BY JUSTIN RAY

Follow the countdown and launch of the Boeing Delta 2 rocket with the NOAA-N polar orbiting weather satellite. Reload this page for the very latest on the mission.

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MONDAY, MAY 16, 2005

Launch of the Delta 2 booster with the NOAA-N weather satellite is now targeted for Friday morning, a day later than originally envisioned, due to other unrelated rocket testing activity at Vandenberg Air Force Base that has the Western Range's services already reserved.

Nine of the 17 samples taken of the spacecraft, nose cone and rocket to check for hydrocarbon contamination have been tested and revealed no concerns. Results from the remaining 8 samples are expected on Tuesday.

Friday's 10-minute launch window opens at 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT).

SATURDAY, MAY 14, 2005
2115 GMT (5:15 p.m. EDT)

Technicians at the Delta 2 rocket launch pad will spend Sunday collecting 17 inspection samples to determine if the NOAA-N spacecraft was contaminated by hydrocarbons when a fuel vent hose accidently unhooked Friday.

Officials met this morning to decide how and where to obtain the samples. Most of the 17 samples will be taken from the satellite tucked inside the rocket's nose cone, while a few will come from the launch vehicle itself.

The procedures are being written today. The sampling should be completed during one work shift Sunday.

Results of the tests are expected to be reviewed by a senior management meeting on Monday afternoon.

"The feeling is that it's unlikely that there is a hydrocarbon problem, but the samples are necessary to rule it out," NASA spokesman George Diller said in a statement.

The trouble stems from a kerosene propellant vent hose that broke free while the launch team was draining 10,000 gallons of the fuel from the rocket's first stage after Friday morning's launch attempt was scrubbed. The countdown was cancelled by electrical problems at the launch pad.

Assuming the samples don't reveal any problems, a Launch Readiness Review is being scheduled for Tuesday to formally approve proceeding with the next liftoff attempt. The 30-hour countdown would commence Tuesday night, leading to launch around 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) on Thursday.

However, a Thursday launch opportunity is pending an available slot on the Air Force-controlled Western Range at Vandenberg.

0420 GMT (12:20 a.m. EDT)

Managers have ordered inspections of the NOAA-N weather satellite before it is launched into polar orbit by a Boeing Delta 2 booster after a hose inside the rocket broke loose Friday.

The $341 million mission's Saturday launch shot has been postponed as a result, delaying the liftoff to late next week. It is the mission's fourth consecutive launch date to be cancelled after high winds on Tuesday and Wednesday nights and electrical problems at the pad Friday morning.

The vent hose somehow became disconnected when technicians were draining kerosene propellant from the rocket's first stage following Friday morning's launch scrub, NASA announced. The incident potentially allowed hydrocarbons to enter the payload fairing nose cone that encapsulates NOAA-N atop the 12-story rocket.

Samples will be taken to verify that the satellite hasn't been harmed. It is a precautionary measure to ensure NOAA-N is healthy before it rockets into space.

"They can't prove that we don't have a problem," NASA spokesman George Diller said. "So we've got to do witness samples to make sure."

Launch has been tentatively rescheduled for no earlier than Thursday at 1022 GMT. The lengthy wait gives technicians time to do their satellite checks, plus fulfill orbital requirements to ensure proper spacing between NOAA-N and a sister-spacecraft already circling Earth. This spacing is dictated by a ground tracking station, which results in liftoff being restricted to four-day windows and then blackout periods lasting four or five days.

0325 GMT (11:25 p.m. EDT Fri.)

Launch has been delayed to next Thursday at the earliest, NASA says.

After Friday morning's countdown was scrubbed, a purge line became disconnected at the launch pad. Officials are concerned about possible contamination in the rocket's nose cone. While officials assess this issue, they must wait until mid-week before the next launch opportunity because of orbital mechanics constraints placed on delivery of NOAA-N into the desired perch above Earth.

0258 GMT (10:58 p.m. EDT Fri.)

SCRUB! Saturday morning's launch attempt has been called off. Launch is not expected to occur before Wednesday or Thursday. We'll post more details as they become available.

FRIDAY, MAY 13, 2005
2225 GMT (6:25 p.m. EDT)

Technicians have repaired the electrical problems with the launch pad water suppression system pumps today, allowing teams to prepare for another countdown tonight.

