FRIDAY, MARCH 4, 2011
7:00 a.m. local (10:00 a.m. EST)
For the second flight in a row, a solid-fueled Taurus rocket failed to orbit a NASA climate research satellite Friday because the launcher's nose shroud clung to the booster after it was supposed to jettison.

The extra burden of the payload fairing kept the Taurus rocket from attaining the required velocity and altitude to achieve orbit, causing the Taurus upper stage and NASA's $424 million Glory climate satellite to fall back to Earth.

Read our full story.

6:00 a.m. local (9:00 a.m. EST)
In the wake of the unsuccessful Taurus in February 2009 that lost NASA's Orbiting Carbon Observatory due to a nose cone separation failure, Orbital Sciences redesigned the system used by the rocket in preparation for today's flight with Glory.

Rich Straka, deputy general manager for operations at Orbital's Launch Systems Group, explains the changes:

"The Taurus uses a clamshell fairing and the fairing is held onto the vehicle, or constrained to the vehicle, with what we call frangible joints. Those joints are meant to explosively fracture when commanded to do so. When the joints explosively fracture, the fairing is then in two halves and there are piston pushers that push the fairing off.

"In the OCO vehicle and previous Taurus vehicles, we used what was called a hot-gas system to do that pushing job. There was a pyrotechnically initiated combustion process that generated hot gas, and the pressure of that hot gas pushing the pistons pushed the fairing halves apart.

"In the investigation, we identified the most probable cause of the OCO failure as a failure to initiate that hot-gas combustion process.

"So what we did in response to that is we swapped out or changed out, redesigned the deployment system to use a cold-gas system, which is a pressurized bottle of nitrogen that then when commanded functions by pressurizing those same pistons and pushing the fairing halves apart. It uses a completely different initiation system and a completely different pressurization methodology than the OCO system.

"We really felt like we had the problem nailed, and that particular (new cold-gas) system has flown three times last year, very similar system, almost identical system, flew in our Minotaur 4 product line successfully.

"So right now we're crunching the data but there's really not enough data that's been processed so far to really tell any more than the fairing didn't deploy."

5:50 a.m. local (8:50 a.m. EST)
"Let me just say that there's a great deal of emotional investment on the part of all the players on any spaceflight, but that's probably doubly so on a return-to-flight effort like this one," said Ron Grabe, general manager of Orbital's Launch Systems Group.

"I think it's not an understatement to say that tonight we're all pretty devastated. But we will recover. The team will bounce back because they're all professionals. And Orbital Sciences will bounce back with the Taurus vehicle."

5:45 a.m. local (8:45 a.m. EST)
Ron Grabe, general manager of Orbital's Launch Systems Group, said

"This is a pretty tough night for all of us. Little over two years ago, we had a similar tough night when we conducted a Taurus launch for the OCO mission. That mission suffered a failure - a failure of the fairing to separate. We conducted an extensive investigation of that anomaly and we traced the most probable cause to a failure of the fairing separation initiation system. We've spent the last two years doing the analysis on what went wrong that last time, redesigning the system and testing the components of the system. We went so far as to completely change out the initiation system to a system that we use on one of our other vehicles, the Minotaur 4 vehicle. And in the intervening two years, that system has flown successfully three times. So we really went into this flight feeling confident we had nailed the fairing issue. And then we came up with the result Omar described this evening."

5:35 a.m. local (8:35 a.m. EST)
Rich Straka, deputy general manager for operations at Orbital's Launch Systems Group, said it was too soon to know how the data from today's nose cone separation failure compares to the OCO fairing failure on the last Taurus:

"We really don't have any of the data processed yet. It's going to be several hours before we get a good look at the data. So it's too early to tell if it's the same thing we faced last time in terms of the symptoms and the data pattern. We just don't know right now. What I can say is we did put additional telemetry points and we do have additional instrumentation on this flight, so we do have a leg up on determining a root cause this time. But it's too early to tell if it is, in fact, the same cause."

