The nation's new weather observatory successfully completed a series of altitude raising maneuvers to reach geostationary orbit early Wednesday, just 10 days after its launch from Cape Canaveral aboard a Delta 4 rocket.

The craft is the latest weather satellite designed to fly 22,300 miles above the planet and constantly track conditions for meteorologists from orbital vantage points over the eastern and western sides of the Americas.

The Geostationary Operational Environmental Satellite was built and launched under the name of GOES O. But following NOAA tradition of renaming its satellites upon reaching orbit, the craft became GOES 14 on Wednesday morning.

Some five firings of the satellite's liquid-fueled engine circularized the orbit after being deployed by the Delta 4 rocket in an elliptical transfer orbit. The craft's current position is above the equator at 89.5 degrees West longitude.

The power-generating solar array will be unfurled Thursday. Handover of control from satellite-maker Boeing to NASA is scheduled in the coming days.

The space agency plans months of instrument activation work and extensive testing that's expected to last through December. If all goes well, GOES 14 will be given to NOAA for use in the network of weather-watching satellites.

"Reliable satellite coverage helps us see severe weather as it develops," said Mary E. Kicza, assistant administrator for NOAA's Satellite and Information Service. "With more than a thousand tornadoes touching down in the United States each year, and hurricanes a serious risk to residents along the Gulf and East coastlines, it's critical (GOES 14) is in orbit and ready when needed."

"The imagery and data we get from GOES is key to our ability to continuously monitor and diagnose weather in the tropics," said Bill Read, director of NOAA's National Hurricane Center in Miami. "Continued improvements in the type and quality of GOES data will contribute to improvements in tropical cyclone forecasts."

Running a day late because of stormy weather, a United Launch Alliance Delta 4 rocket boosted a new GOES weather satellite into space Saturday to serve as an orbital spare for the National Oceanic and Atmospheric Administration's fleet of hurricane-tracking weather sentinels.

Read our full story.

The launch photo gallery is posted here.

Additional coverage for subscribers:
VIDEO: THE FULL LAUNCH EXPERIENCE PLAY
VIDEO: DELTA 4 BLASTS OFF WITH GOES O PLAY

VIDEO: LAUNCH REPLAYS: PAD 39A CAMERA PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: SHUTTLE ENDEAVOUR PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: CAUSEWAY ZOOMED VIEW PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: CAUSEWAY WIDE-ANGLE VIEW PLAY | HI-DEF
VIDEO: LAUNCH REPLAYS: UMBILICALS RETRACT PLAY
VIDEO: LAUNCH REPLAYS: CAMERA IN FRONT OF PAD PLAY
VIDEO: LAUNCH REPLAYS: UCS 23 TRACKING CAMERA PLAY
VIDEO: LAUNCH REPLAYS: PLAYALINDA BEACH TRACKER PLAY
MORE: DELTA/GOES O VIDEO COVERAGE
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"ULA congratulates Boeing and its NASA and NOAA customers for the successful launch of GOES O," said Jim Sponnick, United Launch Alliance's vice president, Delta Product Line.

"Millions of people a year are adversely affected by weather ranging from localized thunderstorms to tornados and hurricanes. GOES O will significantly improve the data collection scientists need to learn more about our planet's weather and will better prepare people all over the world for significant weather events."

T+plus 4 hours, 21 minutes. SPACECRAFT SEPARATION! The Geostationary Operational Environmental Satellite O has been deployed into orbit from the Delta 4 rocket's upper stage, completing tonight's successful launch.

The 7,000-pound spacecraft, built by Boeing, is a next generation weather satellite that will be ready to replace one of the nation's older observatories in the coming years.

"It's going to guarantee the availability of state-of-the-art satellite data for the next decade, and we really look forward to it," said Joe Schaefer, director of NOAA's Storm Prediction Center.

The craft will spend the next 12 days performing planned orbital circularization burns to reach geostationary orbit 22,300 statute miles above the planet. It will be parked at 90 degrees West longitude over the equator for testing.

Boeing controls the initial operations of the satellite. In fact, the company was responsible for the launch services too. After unfolding the solar array and appendages, plus completion of early testing around July 18, NASA will begin six months of rigorous checkout.

"At the end of that six months, NASA takes contractual control of the spacecraft," said Steve Kirkner, GOES project manager at NASA.

"Assuming there is no further resolution of any anomalies during the post-launch tests, the spacecraft then will be turned over to NOAA."

It'll be relocated to orbital storage around 105 degrees West.

"With the new capabilities of the GOES O (satellite), we really look forward to improvements in what we can do," said Joe Schaefer, director of NOAA's Storm Prediction Center.

GOES O is the second of three in the current series with sharper vision and longer life.

