A company that scans the world with its high-resolution imaging satellites launched another spacecraft Thursday, one that promises to reveal Earth's true colors for commercial mapping and monitoring.

Read our launch story.

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VIDEO: DELTA ROCKET LAUNCHES WORLDVIEW 2 PLAY
VIDEO: LAUNCH PAD GANTRY ROLLED BACK FROM ROCKET PLAY
VIDEO: NARRATED PREVIEW OF WORLDVIEW 2'S LAUNCH PLAY
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Another collection of launch photos taken by sound-activated cameras at the pad can be seen here.

Following release of the WorldView 2 spacecraft from the Delta 2 rocket today, a DigitalGlobe ground station received communications from the satellite confirming a successful separation from its launch vehicle and the automatic initialized its onboard processors, the company says.

"The successful launch of WorldView 2 is an important milestone for the industry and for DigitalGlobe," said Jill Smith, chairman and chief executive officer of DigitalGlobe. "Once commissioned, WorldView 2 will effectively double DigitalGlobe's collection capacity, enabling us to provide at least annually updated coverage of the world as well as intra-day revisit for more rapid and reliable collection for our customers. Additionally, WorldView 2's eight spectral bands will significantly enhance our ability to meet our customers' needs for feature identification, change, detection, and other high-value services."

It was a beautiful blastoff for the Delta 2 rocket from California today, just after low clouds and fog moved away. A collection of launch photos taken from the press viewing site can be seen here.

"The Delta 2 is one of my favorite rockets; I've been launching them since I was a lieutenant colonel," Col. Buck said. "I'm very confident whenever I am working with this rocket, but I am even more confident when I work with this team."

"There really is nothing quite as exciting as seeing one of these powerful little rockets jump off the pad," said Col. David Buck, the 30th Space Wing commander at Vandenberg and the launch decision authority today.

"I'm incredibly proud of this wing and its mission partners for the way they conquer the immense technical difficulties of space lift operations and make it look so easy."

This is the 91st consecutive successful Delta 2 rocket launch dating back to May 1997. The Delta 2's overall history since debuting in 1989 has achieved 144 successes in 146 flights.

"Delta 2 has achieved a launch success record of nearly 99 percent, which is an incredible achievement and we are extremely proud to provide reliable and cost-effective launch services for our customers," said Jim Sponnick, United Launch Alliance vice president, Delta Product Line.

The next Delta 2 rocket launch will occur from Vandenberg Air Force Base on December 7 at 6:10 a.m. local time. That mission will deploy NASA's Wide-field Infrared Survey Explorer space observatory.

Our archive of Delta rocket coverage can be viewed here.

"Congratulations to both DigitalGlobe and Boeing Launch Services for this tremendous launch success," said Jim Sponnick, United Launch Alliance vice president, Delta Product Line. "ULA appreciates the confidence that DigitalGlobe has shown in our Delta team by launching WorldView 2 and two prior missions on Delta 2 rockets."

T+plus 61 minutes, 52 seconds. SPACECRAFT SEPARATION! The WorldView 2 commercial Earth-imaging spacecraft has been released from the Delta 2 rocket's second stage, completing today's launch!

The high-resolution imager will provide new views of the world and capture the planet in its truest natural color for government and civil users.

T+plus 60 minutes, 45 seconds. The second stage is entering the planned nine-degree per second spin in preparation for releasing the WorldView 2 spacecraft to fly on its own.

T+plus 60 minutes, 20 seconds. Pitch, yaw and roll rates have gone to zero following the maneuver to the deploy attitude.

T+plus 60 minutes. Deployment of WorldView 2 is about two minutes away.

T+plus 59 minutes. The orbit achieved following this latest burn by the second stage is right on the mark.

T+plus 57 minutes. At this point in the flight, the rocket is maneuvering itself to the proper orientation for release of the payload.

T+plus 54 minutes. The second stage engine has performed its approximate 22-second firing to propel spacecraft payload into the desired orbit.

T+plus 53 minutes, 38 seconds. Ignition confirmed! WorldView is heading to its desired orbital perch.

T+plus 52 minutes, 20 seconds. Malindi has acquired the rocket's signal.

T+plus 51 minutes. The next firing by the Delta rocket's second stage is coming up in just under three minutes. The Malindi tracking station in Kenya should acquire the rocket's signal momentarily as it flies northbound toward Africa.

