterns of cause and effect that can be
traced with considerable mathematical precision. There is nothing
ad hoc about how a current of particles will generate a specific amount
of magnetic field strength. It doesn't matter if the current is one
ampere of electrons in a wire, or a dilute 500,000 ampere river of
plasma orbiting the earth. Maxwell's famous equations, combined with
suitable 'equations of motion', are in principle all that you need
to describe the essential features of any 'magneto-hydrodynamic' system
such as the earth and sun. But, even with the theoretical game plan
clearly defined, there is still a lot that is left unspecified. Theorists
have a bewildering number of mathematical choices to make in deciding
which ingredients to keep and which to throw out. The more sources
and interactions you add to your equations, the messier they become,
and the harder it is to wrest a concrete mathematical prediction from
them. High-quality data is the only looking glass that lets space
scientists hit upon the right clues to guide them. Like learning how
to dance, it is important to start with the correct foot forward,
and only a careful study of Nature gives us the right choreography.
Eventually, space scientists managed to win their way to a rather
firm set of procedures for tackling questions about the sun-earth
system. These 'arrivals' were not in the form of some monolithic,
single, comprehensive theory of how the whole shebang worked, but
a series of minor victories which formed their own separate tiles
in a larger puzzle.
Astronomers,
armed with telescope and spectroscope, investigated the solar surface,
and pieced together the physical structure of the photosphere-chromosphere-corona
region. They dissected the chemical compositions of the solar gases,
measured their temperature, density, and speed and crafted a working
model of the solar atmosphere. They used powerful new 'Zeeman-splitting'
techniques to measure surface magnetic fields. With Maxwell's equations,
the magnetic data helped theorists build models of the geometry of
this field around sunspots and extend them deep into the corona. By
1960, a preliminary theory of why there is a sunspot cycle, and why
sunspots occur, was hammered-out by Eugene Parker at the University
of Chicago and Horace Babcock at the Hale Observatories. Parker also
went on to craft a ground-breaking theory, and mathematical description,
of the solar wind as it leaves the coronal regions and flows throughout
the solar system. Solar physics was, essentially, described by the
complex mathematics of magneto-hydrodynamics. The particular phenomena
we observed was 'only' the working-out by the sun of specific mathematical
solutions, driven by its complex convecting surface. What remained
to be understood were the details of just how the solar magnetic field
was generated, how the corona was heated, and why solar flares and
other impulsive events get spawned. The missing link seemed to be
the various gyrations of the magnetic field itself, but only new instruments
in space would let scientists chase the magnetic forces down the rabbit's
hole of decreasing size.
By the
way, you should always keep in mind that things could be far worse
for us than they are! For decades, astronomers have been studying
stars that are close cousins to our sun; a middle aged, G2-class star.
At Mount Wilson Observatory, careful measurements of some of these
stars show a distinct rise and fall in certain spectral lines which
on our own sun are indicators of solar activity. These stars also
show periodic 'sunspot cycles' with periods from a few years, up to
30 years per cycle. Others show a constant level of activity, as our
own sun would have during the Maunder Minimum between 1610 and 1700.
So, solar activity is not unusual among the kinds of stars similar
to our sun. What is rather alarming is that some of kindred stars
belt-out super flares from time to time. In fact, according to Yale
astronomer Bradley Schaefer, sun-like stars normally produce one of
these superflares every century, "One of these cases I have is
a star, S-Fornax, where for a 40-minute period it was seen to be three
magnitudes brighter than usual". The power from the flare made
the star appear nearly 20-times brighter than usual. One of these
superflares would be about 10,000 times more powerful than the solar
storm that caused the 1989 Quebec blackout! According to Schaefer,
portions of the surfaces of the outer ice moons of the solar system
might be melted, much of the ozone layer would be destroyed, and the
entire satellite fleet would be permanently disabled. It is believed
that the reason the sun doesn't have these flares is that it doesn't
have a close companion star or planet that is magnetically active,
and able to tangle-up our sun's magnetic field.
Meanwhile,
back at the earth, the challenges were nearly as daunting. The shape
of the earth's magnetic field was eventually defined by numerous ground-level
measurements, and with Maxwell's equations, extended thousands of
miles into space. Although the general shape was still much like that
of a simple bar magnet, there were noticeable lumps to it that followed
geological changes in surface rock conductivity, and sub-surface irregularities
reaching all the way to the core of the earth itself. By the 1930's,
physicists Sydney Chapman and Vincenzo Ferraro had mathematically
described the impact that an 'intermittent' solar wind would have
upon the earth's magnetic field. It was a staggering tour de force,
linking together many separate geophysical systems and phenomena.