"We're pressing on," NASA spokesman George Diller says.

Although one of the pad's four pumps remains failed, the three remaining units were brought back online and successfully re-tested following this morning's scrub. The three pumps must operate correctly through tonight's countdown because launch rules require three of four to be functioning. A spare is not available to replace the faulty pump.

Weather conditions appear favorable for this fourth launch attempt. Although heavy fog is expected to develop this evening, there are no worries about violating the launch criteria.

The first stage will be re-fueled with kerosene propellant around 0000 GMT (8 p.m. EDT; 5 p.m. PDT), followed within two hours by retraction of the mobile service tower.

Saturday morning's 10-minute launch opportunity extends from 1022 to 1032 GMT (6:22-6:32 a.m. EDT; 3:22-3:32 a.m. PDT).

If the Delta 2 rocket does not launch overnight, the mission will be delayed four days to await the next acceptable orbital mechanics window for placement of the NOAA-N weather satellite into space.

0950 GMT (5:50 a.m. EDT)

Today's scheduled California liftoff of the Boeing Delta 2 rocket to deploy the latest polar-orbiting weather satellite was scrubbed by electrical gremlins in the system that floods the launch pad with critical cooling and sound-dampening water during the fiery blastoff. Read our full story.

0935 GMT (5:35 a.m. EDT)

We have posted a movie of today's launch scrub announcement. The video is available to Spaceflight Now Plus subscribers.

0930 GMT (5:30 a.m. EDT)

The launch team is draining the RP-1 kerosene fuel from the first stage as part of normal scrub procedures. This propellant was pumped into the rocket last night, and will be re-loaded into the vehicle Friday evening during the next countdown.

0901 GMT (5:01 a.m. EDT)

Officials are planning another launch attempt tomorrow. Liftoff time on Saturday morning is targeted for 1022 GMT.

0900 GMT (5:00 a.m. EDT)

SCRUB! Today's countdown has been scrubbed. There is not enough time to correct an electrical problem at the launch pad, finish fueling the vehicle and ready the Delta rocket for liftoff by the end of today's short 10-minute window that closes at 1032 GMT.

0857 GMT (4:57 a.m. EDT)

NASA Launch Manager Omar Baez has delayed his polling to 0910 GMT.

Once the pump house electrical problem is fixed, the three water deluge pumps within the house will be reactivated one at a time and their health evaluated, NASA says. The fourth pump failed a little while ago, but only three are required for launch.

0852 GMT (4:52 a.m. EDT)

Today's launch window opens in 90 minutes. The precise window extends from 1022:01 to 1032:01 GMT to ensure the Delta rocket launches the NOAA-N spacecraft into the desired orbit around Earth's poles.

0850 GMT (4:50 a.m. EDT)

Liquid oxygen fueling of the Delta rocket's first stage remains on hold while the electrical troubleshooting continues.

A status report from the engineering team on the efforts to resolve the power problem at the launch pad water deluge pump house is expected in about five minutes. Management is expected to decide around the top of the hour whether there is enough time to resolve this issue and still make a launch attempt within this morning's 10-minute liftoff window. If time runs out, the launch will have to be delayed 24 hours.

0843 GMT (4:43 a.m. EDT)

Work to activate the Delta rocket's guidance system has been completed. The RIFCA flight computer is up and operating.

0838 GMT (4:38 a.m. EDT)

NASA Launch Manager Omar Baez indicates that liftoff probably will slip to the end of today's available window, which closes at 1032 GMT, assuming the pad issue can be resolved this morning.

0836 GMT (4:36 a.m. EDT)

NASA spokesman George Diller says managers anticipate making a decision around 0900 GMT on whether to continue with the countdown. Crews are at the pad to do hands-on troubleshooting with the electrical glitch.

0833 GMT (4:33 a.m. EDT)

Liquid oxygen loading, which was supposed to begin in a few minutes, has been delayed while the launch pad water pump troubleshooting progresses. The fate of this morning's launch attempt is somewhat uncertain at the moment.

0825 GMT (4:25 a.m. EDT)

The engineering discussions continue. Management should be making a call shortly.