T+plus 45 minutes. Maps illustrating the rocket's flight carrying the WorldView 2 satellite can be viewed here.

T+plus 40 minutes. The unique feature of the WorldView 2 satellite is its ability to image the planet in eight different color bands, which is twice as many as previous spacecraft of this type. So how will the colors benefit users? Here's what a company spokesperson says:

"First of all, it will represent the Earth in its truest natural color. The additional bands together with the traditional satellite bands more closely represent the world as would the human eye.

"Overall, the image detail from WorldView 2 improves the identification of more of the Earth's features, both man-made and natural, and provides more confidence in the classification of those objects. A good example is vegetation analysis. Today, with four-band multispectral imagery you are able to determine land that contains coniferous forest but WorldView 2 is expected to be able to determine the exact makeup of that forest by identifying down to the species level (e.g., pine, flatwood, longleaf pine, etc.) It will also be able to identify the condition of vegetation such as health and age.

"Not only will these bands help with vegetation but it will also allow for improved classification of man-made structures such as building, roads and infrastructure. With the increased level of detail, there any many uses such as helping to improve the understanding of global warming on sustainable land and resources, tracking the impact of pollution, improving natural resource management and exploration, and protecting and monitoring agricultural development and sustainability.

"With over 500 million square kilometers of new capacity, DigitalGlobe is able to deploy this capacity in numerous new ways with predictable, scheduled collections of major metropolis and key urban areas for digital mapping and location based services, large-scale regional coverage for base mapping and change detection references.

"WorldView 2 will also have a coastal blue band which aids in bathymetry but also helps in atmospheric corrections.

"Apart from the eight-band uses, the real-world uses of WorldView 2 will focus on wide-scale mapping and analysis that hasn't readily been available before."

T+plus 34 minutes. A review of data collected aboard the tracking aircraft confirms the rocket reached the planned preliminary orbit.

T+plus 25 minutes. The official liftoff time was 11:51:00.256 a.m. PDT.

T+plus 20 minutes. The rocket is coasting until the second stage restarts its engine at T+plus 53 minutes, 34 seconds for a brief 22-second firing to put the vehicle into a near-circular sun-synchronous orbit above Earth. Deployment of WorldView 2 from the launch vehicle is expected to be confirmed nearly 62 minutes after liftoff.

T+plus 17 minutes. Shortly after the rocket rocket enters this temporary orbit, it maneuvers itself into the proper orientation for the coast and begins a slow rolling motion to keep the thermal conditions even across the vehicle.

At T+plus 45 minutes, 20 seconds, the second stage will begin another maneuver get into the correct position for the next engine firing.

T+plus 12 minutes, 30 seconds. The rocket is flying out of view from the tracking plane. The next communications from Delta is expected in about 40 minutes when it rises in the skies over the Malindi station in Kenya.

T+plus 11 minutes, 8 seconds. SECO 1 has been confirmed from the instrumented tracking aircraft. The second stage's Aerojet-made engine completed its initial burn for the launch. Delta and WorldView should be in that preliminary parking orbit.

T+plus 9 minutes. About two minutes remain in this burn of the second stage engine to achieve the intended parking orbit. The targeted orbit should be 435 nautical miles at apogee, 106 miles at perigee and inclined 98.6 degrees.

T+plus 8 minutes. The Delta rocket rocket has flown out of range from the ground tracking station network. An instrumented aircraft positioned over the Pacific will acquire the rocket's telemetry signal as the Delta travels away from Vandenberg.

The mobile assets get outfitted with equipment needed to receive the stream of data from the Delta 2's second stage after the rocket flies beyond the horizon of Vandenberg's ground station and reaches a preliminary parking orbit around the planet.

T+plus 7 minutes, 5 seconds. The Delta 2 rocket is 99.8 miles in altitude, 671 miles downrange and traveling at 13,237 mph.

T+plus 6 minutes, 20 seconds. The second stage is firing normally as the rocket passes 93 miles in altitude.

T+plus 5 minutes, 40 seconds.The Delta 2 rocket is 83.5 miles in altitude, 425 miles downrange and traveling at 12,355 mph.

T+plus 5 minutes, 12 seconds. The Delta 2 rocket is 75 miles in altitude, 338 miles downrange and traveling at 12,080 mph.

