A sophisticated new
Earth-imaging satellite with sharp eyes, nimble moves and a broad memory was
launched Tuesday, riding the ever-dependable Delta 2 rocket into orbit during a
flawless ascent that set a new reliability mark for modern space boosters.
The
uneventful countdown was punctuated by an on-time liftoff at 11:35 a.m. local
time (2:35 p.m. EDT; 1835 GMT) from Vandenberg Air Force Base, California. The
12-story rocket raced
off the launch pad, roaring up through a deck of low clouds as it began to
arc southward with the WorldView 1 satellite tucked neatly in its nose cone.
It took 73 minutes for the
two-stage launcher to accomplish the job of hoisting the two-and-a-half-ton
satellite to the proper orbit, then safely deploying WorldView 1 for its
mission to survey the globe with advanced imaging capabilities.
Cheers and applause burst
out in the control rooms when the successful launch was confirmed, and the joy
seemed a little sweeter this time because a milestone for the rocket business
had just been achieved.
It was the 75th consecutive
successful ascent for the Delta 2 rocket. No other single rocket design in the
current era has strung together such a long and spotless track record.
Delta 2 has been perfect
since May 1997, amassing its consecutive string by launching spacecraft for
military, NASA and commercial users, including the Global Positioning System
satellites, the twin Mars
rovers Spirit and Opportunity, the Spitzer Space Telescope and the
Mercury-bound MESSENGER orbiter. In the rocket's 130 flights overall since
debuting in 1989, 128 of those launches have been successful.
"I love the Delta 2.
We've been able to meet schedule, we've been able to put some exciting,
exciting payloads out into orbit. I think one of the things that's
revolutionized the world is the GPS system. We were the ones that put all of
those satellites up into orbit," said Kris Walsh, United Launch Alliance's
director of NASA and commercial programs for the Delta rocket.
"So I think it's been
a tremendous boon for the United States government and commercial (customers).
It's a great little rocket. I'll continue to fly it as long as I can."
The Delta 2's future
There are 25 Delta 2
rockets remaining to fly over the next few years. "It's a pretty firm
number, if we don't end up starting production again," Walsh said.
The
future launches include 11 flights for NASA counting next week's Dawn
asteroid probe, the five remaining GPS 2R satellites for the Air Force, three
commercial missions and six rockets not yet sold, Walsh said.
Keeping the Delta 2 around
for the long-term depends on finding a government partner. The Pentagon and
NASA have shared the costs over the past years. But the military will soon end its use of
the Delta 2 in favor of the Evolved Expendable Launch Vehicles.
The Air Force has backed
the Delta 2 since the rocket's earliest days for launching the GPS
constellation. But after the five remaining satellites in the current series
are launched soon, the Air Force will be turning its attention to
next-generation spacecraft that will fly on the larger Atlas 5 and Delta 4
boosters.
That will leave NASA as the
main government user of Delta 2. Thus far, the space agency has been reluctant
to fund future production of the rocket and the associated infrastructure
maintenance entirely on its own.
"We'll continue (Delta
2) as long as it's a viable rocket and we have a government anchor
customer," Walsh said.
The new sharp-eyed orbiter
Benefiting from the
rocket's consecutive success No. 75 was the WorldView 1 spacecraft. Circling
300 miles (482 kilometers) above the planet in polar orbit, ringing around
Earth once every 95 minutes, the commercial Earth-imaging satellite will offer
a clarity not possible by any civilian satellite in orbit today.
Despite the lofty perch in
space, the satellite's remarkable vision can see objects on the ground as small
as 20 inches (50 centimeters) across. And its advanced picture-taking sensor
package can produce such images with half-meter resolution covering 290,000
square miles (751,100 sq. kilometers) of the planet's surface per day.