Asked about the fairing jettison system redesign that's flown three times successfully on Minotaur 4 rockets last year and why it might have failed today on Taurus:

"The fairing system itself is very similar, but they are different fairings between the two vehicles. They are different sizes, for one thing. The Minotaur fairing is quite a bit larger, but it does use the same basic mechanisms, the same frangible joint system for separation, or the fracturing process, and the jettison system, the piston system, is almost identical. But there are differences in terms of the fairing size and the geometry of the fairing," Straka said.

5:20 a.m. local (8:20 a.m. EST)
NASA launch director Omar Baez at the post-failure press briefing:

"We lifted off at 2:09:43 this morning right on target. Stage 0 burned nominally for a minute, 25 seconds. Stage 1 then ignited and millisecond later we separated from the Stage 0 and continued flight. We did that till 2 minutes and 45 seconds where we had indication of burnout of the Stage 1 and we had ignition of Stage 2. About six seconds later after Stage 2 ignition, we were expecting to see the fairing on the T9 separate. We didn't see the indication of fairing separation. There were other indications such as performance loss we saw a little bit later on in flight.

"But we failed to make orbit, and all indications are that the satellite and the rocket (are) in the southern Pacific somewhere," Baez said, his voice trembling.

Asked by a reporter where the impact point was:

"We should be able to, it's just too preliminary to get the trajectory of where it ended up. But seeing that it's similar weight to what OCO was and same launch vehicle performance, physics says it's likely in the same spot or close to it."

3:40 a.m. local (6:40 a.m. EST)
The press conference from Vandenberg has been scheduled for 5 a.m. local (8 a.m. EST).
3:30 a.m. local (6:30 a.m. EST)
Back at the pre-launch news conference a couple of weeks ago, Baez was asked by a reporter about his comfort level going into this Taurus return-to-flight launch after the OCO failure two years ago:

"We've done everything we can. We've looked at that vehicle from a systems level down to the piece parts level. We've checked everything. We're as comfortable as we're gonna get. We really need to get this launch to be successful, and I think the whole team has done some soul searching and looked deep at everything we've done. I don't think we can uncover anything else. With that, that gives me a lot of comfort."

3:10 a.m. local (6:10 a.m. EST)
The protective nose cone of an Orbital Sciences Corp. Taurus XL rocket carrying NASA's Glory environmental research satellite apparently failed to separate after launch Friday, preventing the spacecraft from achieving orbit in a $424 million failure. It was the second nose cone failure in a row for a Taurus XL rocket following the 2009 loss of another environmental satellite.

Read our full story.

2:37 a.m. local (5:37 a.m. EST)
The declaration from NASA launch director Omar Baez when the failure was made official at 2:15 a.m.:

"Attention all stations, this is the NLM (NASA Launch Manager) on the Countdown and NLM Net. We have had a contingency on the Glory mission. Please enact the mission mishap preparedness and contingency plan. Begin with notification, data impoundment and mishap response tasks. Do not leave your stations until released by the NLM or the ALM. Do not attempt to call out and release information to anyone or speculate on the cause of the contingency."

2:34 a.m. local (5:34 a.m. EST)
Here's the call at the moment when the problem was first announced by Richard Haenke, the Taurus vehicle engineer:

"We are at T+plus 300 seconds. The vehicle speed error is indicating under-performance, which is expected due to a fairing not separating," the Orbital telemetry commentator said. "We have a report the system did pressurize. However, we still have no indication of the fairing separating."

2:30 a.m. local (5:30 a.m. EST)
NASA launch commentator George Diller:

"The flight was going well until the time of fairing separation, then we had data coming into the Mission Directors Center from our Vandenberg tracking station and Point Mugu that we did not have a successful fairing separation from the Taurus, and there was insufficient velocity with the fairing still on for the vehicle to achieve orbit."