T+plus 4 minutes, 50 seconds. The rocket's 10-foot-diameter nose cone enclosing the WorldView 2 spacecraft has been shed. The fairing is no longer needed, now that the Delta has climbed above the atmosphere.

T+plus 4 minutes, 41 seconds. The Delta's second stage engine has ignited!

T+plus 4 minutes, 38 seconds. MECO and staging confirmed. The first stage main engine cutoff, followed moments later by shutdown of the twin vernier steering thrusters. The spent stage then jettisoned.

T+plus 3 minutes, 45 seconds. The Delta 2 rocket is 49.1 miles in altitude, 126.7 miles downrange and traveling at 7,877 mph.

T+plus 3 minutes, 30 seconds. The first stage main engine still firing well. The Pratt & Whitney Rocketdyne powerplant consumes kerosene fuel and liquid oxygen to produce about 200,000 pounds of thrust.

T+plus 2 minutes, 45 seconds. The Delta 2 rocket is 34.2 miles in altitude, 42.5 miles downrange and traveling at 4,675 mph.

T+plus 2 minutes, 22 seconds. The trio of ATK-made solid rocket boosters ignited inflight have burned out of propellant and separated. The Delta 2's first stage RS-27A main engine will be providing the sole thrust for the next few minutes.

T+plus 1 minute, 39 seconds. The ground-lit boosters have jettisoned from the first stage. They remained attached until the rocket cleared off-shore oil rigs.

T+plus 1 minute, 12 seconds. All six ground-start solid rocket boosters have burned out and the three air-lit motors were just lit.

T+plus 50 seconds. The rocket has flown through the area of maximum aerodynamic pressure in the lower atmosphere. Coming up on ignition of the remaining three strap-on boosters.

T+plus 35 seconds. Delta has broken the sound barrier, rapidly accelerating on the power of its first stage main engine and the six ground-lit strap-on solid-fuel boosters.

T+plus 15 seconds. The launch vehicle is departing Vandenberg Air Force Base along an initial flight azimuth of 196 degrees, heading south for the trek downrange over the Pacific.

LIFTOFF! Liftoff of the Delta 2 rocket boosting to orbit WorldView 2, a commercial imaging satellite to see the true colors of planet Earth!

T-minus 30 seconds. SRB ignitors will be armed at T-minus 11 seconds.

The launch ignition sequence will begin at T-minus 2 seconds when a launch team member triggers the engine start switch. The process begins with ignition of the two vernier thrusters and first stage main engine start. The six ground-lit solid rocket motors then light at T-0 for liftoff.

T-minus 1 minute. All remains "go" for today's launch of a new satellite to view the world.

T-minus 75 seconds. First stage liquid oxygen topping to 100 percent is underway.

T-minus 1 minute, 45 seconds. The launch pad water suppression system is being activated.

T-minus 2 minutes. The first stage liquid oxygen vents are now being closed so the LOX tank can be pressurized for launch. Puffs of vapor from a relief valve on the rocket will be seen in the remainder of the countdown as the tank pressure stabilizes.

T-minus 2 minutes, 30 seconds. The WorldView 2 spacecraft has been declared "go" for launch.

T-minus 2 minutes, 45 seconds. Vehicle ordnance is being armed.

T-minus 3 minutes and counting towards liftoff of Delta 345.

T-minus 3 minutes, 45 seconds. The Delta 2 rocket's systems are now transferring to internal power for launch. And the launch pad water system is being enabled.

T-minus 4 minutes and counting! Clocks are ticking through the final segment of the Delta 2 rocket's countdown to liftoff. Launch is set for 11:51 a.m. local time from Vandenberg Air Force Base, California.

Following liftoff, the vehicle will head southward as it climbs into orbit on a 62-minute flight to deploy its satellite payload.

Now five minutes from launch! The "go" has been announced to resume the countdown for 11:51 a.m. PDT liftoff.

The launch team and management team members who had not yet voiced "go" status during the earlier poll have now given their approvals to proceed.

NEW LAUNCH TIME. Liftoff is being retargeted for 11:51 a.m. local time (2:51 p.m. EDT; 1851 GMT).

The issue under discussion involves a battery on the second stage, a United Launch Alliance spokesman says.

The launch team is working to confirm all is in readiness to proceed into the last four minutes of the count. A new liftoff time has not yet been established.