0820 GMT (4:20 a.m. EDT)

The launch weather officer just completed a scheduled briefing to management in advance of liquid oxygen loading. All conditions are acceptable and forecast to remain that way through today's 10-minute launch window. The outlook for tomorrow, should the launch be delayed for any reason, is favorable.

0816 GMT (4:16 a.m. EDT)

Engineers are estimating it will take about an hour to work on the power problem for the launch pad water deluge pump house, NASA says. Managers are trying to determine if there is enough time left in the countdown to do this unplanned work, fill the first stage with liquid oxygen and complete the final hour of the countdown activities.

0815 GMT (4:15 a.m. EDT)

The next event in the countdown is loading liquid oxygen into the first stage. That is supposed to start in about 20 minutes. However, the operation would likely be delayed based on these pad problems.

0811 GMT (4:11 a.m. EDT)

A NASA spokesman says in addition to the water pump issue, there is a problem with the power going into the pump house at the pad. Officials are discussing the possibility of sending an electrical crew to the pad, and whether there is sufficient time to address this situation and still reach the 1022 GMT launch time this morning. The available launch window today is just 10 minutes in length.

0801 GMT (4:01 a.m. EDT)

Launch of the NOAA-N spacecraft to track global weather patterns aboard the Boeing Delta 2 rocket from Vandenberg Air Force Base in California remains on schedule for 1022 GMT this morning.

However, the launch team is addressing a problem with one of the water deluge pumps at the pad. A crew is troubleshooting the issue. There are four pumps at Space Launch Complex-2 West, and three are required for launch.

0746 GMT (3:46 a.m. EDT)

The first stage helium and nitrogen system pressurization has been completed.

0742 GMT (3:42 a.m. EDT)

Normally at this point in a Delta 2 rocket countdown the first stage fuel loading would begin. However, managers opted to fill the stage with its supply of 10,000 gallons of kerosene propellant several hours ago before mobile service tower rollback. The early fueling operation was designed to add weight to the rocket, giving the vehicle added stability in the wind once the protective gantry was retracted.

0728 GMT (3:28 a.m. EDT)

The "go" has been given to the launch for pressurizing the helium and nitrogen storage tanks inside the rocket's first and second stages, along with the second stage fuel and oxidizer tanks.

0726 GMT (3:26 a.m. EDT)

Activation of the rocket's guidance control system is starting.

0725 GMT (3:25 a.m. EDT)

Winds at the pad are just three knots from the northeast. That is a far cry from the blustery conditions experienced the past couple of days at Vandenberg. But it is very foggy at the launch site, which will hamper spectators' view of liftoff this morning.

0722 GMT (3:22 a.m. EDT)

T-minus 150 minutes and counting! The Terminal Countdown is now underway for today's launch of the Delta 2 rocket and the NOAA-N weather satellite at 1022:01 GMT from the SLC-2W pad at Vandenberg Air Force Base, California.

The pad area has been cleared of workers. However, a warning horn is being sounded at the complex as a precaution to alert any remaining personnel in the vicinity that they should leave immediately.

The pad clearing will allow the start of hazardous operations such as the pressurization of helium and nitrogen storage tanks inside the rocket's first and second stages, along with the second stage fuel and oxidizer tanks.

The countdown currently stands at T-minus 150 minutes. However, there are a pair of holds -- totaling 30 minutes in duration -- planned at T-minus 20 minutes and T-minus 4 minutes.

0714 GMT (3:14 a.m. EDT)

A poll of the launch team has verified everyone is "ready" to begin Terminal Count as scheduled this morning.

0707 GMT (3:07 a.m. EDT)

"Man stations for Terminal Count." The launch team members have been instructed to take positions at their consoles. A readiness poll will be performed in a few minutes to verify everyone is prepared to resume the countdown at the end of this scheduled hold at 0722:01 GMT.

0622 GMT (2:22 a.m. EDT)

T-minus 150 minutes and holding. The countdown has stopped for a pre-planned 60-minute built-in hold. Two more holds are scheduled into the count at T-minus 20 minutes and T-minus 4 minutes. Liftoff remains set for 1022 GMT today.

The Space Launch Complex-2 West pad has been cleared of workers following tonight's retraction of the mobile service tower, final ordnance connections and securing of the facility.

Over the next hour, the launch team will be polled to verify all stations are ready to proceed with the countdown. As Terminal Count begins an hour from now, pressurization of tanks on the first and second stages will occur, along with activation of the rocket's guidance system.