2:23 a.m. local (5:23 a.m. EST)
Taurus debuted in 1994 and has six successful flights to its credit, putting 10 satellites into orbit. It has failed three times, including now two in a row.
2:21 a.m. local (5:21 a.m. EST)
NASA will hold a post-failure news conference within the next couple of hours.
2:20 a.m. local (5:20 a.m. EST)
Rocket-maker Orbital Sciences and NASA had spent the past two years troubleshooting and redesigning the nose cone separation system after the Orbiting Carbon Observatory was lost in February 2009. The new system has flown successfully already aboard Minotaur vehicles. But this return-to-flight for Taurus has failed because the fairing remains attached and the vehicle doesn't have enough speed to reach orbit with all that extra weight.
2:17 a.m. local (5:17 a.m. EST)
The rocket continues to fly downrange. But it won't be a successful outcome this morning because of the nose cone remains affixed to the rocket.
2:16 a.m. local (5:16 a.m. EST)
This is the second straight failure for the Taurus XL rocket because of a problem jettisoning the payload shroud from around the payload during ascent.
2:15 a.m. local (5:15 a.m. EST)
LAUNCH FAILURE DECLARED by NASA launch director Omar Baez.
2:14 a.m. local (5:14 a.m. EST)
T+plus 5 minutes, 25 seconds. The vehicle's speed is under-performing. Engineering believes the nose cone did not separate.
2:14 a.m. local (5:14 a.m. EST)
T+plus 4 minutes, 30 seconds. The third stage has finished firing. The Taurus rocket now enters a brief ballistic coast to reach the high point of its current trajectory before the fourth stage ignites to circularize the orbit.
2:12 a.m. local (5:12 a.m. EST)
T+plus 3 minutes. Burnout and separation of the rocket's second stage just occurred. And now the Orion 50XL third stage has been lit.
2:12 a.m. local (5:12 a.m. EST)
T+plus 2 minutes, 40 seconds. Taurus is traveling at 9,500 mph at an altitude of 100 miles.
2:11 a.m. local (5:11 a.m. EST)
T+plus 2 minutes. The rocket is stable and all systems nominal as the Orion 50SXLG second stage continues to burn.
2:11 a.m. local (5:11 a.m. EST)
T+plus 1 minute, 30 seconds. The initial staging event of the launch has occurred. The rocket's second stage ignited and the spent first stage was jettisoned to fall into the Pacific Ocean.
2:10 a.m. local (5:10 a.m. EST)
T+plus 55 seconds. Vehicle speed is 2,000 mph already, some 10 miles in altitude.
2:10 a.m. local (5:10 a.m. EST)
T+plus 45 seconds. Passing through the region of maximum aerodynamic pressure in the dense lower altitudes of the atmosphere.
2:10 a.m. local (5:10 a.m. EST)
T+plus 30 seconds. Taurus has passed Mach 1, now traveling faster than the speed of sound as it heads south toward a polar orbit on the power of the Castor 120 first stage motor.
2:09:43 a.m. local (5:09:43 a.m. EST)
LIFTOFF! Liftoff of the Orbital Sciences Taurus XL rocket and the Glory observatory to probe the natural and man-made forces driving Earth's climate.
2:09:13 a.m. local (5:09:13 a.m. EST)
T-minus 30 seconds. All remains "go" for launch.
2:08:43 a.m. local (5:08:43 a.m. EST)
T-minus 1 minute and counting to launch of NASA's Glory satellite.
2:08:13 a.m. local (5:08:13 a.m. EST)
T-minus 90 seconds. Auto sequence start.
2:07:43 a.m. local (5:07:43 a.m. EST)
T-minus 2 minutes and counting.
2:07:23 a.m. local (5:07:23 a.m. EST)
T-minus 2 minutes, 20 seconds. SIGI flight computer is in "navigation" mode.
2:06:43 a.m. local (5:06:43 a.m. EST)
T-minus 3 minutes and counting. Taurus has been armed and ignition is enabled.
2:04:53 a.m. local (5:04:53 a.m. EST)
T-minus 4 minutes, 50 seconds. Orbital Sciences' launch conductor Adam Lewis has performed his "final clear to launch" readiness poll. Everyone voiced a "go" to launch at 2:09 a.m. local time.
2:04:13 a.m. local (5:04:13 a.m. EST)
T-minus 5 minutes, 30 seconds. The rocket's rate gyro guidance system has been started.
2:03:43 a.m. local (5:03:43 a.m. EST)
T-minus 6 minutes and counting. The S-band data transmitters have been turned on. And engineers verify telemetry streaming from the rocket's systems is being received.
2:02:43 a.m. local (5:02:43 a.m. EST)
T-minus 7 minutes and counting. Glory has been confirmed ready for launch.
2:01:43 a.m. local (5:01:43 a.m. EST)
T-minus 8 minutes and counting. The Taurus rocket's avionics are going to internal power for launch.
2:00 a.m. local (5:00 a.m. EST)
T-minus 9 minutes, 30 seconds. Glory is running normally on internal power.
1:58:43 a.m. local (4:58:43 a.m. EST)
T-minus 11 minutes and counting. The Glory spacecraft is switching to internal battery power for its ride into orbit.
1:57:43 a.m. local (4:57:43 a.m. EST)
T-minus 12 minutes and counting. Clocks have resumed ticking after the planned 5-minute hold. Liftoff remains scheduled for 2:09:43 a.m. local (5:09:43 a.m. EST).
1:56 a.m. local (4:56 a.m. EST)
The launch team was just polled to give approval for switching Taurus' avionics to internal power.
1:52 a.m. local (4:52 a.m. EST)
T-minus 12 minutes and holding. The countdown has entered the second of two planned built-in holds. This pause will last 5 minutes and syncs the clocks with the preferred liftoff time of 2:09:43 a.m. local (5:09:43 a.m. EST).