Hold extended. Countdown will continue to hold at T-minus 4 minutes.

The WorldView 2 spacecraft has been configured for launch.

Final instructions are being read to the launch team. A final "go/no go" call whether to resume the countdown will be made shortly.

Launch team polling is underway to verify the rocket, payload, ground systems and weather are ready for liftoff.

Putting WorldView 2 into orbit will expand operator DigitalGloble's constellation of high-resolution commercial imagery satellites, joining the QuickBird spacecraft launched in 2001 and WorldView 1 deployed in 2007.

At the moment of today's 11:38 a.m. launch by the Delta 2 rocket, QuickBird will be orbiting 243 nautical miles over the equatorial Indian Ocean and WorldView 1 will be flying 272 nautical miles over northern Canada on a southerly trajectory that passes east of Vandenberg some 10 minutes after the scheduled liftoff time.

T-minus 4 minutes and holding. The countdown has entered the final planned built-in hold. This is a scheduled 10-minute pause leading to today's liftoff at 11:38 a.m. local time (2:38 p.m. EDT; 1838 GMT).

Now just 20 minutes away from liftoff time.

WorldView 2 will become the 221st primary payload put into space by the venerable Delta 2 rocket over the past 20 years. Here's a look at some other stats about today's mission. This will be:

The 345th Delta rocket launch since 1960

The 9th Delta of 2009

The 146th Delta 2 rocket mission since 1989

The 6th commercial Delta 2 conducted by ULA for Boeing Launch Services

The 37th Delta 2 rocket launch from Vandenberg AFB

T-minus 15 minutes and counting. Countdown clocks are running again following the planned 20-minute hold. The count will continue to the T-minus 4 minute mark where another planned hold is scheduled. Launch remains set to occur at 11:38 a.m. local time (2:38 p.m. EDT; 1838 GMT).

A readiness poll of the launch team has resulted in a "go" to restart the countdown as scheduled.

The Delta rocket will be flying in its configuration known as the 7920-10 vehicle. The two-stage launcher is fitted with nine strap-on solid-propellant motors and a 10-foot diameter composite nose cone.

Flying away from its coastal pad, the rocket will head southward over the Pacific Ocean. Six of the solid boosters are ignited on the ground, the other three light a minute into flight to give the Delta's first stage added thrust through the initial ascent. Once the solids burn out and separate, the kerosene-powered main engine will continue pushing the rocket to an altitude of 65 nautical miles.

The spent first stage will jettison to let the hydrazine-fueled second stage ignite and achieve a preliminary parking orbit 11 minutes into flight.

The rocket then settles into a quiet coast along a trajectory the cruises above the South Pacific before crossing Antarctica and proceeding northbound toward Africa. The second stage reignites its engine for 22 seconds off the western coast of Madagascar to reach a near-circular polar orbit above the planet.

The WorldView 2 spacecraft is expected to be released from the rocket 62 minutes after blastoff.

T-minus 15 minutes and holding. Clocks have entered the next planned hold period during the Terminal Countdown. This pause will last 20 minutes in duration.

These holds are designed to give the launch team a chance to deal with any problems and catch up on work that could be running behind schedule.

A reminder that if you will be away from your computer but would like to receive occasional updates on the countdown, sign up for our Twitter feed to get text message updates on your cellphone. U.S. readers can also sign up from their phone by texting "follow spaceflightnow" to 40404. (Standard text messaging charges apply.)

The first stage engine steering checks just finished.

The second stage engine slews are complete. First stage tests have begun.

The launch team is beginning the "slew" or steering checks of the first and second stage engines. These are gimbal tests of the nozzles on the first stage main engine and twin vernier engines and second stage engine to ensure the rocket will be able to steer itself during launch.

The countdown is entering the final hour until the Delta 2 rocket soars away from the central coast of California carrying the WorldView 2 spacecraft.

As its name suggests, WorldView 2 follows a sister-satellite also built by Ball Aerospace and launched atop a Delta 2 rocket in 2007. So how is this new spacecraft different? Here's what a company spokesperson says:

"WorldView 2 builds upon many of the technical capabilities of WorldView 1, which was the first high-resolution satellite to operate with Control Motion Gyros, and provides very high agility with large scale collection capabilities and fast point tracking. We've taken those same technical features and added four-multispectral bands to improve the spectral fidelity and natural color capabilities. At this time, there isn't another satellite which combines high resolution with eight-bands and the level of agility that we get from the WorldView-class satellite."