0550 GMT (1:50 a.m. EDT)

Launch controllers and the mission management team members are gathering at their consoles to oversee this morning's countdown and liftoff of the Boeing Delta 2 rocket from Vandenberg Air Force Base, California. The start of Terminal Count is about 90 minutes away.

0322 GMT (11:22 p.m. EDT Thurs.)

Launch is now seven hours away. Clocks are ticking down to the T-minus 150 minute mark where an hour-long hold starts at 0622 GMT. The Terminal Countdown will commence when clocks resume at 0722 GMT. Loading of the first stage with liquid oxygen starts at 0837 GMT.

The last hour of the countdown will be spent conducting engine steering tests, Range safety system checks and final arming. NOAA-N and the Delta rocket's systems transition from ground-fed power to internal batteries in the closing minutes.

A pair of final holds are built into the countdown at T-minus 20 minutes and T-minus 4 minutes, all leading to liftoff at 1022 GMT.

0209 GMT (10:09 p.m. EDT Thurs.)

Technicians have finished rolling the mobile service tower away from the rocket at Vandenberg's Space Launch Complex-2 West pad as the countdown gets underway for the overnight blastoff. There are no weather or technical problems being reported and the 12-story Boeing Delta 2 rocket stands ready to fly at 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT).

THURSDAY, MAY 12, 2005
2202 GMT (6:02 p.m. EDT)

ALL SYSTEMS GO! With the weather finally cooperating, mission managers have given approval to fuel the Delta rocket's first stage with 10,000 gallons of highly refined kerosene starting at 0000 GMT (8 p.m. EDT; 5 p.m. PDT) this evening. Following this operation, launch pad crews plan to retract the mobile service tower from around the rocket starting at 0045 GMT (8:45 p.m. EDT; 5:45 p.m. PDT).

Launch remains scheduled for 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT), with a 100 percent chance of acceptable weather conditions, forecasters say.

1645 GMT (12:45 p.m. EDT)

The launch weather team is optimistic that conditions will be acceptable later tonight for rollback of the mobile service tower and through the overnight hours for liftoff of the Delta rocket with the NOAA-N spacecraft. Winds are forecast to be within the 29-knot limit for tower retraction and well below the 26-knot launch constraint. You can read the forecast in detail here.

0035 GMT (8:35 p.m. EDT Wed.)

For the second straight night, remarkably gusty winds dogging California's Central Coast have caused space officials to postpone launching a civilian weather satellite atop a Boeing Delta 2 rocket.

This evening's blustery conditions with 30-knot gusts were unacceptable for retracting the mobile service tower enclosing the rocket on the Space Launch Complex-2 West pad at Vandenberg Air Force Base. Engineers have strict criteria that prevent the tower from being wheeled away from the Delta booster if winds approach the 29-knot limit.

The launch team faced the same situation Tuesday evening when winds were too strong to safely move the service gantry.

Although the winds ease after sunset, the weather conditions and the countdown timing that dictates when the tower has to be moved back have not synched up. For this particular launch, which targets liftoff at 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) to place the NOAA-N spacecraft into the proper orbit, the tower must be moved not later than 0300 GMT (11 p.m. EDT; 8 p.m. PDT).

Air Force meteorologists expect acceptable winds of around 20 knots for tower retraction on Thursday evening.

The weather outlook for Friday's predawn launch time calls for low clouds, fog and reduced visibility. However, those conditions are not constraints to launching, allowing forecasters to predict a zero percent chance of violating the liftoff weather rules.

0019 GMT (8:19 p.m. EDT Wed.)

SCRUB! The winds are not going to cooperate tonight, forcing officials to scrub the launch for 24 hours. The winds are expected to decrease over the next day. Liftoff is rescheduled for 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) Friday morning.

WEDNESDAY, MAY 11, 2005
2204 GMT (6:04 p.m. EDT)

Winds remain wickedly strong at Vandenberg this afternoon, with gusts at the launch pad being measured around the 29-knot limit imposed for service tower rollback during the countdown. Mission managers received a weather update a short time ago and will be briefed again at 0000 GMT to decide whether to proceed with loading the first stage with kerosene fuel at 0145 GMT as currently scheduled. Another weather update would occur around 0200 GMT to determine if it is possible to retract the tower soon thereafter.