Everything is progressing for an on-time launch of the Taurus XL rocket from the Space Launch Complex 576E pad at Vandenberg Air Force Base in California.

1:50 a.m. local (4:50 a.m. EST)
NASA launch director Omar Baez has conducted a final poll of the agency team. All elements remain ready for flight this morning.
1:47 a.m. local (4:47 a.m. EST)
Checks of the safety system have been conducted successfully.
1:45 a.m. local (4:45 a.m. EST)
The safety system is switching to internal power for pre-launch checks.
1:39 a.m. local (4:39 a.m. EST)
The launch team has been given a "go" to power on the rocket's flight termination system. This is the safety feature that would be used in the unlikely event the rocket experiences a malfunction during launch.
1:34 a.m. local (4:34 a.m. EST)
Now 35 minutes from liftoff. Upper level winds have been confirmed favorable for the Taurus rocket's ascent.
1:32 a.m. local (4:32 a.m. EST)
The launch weather officer provided another briefing to management. The marine layer has pushed back offshore from the pad and there's a 100 percent chance of acceptable conditions for today's launch.

The latest forecast for liftoff time predicts a few high cirrus clouds at 25,000 feet, good visibility, northeasterly winds of 12 to 18 knots and a temperature of 50 degrees F.

1:27 a.m. local (4:27 a.m. EST)
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1:25 a.m. local (4:25 a.m. EST)
The SIGI flight computer is reported "nav ready."
1:20 a.m. local (4:20 a.m. EST)
Alignment of the Taurus rocket's guidance computer is being confirmed.
1:19 a.m. local (4:19 a.m. EST)
T-minus 45 minutes and counting. Clocks have resumed ticking after the planned 15-minute hold. Another hold will occur later in the countdown. Liftoff remains scheduled for 2:09:43 a.m. local (5:09:43 a.m. EST).
1:17 a.m. local (4:17 a.m. EST)
Orbital Sciences' launch conductor Adam Lewis has performed his readiness poll for picking up the countdown following the built-in hold.

"Launch team is ready to proceed with the start of Hot Count," Lewis said.

1:14 a.m. local (4:14 a.m. EST)
NASA launch director Omar Baez has polled of the agency team with no constraints reported. "NASA team is ready to proceed into Hot Count."
1:09 a.m. local (4:09 a.m. EST)
Now 60 minutes away from blastoff of the Taurus rocket with Glory.
1:04 a.m. local (4:04 a.m. EST)
T-minus 45 minutes and holding. The countdown has entered the first of two planned built-in holds. This pause will last 15 minutes.

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.