The launch team is monitoring the wind conditions aloft. Weather balloon data shows winds are a possible concern for vehicle controls up through 20,000 feet. But there's still more balloon runs planned to relay data today. The countdown is marching onwards in hopes the winds will cooperate.

Loading of the Delta 2 rocket's first stage liquid oxygen tank has been accomplished. The process took 26 minutes and 4 seconds today, concluding at 10:20:19 a.m. local time. The tank will be replenished through the countdown to replace the super-cold liquid oxygen that naturally boils away.

The rocket is now fully fueled for launch. The vehicle's first stage was successfully loaded with RP-1 kerosene fuel a little while ago. The second stage was filled with its storable nitrogen tetroxide and Aerozine 50 fuels last Friday. And the nine strap-on booster rockets are solid-propellant.

The liquid oxygen tank has reached the 95 percent mark.

Liquid oxygen loading is continuing. Once the first stage tank is 95 percent full, the "rapid load" valve will be closed and the slower "fine load" phase will continue to fill the rocket.

Now just 90 minutes away from the planned launch of the Delta 2 rocket.

This approximate 25-minute process to fill the first stage liquid oxygen tank has been underway for 10 minutes. As the super-cold liquid oxygen continues to flow into the first stage, a bright white plume of vapors begins streaming from a vent on the rocket and the bottom of the vehicle ices over.

LOX loading begins. Cryogenic liquid oxygen, chilled to Minus-298 degrees F, has started flowing from a 28,000-gallon storage tank at Space Launch Complex 2, through plumbing and into the bottom of the Delta 2 rocket. The LOX will be consumed by the first stage main engine during the first four-and-a-half minutes of flight along with the 10,000 gallons of RP-1 kerosene already loaded aboard the vehicle.

The launch team has received the official "go" to begin preparations for loading the rocket's first stage liquid oxygen tank as planned.

The countdown is continuing as planned at Vandenberg Air Force Base for launch just two hours from now at 11:38 a.m. local time (2:38 p.m. EDT; 1838 GMT).

The Delta 2 rocket will place into orbit the WorldView 2 satellite, the latest high-resolution commercial Earth-imaging spacecraft for operator DigitalGlobe of Longmont, Colorado.

How will the addition of this new satellite help DigitalGlobe win new customers? Here's what a company spokesperson says:

"Having faster delivery times obviously provides competitive advantages, but the amount of new capacity allows us to create more opportunities to serve the growing use of imagery in location-based services and mobile applications.

"Large-scale infusion of fresh, up-to-date imagery broadens the appeal for satellite imagery in emerging commercial applications as well as creating increased value for the sophisticated, professional users who will take advantage of the higher detail and definition from eight-band multispectral capabilities."

The latest weather outlook for launch time is calling overcast skies at 400 feet with low status clouds and mist, visibility of six miles, a temperature in the mid 50s F and northwesterly winds 12 to 18 knots. All of those conditions are within limits for liftoff.

Work to turn on and configure the Delta's onboard guidance computer has been completed.

The first stage fuel tank of the Delta 2 rocket has been fully loaded for today's planned launch. The tank was filled with a highly refined kerosene, called RP-1, during a 17-minute, 50-second process that officially concluded at 9:21:03 a.m. local time.

The next major task in the count will be loading supercold cryogenic liquid oxygen into the first stage starting in about 30 minutes.

The kerosene and liquid oxygen will be consumed by the stage's Pratt & Whitney Rocketdyne RS-27A main engine and twin vernier steering thrusters during the initial four-and-a-half minutes of flight.

Rapid-loading of the RP-1 tank has concluded with 9,800 gallons already aboard the rocket. Fine load is continuing to finish filling the tank.

The launch team has computed that today's full load for the first stage fuel tank is 9,979 gallons.

Once the tank is filled to 98 percent or 9,800 gallons, the "rapid load" valve will be closed and the slower "fine load" phase will continue to top off the tank.

About seven minutes into the fueling process. The rocket's kerosene tank has been filled with 4,000 gallons so far.