1740 GMT (1:40 p.m. EDT)

With a cautious eye still watching the winds, the launch team is preparing for rollback of the mobile service tower and counting down to the overnight liftoff of the newest polar-orbiting weather satellite aboard a Delta 2 rocket.

The first launch opportunity was cancelled last night because strong winds at Vandenberg Air Force Base made retraction of the service gantry too dangerous. The latest forecast predicts the winds will be slightly better today, but still very close to the allowable limit.

"Vandenberg is currently under the influence of high pressure building in from the west. The system that allowed an enhanced pressure gradient and subsequent gusty winds yesterday afternoon has moved further east but we will expect gusty winds this afternoon approaching tower roll constraints," the launch weather team said today.

The outlook calls for northwesterly winds gusting to 28 knots. The limit for tower rollback is 29 knots.

The winds are expected to subside after sunset, Air Force meteorologists say, and by the 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) liftoff time, winds will become more northerly with maximum gusts of 15-20 knots. The launch time wind constraint is 26 knots.

A weather briefing is scheduled for 2130 GMT (5:30 p.m. EDT; 2:30 p.m. PDT) to determine if conditions appear promising for tower rollback. That would be followed a couple of hours later with fueling the rocket's first stage with kerosene propellant. The actual move of the tower is expected around 0100 GMT (9 p.m. EDT; 6 p.m. PDT) or later.

0029 GMT (8:29 p.m. EDT Tues.)

SCRUB! With a strong, persistent wind that makes retracting the launch pad service tower too risky tonight, officials have decided to postpone liftoff of the NOAA-N weather satellite aboard the Boeing Delta 2 rocket.

The launch has been pushed back one day. A fresh countdown will target liftoff at 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) Thursday morning.

Roaring winds were gusting as high as 36 knots at the Vandenberg Air Force Base, Calif., launch pad this afternoon. But forecasters expect the conditions to improve over the next 24 hours, with winds 25 knots or less expected Wednesday evening when crews are supposed to move the mobile service tower away from the rocket for the second launch attempt.

Meteorologists closely monitor the winds to ensure the 29-knot limit is not broken when the tower is slowly wheeled back from the rocket. The structure is used to assemble the rocket stages on the pad, provide access for workers and completely enclose the vehicle from the elements. It must be retracted several hours before liftoff time so technicians can secure the pad for the final countdown.

Aside from the weather troubles, NASA says no technical problems are being addressed at this time.

TUESDAY, MAY 10, 2005
2205 GMT (6:05 p.m. EDT)

A weather briefing was just held at Vandenberg Air Force Base for launch managers to assess the current and forecast conditions for tonight's countdown. Strong winds at the launch site continue to be the main concern this evening.

The problem is winds being too gusty to safely retract the mobile service tower from around the Delta 2 rocket later tonight. Air Force meteorologists are predicting winds of 27 to 35 knots. The limit imposed during tower rollback is 29 knots.

Another weather update has been scheduled for 0000 GMT (8 p.m. EDT; 5 p.m. PDT) in advance of filling the rocket's first stage fuel tank with highly refined kerosene. If the winds ease, the tower could be moved sometime after 0130 GMT.

The winds are predicted to decrease overnight, yet still pose a concern for violating the 26-knot limit in place at launch time.

For now, liftoff remains targeted to occur at 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) Wednesday morning.

0401 GMT (12:01 a.m. EDT)

Blustery winds howling across California's Central Coast are threatening to interfere with launch countdown preparations for Wednesday morning's liftoff of the two-stage Boeing Delta 2 rocket carrying the NOAA-N weather satellite.

"There's some challenges. We expect the wind to be pretty high," NASA launch director Omar Baez said.

Mission managers held the Launch Readiness Review on Monday, affirming plans to proceed with work leading to liftoff at 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) from Vandenberg Air Force Base. However, the weather outlook is a source of concern.

Air Force meteorologists are predicting north-northwesterly winds blowing at 35 knots Tuesday evening when the protective mobile service tower is supposed to retract from around the Delta 2 rocket at the SLC-2W launch pad. Winds must be below 29 knots to safely wheel the gantry into its launch position.