The anticipated quality has
the U.S. government signed up as a customer to receive WorldView's images of
specific global hot spots and areas of interest for intelligence-gathering. And
the growing potential of commercial applications for such imagery ranges from
urban planners, real estate developers, environmental monitors and users of the
wildly popular Google Earth.
DigitalGlobe,
based in Longmont, Colorado, has operated its QuickBird satellite for nearly
six years. But the imminent addition of WorldView 1 promises to generate five
times the image-collecting capacity.
"Being able to satisfy
many more customer orders and larger area collections is really the big
differentiator from QuickBird and our new satellite WorldView," said Chuck
Herring, DigitalGlobe's director of corporate communications.
The two spacecraft working
in tandem will allow imaging a specific spot on Earth each day, cutting the
current three-to-five-day "revisit" rate of the solo QuickBird.
WorldView 1 also boasts a
much greater agility than its predecessor. Orientation-controlling gyroscopes,
called control moment gyros, are flying on the Ball Aerospace-built craft,
marking the first time such devices have been used by a commercial imaging
satellite, Herring said.
The gyros will enable the
spacecraft to point itself about 10 times faster than QuickBird. That should
increase the satellite's picture-shooting time because imaging cannot begin
until after the craft completes its turns and takes aim.
"The biggest thing is
our ability to collect a lot more imagery," Herring said.
DigitalGlobe officials are
anticipating being able to show off initial imagery from WorldView 1 in about a
month, just in time to coincide with the sixth anniversary of QuickBird's
launch on a Delta 2 rocket from Vandenberg.
If all goes well, WorldView
1 should be fully operational by year's end.
The growing market for
Earth-imaging
Until WorldView enters
service, QuickBird remains the highest resolution commercial satellite of its
type. But WorldView 1 will be slightly better, offering 0.5-meter (1.6-foot)
meter clarity versus 0.6-meter (about two-foot).
"For the casual
user...you wouldn't see a huge difference in the imagery. (To) an imagery
analyst, there is a difference in the resolution," Herring said.
A key constituent of
WorldView's products will be the National Geospatial-Intelligence Agency. The
government awarded a contract to DigitalGlobe four years ago in excess of $500
million to help launch the next-generation satellite.
"They
have areas on the ground they like us to image. We image them and send over the
imagery," Herring said. "It is not as though all of the imagery that
we take goes to them. They have the ability to request areas that we will
image...They're also able to purchase from the library as well."
The demand for data from
the relatively young commercial Earth-imaging business is soaring, officials
say, as customers learn new ways to use the information.
"What we're really
seeing is because of the availability...the applications are growing
exponentially," Herring said.
State and local governments
use the imagery to keep tabs on urban growth, real estate developers can assess
building plans, insurance companies map out areas threatened by a high wildfire
risk and scientists can study environmental changes.
"At the beginning of
our operations, people would call and they wanted to track animals - herd of
elephants - because of the resolution they could see elephants. What we are
finding is it's less about understanding the individual animals and more about
understanding the environment in which they live and mapping it out, doing
change detection," Herring said.
"It's mapping the
ecosystem, then keeping an up-to-date view of that ecosystem, understanding the
human and environmental impacts that are occurring in those ecosystems, if they
put in a new walking path, there's deforesting going on or drought, how does it
impact the ecosystem."
DigitalGlobe's QuickBird is
expected to operate for another two years, and the new WorldView 1 has a life
expectancy of about seven-and-a-half-years. Builder of those two satellites,
Ball Aerospace, is constructing the WorldView 2 craft for launch perhaps by the
end of 2008. It could fly aboard one of the remaining yet-unsold Delta 2
rockets.
Continuing to grow the
commercial imagery market will require more satellites, enabling the companies
to keep their picture supply as fresh as possible and expand the regions
covered with high-resolution photos.
"The industry needs to
get more satellites up to address people's wish to not only update on a regular
basis but paint the globe," Herring said.
"From a global mapping
standpoint, we haven't even really started to address less populated areas, let
alone rural areas."
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