"Let's face it, these are probably about the most sophisticated weather satellites that we actually have," said Andre Dress, GOES O deputy project manager at NASA.

"The things we're looking for, tornadoes and severe thunderstorms are very small in scale. The increased resolution and accuracy that these satellites will present will help us pinpoint what's happening, and if we know what's happening we can do a better job of making short-term and long-term forecasts of where it's going to be," Schaefer said.

Sister-satellite GOES P is scheduled for launch aboard another Delta 4 rocket next year.

T+plus 4 hours, 17 minutes. Spin-up has started in preparation for release of GOES O.

T+plus 4 hours, 12 minutes. Final burn complete! The RL10B-2 motor fired back to life for the third of three burns to send the GOES O spacecraft into the proper orbit.

The upper stage now will perform maneuvers in pitch, yaw and roll to re-orient itself into the attitude for release of the satellite.

T+plus 4 hours. The Delta 4 rocket is using a three-burn ascent profile. It is the fifth time in 10 missions of the Delta 4 family that the upper stage has performed three firings to boost payloads into high orbits.

For the GOES O spacecraft, this upcoming burn will raise the low point of the elliptical geosynchronous transfer orbit and reduce the inclination. With the launch vehicle performing these adjustments, the satellite can preserve its onboard maneuvering fuel for added life.

"It's really a luxury that a lot of satellite programs don't have," said Marty Davis, senior advisor to the GOES project. "The Delta 4, with the two strap-on (SRBs), we get to a better orbit and use less of our fuel. It's really is luxurious compared to years ago."

T+plus 3 hours, 30 minutes. Now 40 minutes away from engine re-start on the second stage. In preparation for that event, the rocket will complete the BBQ thermal roll at T+plus 3 hours, 58 minutes and begin maneuvering itself into the proper orientation for ignition. The burn position should be achieved by T+plus 4 hours, 6 minutes. Then, the stage will start a system chilldown before firing the engine with cryogenic fuel and use its tiny thrusters to settle the propellants in the tanks.

Ignition occurs at T+plus 4 hours, 10 minutes. Spacecraft separation happens at T+plus 4 hours, 21 minutes.

We'll pass along confirmation about the launch events as they become available.

T+plus 2 hours, 24 minutes. The rocket is soaring away from Earth, now more than 11,000 nautical miles above the planet.

The current orbit is an egg-shaped one. Based on the pre-flight plan, the orbit should extend from about 109 nautical miles at its closest point to 18,459 miles at the furthest. The upcoming engine firing at 11:01 p.m. EDT will occur as the rocket nears apogee. The burn lasts just 55 seconds, but will raise the orbit's low point to 3,547 miles, increase the high point to 18,992 miles and reduce inclination closer to the equator.

Deployment of GOES O from rocket to complete the launch is expected at 11:12 p.m. EDT.

To recap, the Delta 4 rocket carrying the GOES O weather satellite launched from Cape Canaveral's Complex 37 at 6:51 p.m. EDT after a 37-minute weather delay.

"The booster conditions indicated that the solids and the Delta 4 (first stage) performed basically right on the money. It was slightly fast at MECO, which is also good because we always try to get as much performance out of the lower stage as possible. So we ended up, I think, about 80 feet per second fast at MECO, and then went through the second stage burn a few seconds longer than the prediction but the orbit was right on the money," says Rich Murphy, director of launch management for the United Launch Alliance's Delta program.

"Then we coasted down to the equator where did our first restart. We had about a four-minute restart of the second stage."

The rocket is now coasting to apogee about 18,000 nautical miles above the Indian Ocean where the third and final burn is planned at T+plus 4 hours and 10 minutes.

T+plus 30 minutes. To see the track the rocket is following this evening, click here.

T+plus 28 minutes. The rocket has just entered a three-hour, 43-minute coast period before the final engine burn to deliver GOES into the desired orbit this evening.

T+plus 27 minutes, 8 seconds. SECO 2. The second of three firings by the upper stage during today's launch has been completed.

T+plus 26 minutes, 5 seconds. About one minute left in this burn by the Delta 4 rocket's upper stage.

T+plus 25 minutes, 55 seconds. The rocket is 111 miles in altitude, 4,976 miles downrange, traveling at 30,684 feet per second.

T+plus 25 minutes, 30 seconds. This burn injects the rocket into a highly elliptical orbit stretching almost 19,000 nautical miles at its furthest point.

T+plus 24 minutes, 30 seconds. This burn will last just over four minutes in duration.

T+plus 24 minutes. Engine performing well.

T+plus 23 minutes, 18 seconds. Good engine chamber pressure reported.

T+plus 23 minutes, 7 seconds. The RL10B-2 engine, fed by liquid hydrogen liquid oxygen, has been reignited to propel GOES O into an intermediate orbit.