The compression of the sunward side of the field would eventually
lead to the amplification of a powerful ring of current flowing in
the equatorial zone. Aurora had been studied meticulously since the
19th century, and eventually gave up their quantum ghosts once the
spectroscope was invented. Something was kicking the atmospheric atoms
of oxygen and nitrogen so that they glowed in a handful of specific
wavelengths of light. Through the rather contentious technical debates
beginning with Kristian Birkelund in 1896, and ending with Hannes
Alfven in the 1950's, the general details of how aurora are produced
came into clearer view. Some process in the distant geotail region
was accelerating currents of electrons and protons along polar magnetic
field lines. Within minutes, the currents dashed against the atmosphere
and gave up their billions of watts of energy. There was, however,
no detailed mathematical model that could recover all of the specific
shapes and forms so characteristic of these displays. What was certain,
however, was that we were living inside the equivalent of a TV picture
tube, and the electron beams from the distant geotail region were
drawing magical shapes on the phosphor screen of the sky.
The dawn
of the Space Age had brought with it an appreciation of most of the
main ingredients to the complete geospace environment. All that seemed
to be lacking in moving the frontier forward was more data to describe
the geospace system in ever more detail. New rounds of complex equations
needed to be fed still more detailed data to keep them in harmony
with the real world. Space physics had reached a watershed moment
where mathematically precise theories were sorely in need of specific
types of data to help them further evolve. One small step along this
way was to create a series of 'average' models of the particles and
fields in geospace.
NASA became
a leader in developing and refining models of the earth's environment
through the Trapped Radiation Environment Modeling Program (TREMP)
in preparation for the Apollo moon landings. The models combined the
measurements made by dozens of satellites such as Telstar and Explorer,
and even instruments carried aboard the Gemini spacecraft. They didn't
attempt to explain why the conditions were what they were,
or how that got that way. Unlike the specific theories of the sun-earth
system and its various components, TREMP program models, such as AE-8
and AP-8, were merely statistical averages of measured conditions
in space and in different localities during solar maximum and solar
minimum conditions only. They could not predict conditions that had
not already been detected or could be extrapolated from the smoothed
averages. The models did not include solar flares or other short-term
and unpredictable events that can substantially increase accumulated
radiation dosages. This was the best that could be done by the 1970's,
and it is amazing that these models are still in wide use over 30
years later. Although they are adequate for designing satellite radiation
shielding, they are useless for forecasting when the next storm will
arrive. Some researchers don't even think they are all that useful
for high-accuracy satellite shielding design.
Some sample
headlines from weekly journals such as 'Space News' (See bibliography)
"Insurers
Beleaguered by Rash of Failures in '98"
"Space-weather
El Nino has astronomers worried"
'Digital
Flub: Bank Computers Take a Hit'
"NASA
Hunts for Satellites to Carry Science Payloads"
"$1.5
billion trans-Atlantic fiber optic cable project planned"
"Global
Crossing to Expand Transatlantic Capacity Ahead of Schedule"
"Satellite
Makers Use Cheaper, Faster Approach: Off-the-shelf Parts allow smaller
firms to compete"
"Insurers
Warn Against False Expectations"
"Solar
Storm Eyed as [Telstar 401] Satellite Killer"
"Space
Weather Monitoring Faces Funding Woes"
"NASA
Urged to Pursue Study of Radiation Effects"
"SOHO
Data May Enhance Solar Storm Prediction"
"Insurers
Battle With Satellite Makers Over Quality Control"
"Operators
Place High Value on Space Weather Forecasting"
"[It's]
Official: Geostationary Satellites Will Disappear"
"Study
Explores Space Weather Risk to Natural Gas Pipeline in Finland"
"Satellite
Failures Spur Power-Amplifier Developments"
"Solution
to satellite defect still eludes Matra"
"Wary
Investors Avoiding Satellite Deals"
"Iridium
Satellites Please Motorola, Despite Losses"
"Vague
Satellite Policies Increase Insurance Claims"
"Insurers
Plan to Raise Premiums: Underwriters feel pressure of mounting satellite
claims"
"Japan
Developing Satellite to Warn of Solar Flares"
"More
In-Orbit Spares Planned: Recent failures spur steps to guarantee service"
"Globalstar,
Iridium Enjoy Soaring Market Value"
"ICO Plans
to Cut Costs, Delay Service"
"Immarsat
Approves Internet Satellites"
"Motorola
Gives Iridium Deadline"
"Iridium
Officials Insist Venture Will Survive"
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