12:55 a.m. local (3:55 a.m. EST)
The Taurus safety system has switched from ground-fed power to internal power for a few moments so the launch team can verify no problems.
12:49 a.m. local (3:49 a.m. EST)
The rocket's power systems have been tested and telemetry being received shows good voltage and current readings.
12:44 a.m. local (3:44 a.m. EST)
And confirmation now received that the S-band and C-band tracking tests are finished with good results.
12:40 a.m. local (3:40 a.m. EST)
Interrogation checks of the rocket's tracking beacon and telemetry data links are being completed. The S-band data and C-band tracking tests are performed with the Range to verify good connections for launch.
12:35 a.m. local (3:35 a.m. EST)
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12:33 a.m. local (3:33 a.m. EST)
NASA says all systems are "go" in this second attempt to launch Taurus with Glory. Activities are running on schedule this morning.
12:19 a.m. local (3:19 a.m. EST)
T-minus 90 minutes and counting. Clocks are ticking toward liftoff of the Taurus XL rocket. This countdown includes a pair of planned hold points totaling 20 minutes in duration, leading toward the target liftoff time of 2:09:43 a.m. local (5:09:43 a.m. EST).
12:15 a.m. local (3:15 a.m. EST)
Good morning and welcome to our launch coverage of the Taurus XL rocket carrying the Glory observatory from Vandenberg Air Force Base in California.

Final launch preparations are underway at the SLC-576E pad for the 2:09 a.m. PST liftoff.

The simplistic launch site does not have a mobile service gantry. So there's no tower rollback to deal with like other rocket launches. And this is a solid-propellant vehicle. So no fueling operations are conducted during the countdown.

THURSDAY, MARCH 3, 2011
With a ground software fault found and fixed, the Taurus rocket has been cleared to resume preparations for launch early Friday from Vandenberg Air Force Base, California.

The original launch attempt to deploy NASA's Glory spacecraft was scrubbed February 23 when the ground control system erroneously indicated a "hold-fire" safe command had been issued.

Extensive troubleshooting to figure out the problem revealed the fault had gotten into the system during a previous prelaunch test. Officials say the configuration has been corrected and procedures revised to ensure the glitch can't reoccur.

The launch readiness review was held Wednesday and confirmed the mission was "go" to proceed into the countdown.

Liftoff is scheduled for 2:09:43 a.m. local (5:09:43 a.m. EST).

Weather forecasters are predicting no chance of conditions preventing a Friday launch. But the marine layer could come ashore and bring low clouds and fog to hamper the view on-base at Vandenberg.

The specifics for launch time include stratus from the surface to 500 feet, some high cirrus at 28,000 feet, only three miles of visibility with fog, northwesterly winds of 12 to 18 knots and a temperature around 50 degrees F.

Our live launch coverage will begin at 12:30 a.m. local (3:30 a.m. EST).

THURSDAY, FEBRUARY 24, 2011
Officials have put off the Taurus launch until early March so the ground system problem can be sorted out, fixed and retested.
WEDNESDAY, FEBRUARY 23, 2011
Launch managers say the next attempt to fly the Taurus XL booster carrying NASA's Glory climate satellite won't come until at least Friday morning at 2:09 a.m. local (5:09 a.m. EST) from Vandenberg Air Force Base, California.

After this morning's scrub, officials initially preserved the option of trying again as early as Thursday morning.

But NASA says further time is necessary to understand and resolve the technical problem before heading into the next countdown. Moving the target day to Friday also ensures the team can get some rest before the overnight launch attempt.

The weather outlook for Friday's launch time gives only a 40 percent chance of acceptable conditions. Thick clouds will be the concern as a low pressure system impacts the Vandenberg area.

2:40 a.m. local (5:40 a.m. EST)
Launch of the Taurus XL rocket with NASA's Glory spacecraft was scrubbed this morning when a mysterious problem late in the countdown prevented the ground team from proceeding with steps to ready the booster for flight.

"The team is still trying to work out what the issue was," said Chuck Dovale, deputy director of NASA's launch services program.