T+plus 20 minutes. During this time of the flight, the upper stage maneuvers itself into the proper attitude for engine restart.

T+plus 17 minutes. The vehicle is now in a coast mode before the next firing of the upper stage engine. Ignition of the RL10 engine is now six minutes away.

T+plus 14 minutes. The initial orbit appears right on target with an apogee of 298 miles and perigee of 100 miles, inclined 28 degrees to the equator.

T+plus 12 minutes, 33 seconds. SECO 1. Confirmation that the second stage engine has shut down after the first of three planned firings to inject the GOES spacecraft into geosynchronous transfer orbit.

T+plus 12 minutes. The upper stage's the RL10 engine working well, still firing as planned to reach a low-altitude parking orbit this evening.

T+plus 11 minutes, 5 seconds. The vehicle's steep climb leveled off as it gains speed toward orbtial velocity. Delta is 129 miles in altitude, 1,407 miles downrange from the launch pad.

T+plus 10 minutes, 10 seconds. The RL10 engine is burning a mixture of liquid oxygen and liquid hydrogen cryogenic propellants. Chamber pressures still look good.

T+plus 9 minutes, 30 seconds. The second stage engine continues to fire. This burn will place the vehicle into an initial parking orbit around Earth.

T+plus 8 minutes, 40 seconds. About four minutes remain in this firing of the second stage.

T+plus 7 minutes, 50 seconds. Good controls by the upper stage. Delta is 130 miles in altitude, 812 miles downrange from the launch pad.

T+plus 7 minutes, 10 seconds. Delta is 125 miles in altitude, 691 miles downrange from the launch pad.

T+plus 6 minutes, 35 seconds. Good chamber pressure data being reported from the RL10 engine as it thrusts to reach orbit.

T+plus 5 minutes, 33 seconds. Delta is 102 miles in altitude, 425 miles east of the launch pad.

T+plus 5 minutes, 5 seconds. The protective payload fairing enclosing the GOES satellite atop the rocket has separated.

T+plus 4 minutes, 51 seconds. The cryogenic RL10B-2 upper stage engine has ignited!

T+plus 4 minutes, 35 seconds. The Common Booster Core first stage and the attached interstage have been separated in one piece from the Delta 4's upper stage. The upper stage engine's extendible nozzle is dropping into position.

T+plus 4 minutes, 28 seconds. MECO! Main engine cutoff confirmed as the RS-68 powerplant shuts down.

T+plus 4 minutes, 5 seconds. Delta is 66 miles in altitude, 202 miles east of the launch pad.

T+plus 4 minutes. The RS-68 is consuming nearly a ton of propellants per second as the powerplant pushes the Delta 4 rocket closer to the edge of space.

T+plus 3 minutes. The main engine continues to perform well, consuming its liquid hydrogen and liquid oxygen propellants.

T+plus 3 minutes, 35 seconds. The main engine is throttling down to 57 percent thrust for the rest of its firing in today's launch.

T+plus 2 minutes, 7 seconds. Altitude 23 miles, 25.7 miles downrange.

T+plus 2 minutes. A beautiful launch to begin the life of GOES O.

T+plus 1 minute, 43 seconds. Solid motor separation! The spent boosters have been shed from the first stage. Delta 4 continues powering its way toward space on the thrust generated by the RS-68 main engine.

T+plus 1 minute, 37 seconds. The twin solid rocket boosters have burned out of their propellant. Standing by for jettison.

T+plus 60 seconds. Now passing through the region of maximum aerodynamic pressure.

T+plus 50 seconds. The launcher has broken the sound barrier.

T+plus 30 seconds. The Delta 4 rocket is climbing away from the planet with its main engine firing at full throttle and the two strap-on boosters giving a powerful extra kick.

LIFTOFF! Liftoff of the GOES O observatory and the Delta 4 rocket, launching a new weather satellite for meteorologists across America.

T-minus 12 seconds. Residual hydrogen burnoff ignitors have been fired beneath the main engine.

T-minus 22 seconds. The steering system for the twin solid rocket motor nozzles has been activated.

T-minus 30 seconds. Green board. All systems remain "go" for launch.

T-minus 38 seconds. Upper stage liquid hydrogen tank is confirmed at flight level.

T-minus 1 minute and counting. The ignition conditions for the RS-68 main engine are "go." The terminal countdown sequencer will take control at T-minus 8.5 seconds. Ignition of the RS-68 powerplant will follow at T-minus 5.5 seconds. The engine powers up to the 102 percent level of thrust for a computer-controlled checkout before liftoff.

T-minus 70 seconds. The Air Force-controlled Eastern Range has given its "go" for launch.