Fueling begins. About 10,000 gallons of the kerosene propellant are pumping into the base of the rocket from storage tanks at the pad as fueling of the Delta 2's first stage begins for today's launch.

A reminder that if you will be away from your computer but would like to receive occasional updates on the countdown, sign up for our Twitter feed to get text message updates on your cellphone. U.S. readers can also sign up from their phone by texting "follow spaceflightnow" to 40404. (Standard text messaging charges apply.)

First stage fueling preparations are starting. After verifying valves, sensors, flow meters and equipment are ready, a highly-refined kerosene fuel will begin flowing into the vehicle a few minutes from now.

The rocket's control system and guidance computer are being turned on.

And the launch is starting the steps to pressurize the first and second stage helium and nitrogen systems and the second stage fuel and oxidizer tanks.

Countdown begins! The three-hour Terminal Countdown sequence has been initiated for today's launch of the Delta 2 rocket from Vandenberg Air Force Base in California. The booster will carry into orbit the latest commercial satellite to view the world.

Liftoff from the Space Launch Complex 2 pad is scheduled for 11:38 a.m. local time (2:38 p.m. EDT; 1838 GMT). Today's available launch window stretches 14 minutes to 11:52 a.m.

Between now and the launch time, the rocket's guidance system will be activated, onboard helium and nitrogen tanks brought up to pressure, the kerosene and liquid oxygen supplies loaded into the first stage, checks performed on the safety system and steering tests conducted on the engines.

This is a normal countdown for the Delta 2, a typical timeline to ready the vehicle for flight. Pre-planned holds are built into the countdown at the T-minus 15 and T-minus 4 minute points. The first will last 20 minutes; the second will be 10 minutes in length. Those pauses are designed to give the launch team the opportunity to work problems or catch up on items perhaps running behind schedule.

Polls of the various launch team members and managers occur during that T-minus 4 minute hold to ensure everything is ready to proceed into the busy final minutes that see the rocket put on internal power, pressurized and armed for liftoff from California's Central Coast.

The launch conductor has just polled his team to ensure all stations are manned and systems are set for the Terminal Countdown.

"Man stations for Terminal Count." The launch team members are about to be polled confirm their readiness to enter into the countdown.

Workers have finished their hands-on chores at the launch pad and cleared the area for the rest of today's countdown.

T-minus 150 minutes and holding. Clocks have been paused for a planned 60-minute built-in hold. The Terminal Countdown remains scheduled to start at 8:38 a.m. local time (11:38 a.m. EDT; 1538 GMT), beginning the formal three-hour process to bring the rocket to life for its commercial mission.

A beautiful collection of photos taken at the launch pad showing the Delta 2 rocket poised for today's launch can be seen here.

The pad's service gantry was wheeled away from the Delta 2 rocket overnight at Vandenberg Air Force Base's Space Launch Complex 2.

The 177-foot tall mobile service tower was used to stack the two-stage vehicle, the nine strap-on solid rocket motors and the WorldView 2 payload atop the pad's launch mount. The tower also provided the primary weather protection and worker access to the rocket during its stay at the oceanside complex on North Vandenberg.

"I think this is probably one of the smoothest launch campaigns we have had," Hieu Lam, the Delta commercial program manager, said in an interview yesterday. "We've had hardly any launch vehicle issues, very few compared to previous missions, the satellite had no issues at all during their processing time. It's beautiful."

Ground teams will spend the next couple of hours getting the pad secured in advance of the Terminal Countdown. Launch remains targeted for 11:38 a.m. local time (2:38 p.m. EDT; 1838 GMT).

A commercial Earth-imaging satellite built to see the planet's true colors for high-resolution mapping and monitoring will ascend to orbit Thursday atop a Delta 2 rocket launched from California's Vandenberg Air Force Base.

Officials from rocket-maker United Launch Alliance, satellite operator DigitalGlobe and builder Ball Aerospace, the commercial launch marketer Boeing and all of the supporting cast gathered for the final readiness meeting this morning and approved plans to enter into the countdown tonight.

"Everything is looking good," said Hieu Lam, the Delta commercial program manager.

"There are no issues coming out of the (Launch Readiness Review). We are working no issues on the launch vehicle, the Range is green, the satellite is good."

Liftoff from the Space Launch Complex 2 pad is scheduled for 11:38 a.m. local time (2:38 p.m. EDT; 1838 GMT), which is the opening of a 14-minute window of opportunity for the rocket to fly.