"There is a set of ground support equipment called the Vehicle Interface Control Console that basically controls and provides status of the launch vehicle systems, what configuration they are in, whether it's safe or not. It appears a 'hold-fire' was noticed, which basically means a 'safe' condition was sent. The curious part of that is the vehicle was already 'safe,' so it was an external signal that indicated that the vehicle should be safed. So we didn't quite understand why we were getting that indication.

"This VICC -- Vehicle Interface Control Console -- there is a backup unit to it. The team quickly adjusted to the backup but were getting the same indications as the prime. So clearly it wasn't an indication of just a piece of (ground support equipment) that went bad.

"I think the biggest problem is the issue occurred about L-minus 12 minutes or so, and with basically no room for flexibility of a long window we just ran out of time for troubleshooting (for a launch today).

"Troubleshooting is continuing. We had to make sure we understood the vehicle configuration and that we could get it safed. We're in the process of doing that.

"We don't understand the problem at the moment. I can just tell you we're going to troubleshoot it the next few hours and we certainly won't continue until we understand it. We are posturing for a 24-hour turnaround in the event we can find a root cause and hopefully try again tomorrow."

Dovale added further that this VICC is used to commanding the rocket. "Yea, it provides control. So when the vehicle goes from a 'safe' to an 'arm' condition, this is the equipment that is providing that. It's in the Launch Equipment Van."

"Like I say, we were in a 'safe' mode and it externally received a signal to go into the 'safe' mode. We don't quite understand why that occurred."

As the team initially began working the problem, it held up approval to place the rocket on internal power. Then time quickly expired to achieve a launch in the day's strict 47-second liftoff window. A scrub became the obvious outcome.

2:11 a.m. local (5:11 a.m. EST)
The weather forecast for tomorrow calls for a 100 percent chance of acceptable conditions for the Taurus liftoff. But meteorologists are predicting lots of low clouds and fog that could hamper the view for spectators.

The specifics include stratus clouds at the surface to 500 feet, some high cirrus clouds at 20,000 feet, only 2 miles of visibility with fog, northwesterly winds and a temperature in the mid-40s F.

2:09 a.m. local (5:09 a.m. EST)
The launch time tomorrow is unchanged from today.
2:08 a.m. local (5:08 a.m. EST)
Glory has gone back to external power for this one-day delay in the launch.
2:04 a.m. local (5:04 a.m. EST)
The launch team is implementing a 24-hour recycle of the countdown to try again tomorrow.
2:03 a.m. local (5:03 a.m. EST)
The countdown officially stopped at T-minus 7 minutes, 41 seconds.
2:02 a.m. local (5:02 a.m. EST)
This effectively scrubs today's liftoff attempt because the available launch window extends only 47 seconds to reach Glory's desired orbit.
2:02 a.m. local (5:02 a.m. EST)
HOLD. The countdown has been stopped.
2:00 a.m. local (5:00 a.m. EST)
A problem is preventing the launch team from putting the rocket on internal power. It appears to be an issue with ground commanding.
2:00 a.m. local (5:00 a.m. EST)
T-minus 9 minutes, 30 seconds. Glory is running normally on internal power.
1:58:43 a.m. local (4:58:43 a.m. EST)
T-minus 11 minutes and counting. The Glory spacecraft is switching to internal battery power for its ride into orbit.
1:57:43 a.m. local (4:57:43 a.m. EST)
T-minus 12 minutes and counting. Clocks have resumed ticking after the planned 5-minute hold. Liftoff remains scheduled for 2:09:43 a.m. local (5:09:43 a.m. EST).
1:52 a.m. local (4:52 a.m. EST)
NASA says the boat will be cleared in time for launch this morning.
1:52 a.m. local (4:52 a.m. EST)
T-minus 12 minutes and holding. The countdown has entered the second of two planned built-in holds. This pause will last 5 minutes and syncs the clocks with the preferred liftoff time of 2:09:43 a.m. local (5:09:43 a.m. EST).

Everything is progressing for an on-time launch of the Taurus XL rocket from the Space Launch Complex 576E pad at Vandenberg Air Force Base in California.