T-minus 75 seconds. The liquid hydrogen fuel tank on the upper stage is being secured for launch.

T-minus 80 seconds. Upper stage liquid oxygen tank has been secured at flight level.

T-minus 1 minute, 50 seconds. The first stage liquid hydrogen tank has reached flight level and pressure.

T-minus 2 minutes. The rocket's upper stage liquid oxygen tank is being secured.

T-minus 2 minutes, 40 seconds. The liquid oxygen tank in the first stage is confirmed at the proper level and pressure for flight.

T-minus 3 minutes, 15 seconds. Replenishment of liquid hydrogen and liquid oxygen to the Common Booster Core first stage is being secured in preparation to pressurize the tanks for launch.

T-minus 4 minutes and counting. Ordnance devices aboard the vehicle are being armed.

T-minus 4 minutes, 5 seconds. The systems of the first and second stages of the Delta 4 rocket have switched from ground-fed power to internal batteries for launch.

T-minus 5 minutes and counting! The final phase of today's countdown has commenced for launch of the Delta 4 rocket carrying the GOES O weather observatory. Liftoff is set to occur at 6:51 p.m. EDT (2251 GMT) from pad 37B at Cape Canaveral Air Force Station.

Here's a look at some stats about today's mission. This will be:

• The 342nd Delta rocket launch since 1960
• The sixth Delta of 2009
• The 10th Delta 4 rocket mission since 2002
• The fourth Medium+ 4,2 configuration to fly
• The 8th Delta 4 rocket launch from Cape Canaveral

"What is more exciting than what we're about ready to do, to launch a satellite?" said Andre Dress, GOES O deputy project manager from NASA's Goddard Space Flight Center. "All of the hard work, all of the determination, all of the sweat and time that's been put into this has all culminated into this one event...This is really what it's all about for us."

The launch director has given approval given to resume the count for liftoff at 6:51 p.m.

The launch pad swing arm retraction system pins are being pulled. The three arms will be rotated away from the Delta 4 rocket at liftoff.

The launch team is being polled to ensure systems remain ready.

Weather is go!

The hope is the weather can be declared "go" by 6:45 p.m., leading to resumption of the countdown for a liftoff at 6:51 p.m. EDT.

The launch team continues to wait for the weather to clear.

NEW LAUNCH TIME. Liftoff has been delayed to 6:51 p.m. EDT.

NEW LAUNCH TIME. Liftoff has been retargeted for 6:36 p.m. EDT.

Liftoff will be delayed beyond the 6:24 p.m. target because the weather remains out of limits.

The final readiness polls have been completed and all systems appear to be "go" for liftoff except for the weather.

The ULA launch team and management are guiding the countdown from the Delta Operations Center, located about 9,200 feet from the pad. The engineers overseeing the rocket and ground systems are located on the third floor and the Mission Directors Center room is on the fourth floor. Both rooms have a view of pad 37B and the Delta 4 rocket out their windows. Other rooms are also set up for engineering support.

The DOC was formerly built to support the Titan-Centaur program but was refurbished to support Delta 4.

The weather remains "no go."

The countdown continues to hold at T-minus 5 minutes as the launch team waits out the passage of one thunderstorm cell that's just a little too close for the Delta 4 rocket fly by.

NEW LAUNCH TIME. Liftoff has been pushed back 10 minutes to 6:24 p.m. EDT.

Launch weather officer Joel Tumbiolo confirms that conditions will be "no go" for liftoff at 6:14 p.m. EDT. However, he predicts the thunderstorm clouds and lightning concerns should pass by approximately 6:30 p.m.

The GOES O spacecraft atop the Delta 4 is switching from ground-fed power to its internal batteries for launch.

As expected, clouds associated with that storm to the south have moved within the sensitive zone around the launch pad. So now the launch weather rules for cumulus clouds and lightning are "no go" for liftoff at the current time. Forecasters expect the weather to move out fairly quickly and conditions will be "go" for launch around 6:30 p.m. EDT.

T-minus 5 minutes and holding. The countdown has entered a planned 15-minute hold, but the weather will dictate if additional time needs to be added.

This pause is designed to give the launch team the opportunity to catch up on any work running behind schedule and verify all is in readiness for the final moments of the count. A series of management polls will be conducted during the hold to give approval to proceed with the launch.

Now 30 minutes away from the opening of today's launch window that runs from 6:14 to 7:14 p.m. EDT.

Despite this one thunderstorm south of the launch site, the weather situation is much more optimistic today than the seemingly hopeless conditions experienced just 24 hours ago.

Launch weather officer Joel Tumbiolo says his team is watching a storm cell south of the Cape near the Viera and Melbourne areas. The northern fringe of the cell probably will bring thunderstorm clouds within 10 miles of the launch pad, causing the anvil cloud, cumulus cloud and lightning rules to be "no go" for launch for some period of time.

