Satellite return may be challenging
U.S. military hopes to destroy
out-of-control spy satellite before it reaches earth
BY NANCY HOGLAND |
February 17, 2008
A satellite that could have been used to survey damage from
disasters now has the potential of causing one.Air
Force Gen. Gene Renuart, who heads the U.S. Northern Command,
said an out-of-control spy satellite, estimated to be about the
size of a school bus -- is falling to Earth and is expected to
land in late February or early March – possibly somewhere on
this continent.
“We're aware that this satellite is out there,” Renuart
said. “We're aware it is a fairly substantial size. And we know
there is at least some percentage that it could land on ground
as opposed to in the water. As it looks like it might re-enter
into the North American area, then the U.S. military along with
the Homeland Security Department and the Federal Emergency
Management Agency will either have to deal with the impact or
assist Canadian or Mexican authorities.”
In an attempt to avoid such a situation, Gen. James
Cartwright, Vice Chairman of the Joint Chiefs of Staff,
announced last week that a modified version of the Aegis
Sea-Based Missile Defense system will be used in an attempt to
intercept the falling U.S. satellite and destroy it before it
hits the earth.
President George Bush approved the attempt, military
officials said, because the satellite’s fuel tank might survive
a crash and spread the rocket fuel, hydrazine, possibly
endangering humans. The shoot-down attempt will occur some time
after the NASA Shuttle returns this week.
The satellite, typically used to gather visual information
about adversarial governments and terror groups and to survey
damage from hurricanes, fires and other natural disasters, was
launched in December 2006. However, it lost power and its
central computer system failed shortly after take-off.
Unfortunately, if the missile intercept is not successful,
it will be difficult to predict where the point of impact will
be until the satellite falls to about 59 miles above the Earth
and enters the atmosphere. It will then begin to burn up, with
flares visible from the ground, said Ted Molczan, a Canadian
satellite tracker. From that point on, he said, it will take
about 30 minutes to fall.
According to Chuck May, the manager of the Planning and
Disaster Recover Branch of Missouri State Emergency Management (SEMA),
this short notice would make it next to impossible to warn
people of the impending danger.
“If NASA or Department of Defense officials learned that
chunks of the satellite were going to hit anywhere in the U.S.,
of course, they would do what they could to notify people, but
obviously it would all tie down to how much warning we had,” he
said. “With only 30 minutes notice, I don’t know what could be
done. If county or law enforcement officials could be notified
in time to warn people, they would. But there are so many ‘ifs,’
it’s hard to say exactly what measures could be taken.”
The military plan to attempt to intercept the satellite
has been hailed by advocates of missile defense systems as a
prime example of the peaceful benefits of the weapons. “The
investment and the proven technology of our country's missile
defense systems has given our nation and our military an option
which it never had before to protect human life globally from
falling objects from space,” said Riki Ellison, president of the
Missile Defense Advocacy Alliance. “Our country's investment and
leadership internationally in Missile Defense provides global
options that make our world a safer place,” he added.
But the plan has drawn criticism from those who see it as
a way to justify anti-satellite missile systems. "In the history
of the space age, there has not been a single human being who
has been harmed by man-made objects falling from space," Michael
Krepon, co-founder of the Henry L. Stimson Center, told the
Washington Post. "There has to be another reason behind this.”
However, if the missile is not able to shoot down the
satellite and it actually hits a populated area, the Federal
Emergency Management Agency and disaster response organizations
may have to respond.
“With a couple exceptions, emergency response plans are
set up to respond to all hazards. The exceptions would be
catastrophic events that are area specific – in Missouri we have
additional plans in the event of a New Madrid fault quake;
Florida’s plans include hurricane response. However, no one at
either the state or federal level has developed anything
specifically dealing with incoming asteroids or other items
falling from the sky,” May said.
Matt Hackworth, communications officer with Church World
Service, a relief ministry umbrella for 35 Protestant, orthodox
and Anglican denominations, said his group prepares for
disasters of every kind.
“Our job is to respond to disasters of any kind – natural
or technological. We do have measures in place to work remotely
in case New York, our headquarters, was impacted. But we aren’t
exactly ‘disaster specific.’
“Besides, look at Greensburg, Kansas. Their claim to fame
was that they were hit by a meteorite. They weren’t obliterated
by an asteroid, but instead by a tornado.”
Asteroids have, however, done their share of damage. In
1908, an asteroid exploded in the air above Siberia, flattening
thousands of square miles of forest. More than 150 meteor
crashes have carved out craters in Arizona, Missouri and on
Mexico’s Yucatan Peninsula. They continue to keep sky watchers
glued to their telescopes.
In the past few years, scientists and astronomers had been
keeping a close eye on two asteroids in particular – one named
1997 XF11 and on another dubbed 2004 MN4.
In 1998, XF11 was originally thought to be on a collision
course with Earth with a direct hit expected on Oct. 26, 2028.
However, National Aeronautics and Space Administration (NASA),
which has closely monitored its orbits over the past 10 years,
now estimates XF11’s passage at 591,000 miles away or about 2.5
times farther than the moon.
In December 2004, scientists set the odds at 1 in 37 that
the giant space rock 2004 MN4 would slam into earth on April 13,
2029. And while the asteroid will still be making a close brush,
at less than 30,000 miles, scientists said additional
observations had reduced the chance of impact to zero.
Although scientists with the NASA’s Near Earth Object
Program report they are not concerned about the two asteroids,
or any of the other 108 on the watch list of “potentially
hazardous objects,” they, along with the U.S. Space Command and
the Department of Defense continue to refine a process that will
allow them to gather and analyze date regarding impending Earth
impacts from asteroids or comets, assess possible damage
stemming from such an impact and to notify top officials. They
are expected to also evaluate possible evacuations or emergency
preparations.
In the meantime, scientists agree that it is only a matter
of time before another comet hits home.
“It's like a game of cosmic darts,” said astronomer Clark
Chapman on the PBS show Nova. “It could just as likely happen
tomorrow as some day 300,000 years from now.”
And if falling satellites and asteroids aren’t enough to
keep you awake at night, scientists are looking upward, waiting
and watching for the next major solar storm, which has the
potential of wiping out all communications.
At more than 869,919 miles wide, the sun makes up
approximately 99.86 percent of the mass of the entire solar
system. The total energy radiated by the sun averages 383
billion trillion kilowatts, the amount of energy generated by
the explosion of 100 billion tons of TNT every second.
However, the energy released by the sun is not always
constant. Once in a while, the sun releases an even larger
amount of energy with intense magnetic fields in the form of a
solar flare – an explosive burst of hot gasses.
In 1859, solar observers noted the development of numerous
sunspots on the sun's surface. What followed was an explosive
release of magnetically charged energy that reached the earth’s
surface in hours. The magnetic fields, in direct opposition with
the earth’s magnetic fields, were so intense that there were
severe interruptions of communications systems. Telegraph wires
were burned to a crisp and created wildfires as they dropped to
the ground.
Since that time, other solar storms have caused major
malfunctions to communications satellites and affected
television, radio and telephone signals.
Hackworth said such an event, on the back of another
disaster, could be disastrous to organizations that rely on
communications.
“Can you imagine a disaster where you couldn’t make a
conference call to coordinate the response? The disaster world
relies on communication. More and more we rely on technology to
assist us in our work. If we had a major breakdown in
communications, whether it be from huge solar flares or from an
EMP bomb, we would have massive problems,” he said.
http://heasarc.gsfc.nasa.gov/docs/euve/euve.html
|