1:50 a.m. local (4:50 a.m. EST)
NASA launch director Omar Baez has conducted a final poll of the agency team. All elements remain ready for launch except for the boat in the hazard area offshore. Efforts continue to clear that constraint.
1:47 a.m. local (4:47 a.m. EST)
Checks of the safety system have been conducted successfully.
1:45 a.m. local (4:45 a.m. EST)
The safety system is switching to internal power for pre-launch checks.
1:39 a.m. local (4:39 a.m. EST)
The launch team has been given a "go" to power on the rocket's flight termination system. This is the safety feature that would be used in the unlikely event the rocket experiences a malfunction during launch.
1:34 a.m. local (4:34 a.m. EST)
Now 35 minutes from liftoff. Upper level winds have been confirmed favorable for the Taurus rocket's ascent.
1:32 a.m. local (4:32 a.m. EST)
The launch weather officer provided another briefing to management. There's now a 100 percent chance of acceptable conditions for today's launch.

The latest forecast for liftoff time predicts a few high cirrus clouds at 20,000 feet, good visibility, northeasterly winds of 12 to 18 knots and a temperature in the low 40s F.

1:27 a.m. local (4:27 a.m. EST)
NASA says there is a boat within the restricted waters downrange from the launch pad. Efforts are underway to get that vessel out of the way.
1:25 a.m. local (4:25 a.m. EST)
The SIGI flight computer is reported "nav ready."
1:20 a.m. local (4:20 a.m. EST)
Alignment of the Taurus rocket's guidance computer is being confirmed.
1:19 a.m. local (4:19 a.m. EST)
T-minus 45 minutes and counting. Clocks have resumed ticking after the planned 15-minute hold. Another hold will occur later in the countdown. Liftoff remains scheduled for 2:09:43 a.m. local (5:09:43 a.m. EST).
1:17 a.m. local (4:17 a.m. EST)
Orbital Sciences' launch conductor Adam Lewis has performed his readiness poll for picking up the countdown.

"Launch team is ready to proceed with the start of Hot Count," Lewis said.

A few minutes ago, NASA launch director Omar Baez had polled the agency team to confirm there are no constraints with restarting the countdown following the built-in hold.

1:09 a.m. local (4:09 a.m. EST)
Now 60 minutes away from blastoff of the Taurus rocket with Glory.
1:04 a.m. local (4:04 a.m. EST)
T-minus 45 minutes and holding. The countdown has entered the first of two planned built-in holds. This pause will last 15 minutes.

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.

12:59 a.m. local (3:59 a.m. EST)
The Taurus safety system just switched from ground-fed power to internal power for a few moments so the launch team could verify no problems.
12:49 a.m. local (3:49 a.m. EST)
The rocket's power systems have been tested and telemetry being received confirms good voltage and current readings.
12:37 a.m. local (3:37 a.m. EST)
Interrogation checks of the rocket's tracking beacon and telemetry data links are complete. The S-band data and C-band tracking tests were performed with the Range to verify good connections for launch.
12:35 a.m. local (3:35 a.m. EST)
NASA says no problems are being worked in the countdown and things remain on schedule this morning.
12:30 a.m. local (3:30 a.m. EST)
Space Launch Complex 576E has been cleared of all workers for the remainder of the countdown. Earlier tonight, the teams worked through the facility and range setup checklists and the final launch site configuration checklist before powering up of the Taurus rocket.
12:19 a.m. local (3:19 a.m. EST)
T-minus 90 minutes and counting. Clocks are ticking toward liftoff of the Taurus XL rocket. This countdown includes a pair of planned hold points totaling 20 minutes in duration, leading toward the target liftoff time of 2:09:43 a.m. local (5:09:43 a.m. EST).
10:00 p.m. local (1:00 a.m. EST)
Mission managers and the launch crew have reported for duty for the overnight flight of the Taurus XL rocket carrying the Glory observatory from Vandenberg Air Force Base in California.

Final launch preparations are underway at the SLC-576E pad as workers finish configuring the complex for the 2:09 a.m. PST liftoff.

The simplistic launch site does not have a mobile service gantry. So there's no tower rollback to deal with like other rocket launches.

And this is a solid-propellant vehicle. So no fueling operations are conducted during the countdown.