Tumbiolo says he would expect the weather to clear by around 6:30 p.m. EDT, so there may be some slight delay to the liftoff time today.

T-minus 30 minutes and counting. The countdown is headed to the T-minus 5 minute point where a 15-minute hold is planned. Liftoff is targeted for 6:14 p.m., the opening of today's 60-minute launch window.

The first stage Common Booster Core slews and the commanding tests for the strap-on solid rocket motors have been finished, wrapping up this pre-launch program.

The upper stage engine steering checks have been completed. The first stage tests are next.

Just sixty minutes away from launch and the weather still looks good.

The GOES O weather observatory is the second in a series of three built by Boeing with advances over previous geostationary meteorological spacecraft.

"One of the more important aspects of the newer satellites is we have more operational power during eclipse season, when there is no sun to give us power to the solar arrays, and a 10-year on-orbit lifetime is now required," said Tom Wrublewski, technical acquisitions manager for the GOES project.

"You might wonder why is that important. Some of you might think back several years ago when Hurricane Ivan was getting ready to hit Mississippi at night and we didn't have the ability to do imaging. So now with our improved power performance we can do IR imaging at night and see the hurricanes.

"That's going to be a significant improvement for the GOES N Series and also the GOES O spacecraft."

These updated satellite also have improvements in the imaging and navigation requirements.

"We can locate things at least twice as good as we used to. For example, we could locate a fire within six kilometers, now that's down to three kilometers," he said.

In addition, there's the space environment monitoring suite that looks at the magnetic field and charged particles.

"We've expanded the range of that capability. That's become more important in recent years as we have more polar airplane routes. Due to solar storms that ionosphere disrupts communications, so polar flights have to be cancelled or re-routed, so that's very important to the airline industry. As well as our power industry likes to know when geomagnetic storms will interfere with their power grid transmissions," Wrublewski said.

Besides looking down at Earth's weather, the craft also carry solar X-ray imagers to observe the Sun.

"We're already starting to see some new features that we hadn't seen before on the Sun. For example, we saw, after a severe solar flare, that there was a tsunami-like wave that went across the surface of the Sun, which was rather interesting and a new phenomenon that we hadn't seen before."

GOES O should be checked out and ready to enter orbital storage in mid-December. The craft will await call up for service once one of the older GOES spacecraft is retired in the next couple of years.

"GOES O is going to better ensure that we have continuous coverage in the decade ahead, it's going to improve our imaging, atmospheric sounding, and our near-Earth space weather environmental measurements that are essential to accurate weather and solar forecasts."

The engine steering checks for the RS-68 main engine and RL10 upper stage engine, plus commanding tests with the solid rocket motors is underway.

The RS-68 first stage main engine spin start pressurization operation is starting.

The safety system checks are being performed at this point in the countdown.

The propellant conditioning has been completed on all four cryogenic tanks. The Delta 4 rocket is fueled up and ready for today's launch window to open.

The launch team is entering the last 90 minutes of the countdown. With fueling of the Delta 4 rocket completed, this phase of the count is mostly quiet. Engineers are monitoring systems while the clocks tick down.

In the immediate future, the rocket's safety system will be checked and a series of engine steering tests will occur.

Everything continues to proceed on schedule at Cape Canaveral for liftoff at 6:14 p.m. EDT. And even the weather is looking pretty good right now.

The radio frequency link checks between the rocket and ground have been completed and verified satisfactory.

The thermal insulation inspections have been completed and the rocket remains in good shape following fueling.

You can watch a live video webcast of launch right here on this page. Hit reload on your browser and the video stream will activate. The webcast will play as our text updates automatically refresh for the rest of the countdown and launch.

Liftoff time is just two hours away now.

Upper stage liquid oxygen topping has commenced. That puts all four cryogenic fuel tanks aboard the Delta 4 rocket in topping mode.

Storms that passed over the Cape this afternoon have moved away. The anvil cloud and field mill rules are no longer being violated, and current observed weather conditions are now "go" for launch.

Fingers are crossed that the weather will be cooperative at launch time a little more than two hours from now.

Engineers are conducting the standard evaluation of the Delta 4 rocket's thermal insulation following the loading of supercold propellants into the vehicle.

The weather forecast for today's launch window remains unchanged at a 70 percent chance of "no go" conditions. The outlook predicts shower or thunderstorms in the area, broken decks of clouds at 3,000 12,000 and 25,000 feet, 7 miles of visibility, southwesterly winds of 10-15 knots and a temperature around 83 degrees F.