Weather forecasters say there is no chance that conditions will violate any of the launch rules. The rare 100 percent "go" outlook includes just a few low clouds with light fog and haze, five miles of visibility, northwesterly winds of 12 to 16 knots and a temperature of 55 to 58 degrees F.

"A dry upper-level low system currently over Vandenberg will move east of base this evening. High pressure will build over the western U.S. behind the exiting low. This high pressure system will remain overhead into tomorrow and will bring fair weather conditions," launch forecasters say.

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The launch will deploy WorldView 2, a sharp-eyed orbiter that can see objects just 18 inches across from 415 nautical miles up. The craft will join two others controlled by DigitalGlobe of Longmont, Colorado. The QuickBird and WorldView 1 satellites were launched aboard Delta 2 rockets for the company in 2001 and 2007, respectively.

"With the addition of WorldView 2, an impressive third component of our constellation, DigitalGlobe will have increased capacity, which is expected to improve the speed with which we deliver our imagery products to our customers and provide more frequent refresh of our ImageLibrary to support a range of monitoring, analysis and decision-making services," said Jill Smith, chairman and chief executive officer of DigitalGlobe.

"The combination of rapid, comprehensive imagery collection; an industry-leading ImageLibrary; and fast and flexible worldwide content delivery allow DigitalGlobe products to integrate seamlessly into any mapping or enterprise solution, including hosting services, Web services and mobile applications."

What's special about WorldView 2 is the capability to image in eight different color bands. The result will be images of Earth in its truest natural colors.

"At this time, there isn't another satellite which combines high-resolution with eight bands and the level of agility that we get from the WorldView-class satellite," DigitalGlobe says.

Commercial imaging satellites have a range of customers, including the U.S. government for intelligence-gathering, as well as urban planners, real estate developers, environmental interests and supplying pictures to online sites like Google Earth.

DigitalGlobe's main rival in the U.S. is the GeoEye company, which launched its latest satellite atop a Delta 2 rocket a year ago.

Thursday's launch will take about 62 minutes from liftoff until release of WorldView 2 into its polar orbit. Post-launch calibration and accuracy tests are planned to verify the satellite's performance before it enters service for a mission designed to last at least 7 years.

"We expect that WorldView 2 imagery products will be commercially available approximately 90 days after its successful launch," DigitalGlobe says.

"It will give us nearly twice our current collection capacity, it will allow us to collect nearly three times the Earth's land mass; it will give us unique refresh and coverage," the company says.

"Large-scale infusion of fresh, up-to-date imagery broadens the appeal for satellite imagery in emerging commercial applications as well as creating increased value for the sophisticated, professional users who will take advantage of the higher detail and definition from eight-band multispectral capabilities."

We will have complete live updates throughout the countdown and climb to orbit. Watch this page for the latest!

A Delta 2 rocket powered two experimental missile-tracking satellites into orbit today to test advanced technologies for the nation's defense against enemy attacks.

Read our full story.

We have posted two photo gallerys here and here.

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Additional coverage for subscribers:
VIDEO: THE FULL LAUNCH EXPERIENCE PLAY
VIDEO: DELTA 2 ROCKET LAUNCHES STSS DEMO PLAY | HI-DEF
VIDEO: STSS DEMO SATELLITES DEPLOYED PLAY
VIDEO: POST-LAUNCH BRIEFING WITH NASA AND MDA PLAY

VIDEO: LAUNCH REPLAYS: CAPE CANAVERAL BEACH PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: WIDE VIEW FROM PRESS SITE PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: TIGHT SHOT FROM PRESS SITE PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: KSC DOAMS TRACKER PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: UCS 23 TRACKER PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: PAD CAMERA NORTHEAST PLAY
VIDEO: LAUNCH REPLAYS: PAD CAMERA SOUTHWEST PLAY
VIDEO: LAUNCH REPLAYS: PAD CAMERA WEST PLAY

VIDEO: NARRATED REVIEW OF STSS DEMO PREPS PLAY | HI-DEF
VIDEO: NARRATED REVIEW OF DELTA 2'S PREPARATIONS PLAY | HI-DEF
VIDEO: PAD TOWER ROLLS BACK AROUND DELTA 2 AFTER SCRUB PLAY
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