Our live play-by-play reports on the countdown will begin at 12:30 a.m. local (3:30 a.m. EST).

TUESDAY, FEBRUARY 22, 2011
The protective coverings have been removed from the Taurus XL rocket's first stage as ground crews ready for the tonight's countdown and tomorrow's predawn blastoff.

Forecasters are predicting acceptable weather for the 2:09 a.m. local time (5:09 a.m. EST; 1009 GMT) launch from Vandenberg Air Force Base, California.

The outlook calls for a few low clouds at 3,000 feet, some high cirrus clouds at 25,000 feet, good visibility, a temperature between 40-45 degrees F and northwesterly winds of 12 peaking to 18 knots.

Watch this page for live coverage during the launch.

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MONDAY, FEBRUARY 21, 2011
A Taurus XL rocket and its climate-probing satellite payload are awaiting blastoff early Wednesday from a minimalist launch pad at Vandenberg Air Force Base, California.

Liftoff is scheduled for the exact moment of 2:09:43 a.m. local (5:09:43 a.m. EST) to deliver NASA's Glory spacecraft into polar orbit to study how atmospheric particles called aerosols and the Sun's energy influence Earth's climate.

"Glory is buckled atop the Taurus right now and we're ready for its ride to get to space," said Bryan Fafaul, the Glory project manager. "We have worked very hard to get Glory configured for launch and I want to ensure you that Glory is ready to go to work."

Known for its simplistic launch site devoid of any large gantry or major infrastructure, the Taurus rocket is a four-stage, all solid-fuel booster designed to carry small satellites into space.

Operated by Orbital Sciences, the Taurus is a ground-based rocket derived from the company's air-launched Pegasus vehicle. In fact, the Taurus and Pegasus use three common stages. But what makes Taurus different is the addition of a bottom stage to power the initial climb away from Earth.

Stacking of the Taurus rocket began January 17 when the first stage was mounted atop the pad's pedestal, a 24-foot tall stand affectionally dubbed the milk stool.

The first stage is a Castor 120 motor manufactured by Alliant Techsystems, the maker of all four Taurus stages.

The upper three motors are the Orion 50SXLG second stage, the Orion 50XL third stage and the Orion 38 fourth stage. They were integrated in Orbital's Building 1555 hangar at Vandenberg, then hauled to the Taurus pad via a special trailer on January 25.

Once at the pad, the site of an abandoned missile silo and now known as Space Launch Complex 576E, the three combined upper stages were housed inside a large portable tent where the final assembly work between the rocket and satellite could be performed in a safe horizontal position.

Glory underwent testing in a processing facility after arriving at the base on January 11, then got enclosed within the two-piece shroud that serves as the rocket's 63-inch-diameter nose cone during launch. Technicians trucked the encapsulated satellite to the pad on February 5, rotating it horizontal at the tent's doorway to join the waiting rocket stages.

Three tiny cubesats built by universities were added to the rocket's upper stage on February 6. They will be ejected from a deployer box moments after Glory is cast free into orbit.

The tent was moved out of the way last Tuesday, giving large cranes brought into the pad full access to the combined stages and Glory.

Two cranes working in tandem hoisted the upper stack off the horizontal transporter about 10:45 a.m. and turned the slender space hardware into a vertical position. Within minutes, the rocket was maneuvered atop the first stage waiting on the pad.

Crews quickly went to work bolting the upper portion of the vehicle to the first stage. Later, technicians standing in the basket of a cherry-picker released the lifting fixtures that held the rocket during the move.

There is no mobile service structure or towering gantry at the Taurus pad. Simple scaffolding temporarily erected around the first stage and the cranes give workers the access they require during the rocket's brief stay on the pad.

Now standing fully assembled, the Taurus is 93 feet tall and 81 tons in weight.

Final testing and readiness reviews have taken place over the next few days leading into the countdown.

"We are clean, green and ready to go," NASA launch director Omar Baez said Monday afternoon.

Weather forecasters are predicting favorable conditions for the launch.

Watch this page for live updates during the count and the ascent into orbit!