The topping mode has started for the upper stage's liquid hydrogen tank. The first stage's LOX and LH2 tanks are in topping as well.

The upper stage liquid oxygen filling has been completed. This was the last of the rocket's four cryogenic tanks to loaded today.

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The first stage liquid hydrogen tank is now entering the topping phase.

A current check of the weather shows the lightning and cumulus cloud rules are no longer being violated. But the rules for anvil clouds and the field mills that measure electrical potential remain "no go" for launch.

Also, the Phase 2 lightning advisory that included the pad area has been discontinued.

Now entering the last three hours of the countdown. Fueling of the Delta 4 rocket continues in work for the 6:14 p.m. EDT launch of the GOES O weather satellite from Cape Canaveral, Florida. But will there be a break in the stormy weather to get the rocket airborne during today's 60-minute launch opportunity?

The launch team is not tracking any technical issues with the rocket. Activities continue to run a bit ahead of the timeline.

Fast-fill of the upper stage liquid hydrogen tank has finished. Checks will performed before topping commences.

The chilldown of the second stage liquid oxygen system is reported complete, clearing the way for loading the rocket's tank with 4,500 gallons.

Meanwhile, the stage's liquid hydrogen tank continues to be loaded with 10,000 gallons of propellant for the RL10 engine.

Post-filling tests on the first stage liquid oxygen system are complete. The tank is now entering topping mode. And the "go" has been given for the second stage liquid oxygen chilldown in advance of fueling.

To recap the status of fueling operations, the first stage liquid oxygen tank has been filled and the team is performing vent and relief checks. The first stage liquid hydrogen tank filling just completed and will enter topping mode after its post-loading checks occur. The upper stage liquid hydrogen system is in slow-fill. The upper stage liquid oxygen loading has not yet started.

At pad 37B, winds have been peaking in the mid-20 knots.

The chilldown of the second stage liquid hydrogen system is reported complete, clearing the way for loading the rocket's tank.

A lightning strike about 1.9 miles northeast of the pad.

A powerful storm cell moving across the northern part of the Cape produced a 68-knot wind gust.

Complex 37 has two giant sphere-shaped fuel tanks to store the cryogenic liquid oxygen and liquid hydrogen. The LOX tank holds 250,000 gallons and LH2 sphere about 850,000 gallons. The tanks' large supplies allow for several launch attempts before having to be replenished.

The cryogenics flow from the storage tanks, through pipes to the base of the pad. For the first stage, the propellants are routed up to the launch table upon which the rocket sits. Tail service masts, the large box-like structures at the base of the vehicle, feed the oxygen and hydrogen to the stage in separate umbilicals. The second stage receives its cryos from the middle swing arm that extends from the Fixed Umbilical Tower to the front-side of the rocket.

The launch team has gotten the approval to start chilldown conditioning of the second stage liquid hydrogen system.

The first stage liquid oxygen loading just finished. The tank has been loaded with its supercold oxidizer that is chilled to Minus-298 degrees F. Topping will be completed as the count rolls on.

The countdown activities are running a bit ahead of schedule, the launch conductor says. Filling of the first stage with liquid oxygen and liquid hydrogen is continuing out at launch pad 37B.

No hardware issues with ground equipment, the rocket or payload are being reported. But the weather remains unfavorable at this hour.

The Phase 2 lightning advisory now includes Complex 37 as storm cells pass through the area.

First stage liquid hydrogen tanking operation is switching from "slow-fill" to "fast-fill" mode.

The field mill and anvil cloud rules have gone red on the weather board, joining the lightning and cumulus cloud rules.

First stage liquid oxygen loading continues in progress. The rocket will be loaded with 40,000 gallons of supercold LOX.

The start of liquid hydrogen fueling of the first stage is now confirmed. Some 110,000 gallons of LH2 will fill the rocket's tank.

The cold gas chilldown conditioning of the liquid hydrogen system has been accomplished. Liquid hydrogen propellant will begin to flow into the first stage in "slow-fill" mode. That is sped up to "fast-fill" after a small portion of the tank is loaded.

Chilled to Minus-423 degrees Fahrenheit, the liquid hydrogen will be consumed by the RS-68 main engine along with liquid oxygen during the first four minutes, 27 seconds of the launch.

The hydrogen system's cold gas chilldown conditioning is underway.

The first stage liquid oxygen loading in "slow-fill" mode has commenced.

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The first stage liquid oxygen chilldown is complete. Fueling will begin in the "slow-fill" mode to load a small percentage of the tank. The process then speeds up to the "fast-fill" mode until the tank is nearly full.

A "go" has been given to start the cold gas chilldown conditioning of the first stage liquid hydrogen system.

The launch weather rules for lightning and cumulus clouds have just gone red. A Phase 2 lightning warning for the pad is expected to be issued in about 10 minutes.

Chilldown of the first stage liquid oxygen system has begun. This preps the tank and pumping to guard against shock when the supercold oxidizer begins flowing into the rocket a short time from now.

The launch director has given his formal "go" to press ahead with fueling as planned.

Three back-to-back launch attempts isn't something mission managers are interested in pursuing. So ULA says if the launch does not occur today, the team would stand down Sunday and then reschedule the liftoff for Monday.

T-minus 5 hours, 15 minutes and counting! The Terminal Countdown begins now for today's flight of the United Launch Alliance Delta 4 rocket with the Geostationary Operational Environmental Satellite O.

The countdown has one planned built-in hold at T-minus 5 minutes lasting some 15 minutes, leading to liftoff at 6:14 p.m. EDT (2214 GMT).

The launch pad has been verified evacuated of all personnel in advance of fueling the rocket's two stages this afternoon. Pad systems and equipment stand ready for fueling activities, which should kick off shortly.

There are no technical issues being reported with the rocket or spacecraft. But just like yesterday, the weather will be the driving force today.

Checks of the C-band beacon has been completed. This system is used in tracking the rocket during the flight downrange.

A low-level lightning advisory is about to be issued for the launch site as storms begin to roll closer to the Cape from the west.

The launch team has been polled to verify all consoles are manned and ready to begin the Terminal Countdown when this hold ends at 12:44 p.m. A briefing on countdown procedures is now underway.

"Man stations for Terminal Count."

The latest weather forecast calls for a 70 percent chance of stormy conditions again scrubbing the launch today.

"Similar setup as yesterday. West-southwest flow will result in thunderstorms developing along the west coast sea breeze during the morning and move eastward throughout the day. The strength of the west-southwest winds should once again prohibit an east sea breeze from developing. These thunderstorms will result in several weather launch commit criteria rules to be at risk of violation during the countdown with the Cumulus Cloud Rule and Anvil Cloud Rule being the main concerns. Thunderstorm induced wind gusts are expected to be higher than yesterday," the Air Force weather team reported today.

The specifics for the launch window include low-, mid- and high-level cloud decks, thunderstorms in the vicinity of the launch pad, 7 miles of visibility, southwesterly winds of 10 to 15 knots and a temperature of 82-84 degrees F.

The outlook for Sunday is a 60 percent chance of unfavorable launch weather.

Clocks are holding as planned at the T-minus 5 hour, 15 minute mark. Those clocks around the Cape will begin ticking at 12:44 p.m. EDT to begin the Terminal Countdown sequence that'll lead to the targeted 6:14 p.m. EDT liftoff of the Delta 4 rocket.

The Delta 4 rocket launch team at Cape Canaveral is gearing up for today's countdown. This second attempt to launch the GOES O weather satellite is scheduled for 6:14 p.m. EDT, weather permitting.

Following last night's scrub, the mobile service tower at pad 37B remained in its retracted position. Propellants were drained from the rocket and systems safed for the 24-hour delay.

Today's Terminal Countdown will begin at 12:44 p.m. EDT.

Friday's countdown proceeded without any technical problems. But the weather did not cooperate and officials had to call a scrub late in the launch window.

"For the launch vehicle, everything went very smoothly. Everything was actually ahead of the timetable throughout the count," said Kris Walsh, manager of commercial programs at rocket-maker United Launch Alliance.

NEW DATE SET. The launch has officially been rescheduled for Saturday during a window of 6:14 to 7:14 p.m. EDT.

Detanking of the rocket fuel from the Delta 4 is now underway.

Launch weather officer Joel Tumbiolo from the 45th Weather Squadron says he expects the same pattern of afternoon thunderstorms developing tomorrow and the next few days.

SCRUB! Weather has postponed the GOES O weather satellite launch. Thunderstorms, the associated clouds and lightning concerns all conspired to prevent the Delta 4 rocket from its scheduled liftoff at Cape Canaveral this evening.

The launch team will begin draining the cryogenic propellants from the two-stage vehicle and prepare for another countdown. Officials have not yet said if the next try will come on Saturday or not. The launch window would remain the same tomorrow: 6:14 to 7:14 p.m. EDT.

The weather outlook for Saturday calls for another round of afternoon thunderstorms and a 60 percent chance of unacceptable conditions at launch time.

Weather officer Joel Tumbiolo says conditions remain unacceptable and he doesn't see conditions coming back within limits for a launch today.

Twenty minutes remain in today's launch window.

Launch weather officer Joel Tumbiolo says he sees no indication that the clouds would dissipate anytime soon. There's still lightning in the area as the storms pass over the launch site.

The retargeted 6:44 p.m. EDT launch time has been pushed back further because of the weather, obviously. Clocks remain holding at T-minus 5 minutes. The window closes at 7:14 p.m. EDT.

Weather officer Joel Tumbiolo says conditions are "no go" and that two storm cells are expected to pass near the pad area in the next 10-15 minutes.

The launch team was just polled to confirm all systems are ready to proceed with the countdown, if the weather clears. There were no technical issues reported, but the local weather conditions remain "no go" at this time.

Menacing dark clouds hover over the spaceport. The countdown remains in a holding pattern as mission managers wait to see if there could be some break in the weather. Today's launch opportunity closes at 7:14 p.m. EDT.

The Phase 2 lightning advisory has been re-issued for the launch site as the next thunderstorm marches its way across the Cape.

Countdown clocks continue hold under dark and stormy skies.

The latest update from the launch weather officer doesn't give much optimism of conditions improving for liftoff during the window.

NEW LAUNCH TIME. Mission managers are planning to delay the liftoff 30 minutes and target a new launch time of 6:44 p.m. due to the unacceptable weather conditions at Cape Canaveral, NASA says.

The launch team has until 7:14 p.m. EDT to get the rocket airborne today or else wait until Saturday to try again.

T-minus 5 minutes and holding. The countdown has entered a planned 15-minute hold. But it is expected this hold will extended while mission managers wait on the weather.

This pause is designed to give the launch team the opportunity to catch up on any work running behind schedule and verify all is in readiness for the final moments of the count. A series of management polls will be conducted during the hold to give approval to proceed with the launch.

The weather situation remains unfavorable due to thunderstorms and lightning in the area.

All four liquid hydrogen and liquid oxygen tanks aboard the rocket are in topping mode. Delta is fueled up and ready to fly, if the weather allows. This evening's launch opportunity extends from 6:14 to 7:14 p.m. EDT.

The steering tests are reported complete and the results satisfactory.

The engine slew checks are being performed. The test sequence starts with the upper stage RL10 engine, followed by the first stage RS-68 engine gimbaling and then some commanding checks for the strap-on solid rocket motors.

Inspections of the rocket's thermal insulation have been completed with no concerns reported.

The weather reconnaissance aircraft is airborne to evaluate conditions and feed the real-time observations back to the launch weather team at the Air Force's 45th Weather Squadron. The official launch forecast still predicts a 70 percent chance that weather will prohibit a liftoff today.

Now entering the final 60 minutes of the countdown.

The field mills, which register the electrical potential in the air, have gone out of limits for launch. That adds to the list of launch weather rule violations. The criteria for anvil clouds, cumulus clouds and lightning are red as well.

Also about to begin will be the engine steering tests.

The RS-68 first stage main engine spin start pressurization operation is about to start.

The anvil cloud and lightning weather rules have now gone into "no go" condition for launch as storms near the coast from the west. The cumulus cloud rule remains "red" as well.

Health checks of the command receiver decoder devices on the rocket are underway. These units would hear the command from Range Safety and trigger the Delta 4's destruct system if a problem occurred during launch.

Now 90 minutes from liftoff time. The Delta 4 rocket's four propellant tanks are filled up and will be replenished to replace the cryogenics that naturally boil away through the rest of the countdown.

There are no technical issues being worked by the launch team. However, cloud conditions are "no go" for launch right now.

The weather status is "no go" again due to cumulus clouds over the launch site.

The RF link checks between the rocket and ground are being performed.

Engineers are conducting the standard evaluation of the Delta 4 rocket's thermal insulation following the loading of supercold propellants into the vehicle.

The upper level wind conditions are favorable for launch, NASA says.

Fast-fill loading of the upper stage liquid hydrogen tank has been completed.

Launch of the Delta 4 rocket is two hours away. The countdown remains on track and current weather conditions are within limits for today's liftoff of the GOES O meterological observatory.

"On a personal note, I've worked on this GOES program for 11-and-a-half years now, almost half of my career, and it's truly an honor to be involved in a mission like this. There's something special about working on a mission that affects so many people's lives on a day-to-day basis. In the case of severe weather, (we're) really talking about the ability to save lives. For an old engineer like me, there's really nothing better than that," said Charlie Maloney, GOES O program manager at satellite-builder Boeing Space and Intelligence Systems.

"The GOES O will greatly improve weather monitoring with images that are two to three times more precisely located than previous environmental systems. The bottom line is it provides more accurate and precise weather forecasting and the ability to track severe environmental events such as hurricanes and cyclones. And what that really comes down to it really enables us to save lives, to be able to protect life and property."

"Our team is ready to go and execute this mission. I think there's a sense from our people just how important this mission to this nation," added Andre Dress, GOES O deputy project manager from NASA's Goddard Space Flight Center.