Officials will receive a briefing from the weather team at 2130 GMT (5:30 p.m. EDT; 2:30 p.m. PDT) to determine when conditions could permit tower rollback. Meanwhile, technicians plan to load the rocket's first stage with its 10,000-gallon supply of kerosene fuel about 2.5 hours later while the vehicle is still shrouded by the service structure. This early fueling operation acts to weight down the rocket once the tower is moved away later, when the booster is left fully exposed to the wind.

If the winds cooperate, tower retraction is supposed to commence around 0130 GMT (9:30 p.m. EDT; 6:30 p.m. PDT). Rollback could be delayed an hour or two without impacting the launch attempt. But should the weather remain an obstacle around 0300 GMT, officials could decide to call a scrub.

"We'll know by then if we're going to even attempt," Baez said.

The weather worry doesn't end with tower rollback. Although the winds are expected to gradually ease overnight, meteorologists say there is a 40 percent chance that the conditions will be unacceptable at liftoff time. The forecast calls for winds of 20 to 25 knots, and the highest allowable wind conditions at launch is 26 knots.

"As an end-user of the weather data that comes this satellite, I'm keenly interested in making sure we see a good on-orbit placement," said Capt. Paul Lucyk, the launch weather officer from the 30th Weather Squadron at Vandenberg.

"On the night of launch, my weather team and I will be monitoring many weather constraints to ensure the safety of flight, as well as mission assurance to ensure the vehicle gets on-orbit.

"I'll monitor several weather constraints to ensure we protect against natural and triggered lightning, as well as constraints for precipitations -- we don't want to fly through any potentially damaging water droplets or ice crystals. I'll be looking for acceptable ground winds for tower roll, fueling, as well as liftoff. That's going to be our biggest concern at this time -- the winds right now the way they look, that's probably going to be the trickiest part of the forecast."

Should the mission slip 24 hours, the forecast improves for a Wednesday night tower rollback and Thursday predawn blastoff. The launch time would remain the same.

MONDAY, MAY 9, 2005
1600 GMT (12:00 p.m. EDT)

The official weather forecast has been issued for Wednesday's planned launch attempt. Meteorologists are worried about strong winds posing a problem for retracting the launch pad's mobile service tower Tuesday evening and the gusty conditions continuing overnight at liftoff time. See the full forecast here.

0401 GMT (12:01 a.m. EDT)

After a relatively quiet weekend resting, launch crews will spend Monday running tests and prepping the pad for Wednesday's predawn liftoff of the NOAA-N weather satellite aboard the Boeing Delta 2 rocket from Vandenberg Air Force Base, California.

Launch will be possible during a 10-minute window that opens at 1022:01 GMT (6:22:01 a.m. EDT; 3:22:01 a.m. PDT) for the 65-minute rocket flight to deliver this newest weather-watcher into orbit.

"Launch preparations continue on schedule at Space Launch Complex-2," NASA spokesman George Diller said Sunday. "All work is completed to date, so Sunday has only minimal work scheduled before picking up with preliminary countdown activities on Monday."

Items on Monday's to-do list include checks of the rocket's ignition and Range Safety systems, posting an update to the vehicle's guidance system program, charging the satellite's batteries, filling of the pad's liquid nitrogen supply tank and initial work for Tuesday evening's rollback of the mobile service tower from around the Delta 2.

Also Monday, senior mission managers will gather for the Launch Readiness Review to give the formal approval to enter the countdown. A pre-launch news conference follows at 2000 GMT (4 p.m. EDT; 1 p.m. PDT).

The early weather outlook predicts a 30 or 40 percent chance of violating the launch rules, Diller said.

SUNDAY, MAY 8, 2005

Taking the pulse of our planet's health and detecting clues needed for weather forecasts have been the chief tasks for Earth-orbiting weather observatories over the past four decades, and that legacy will be extended this week when the latest spacecraft blasts off from California.

The NOAA-N satellite is slated for liftoff at 1022 GMT (6:22 a.m. EDT; 3:22 a.m. PDT) from Space Launch Complex-2 West at Vandenberg Air Force Base atop a Boeing-built Delta 2 rocket.

"When it launches, NOAA-N will not only be our eyes above the Earth, but our eyes into the future," said Gregory Withee, assistant administrator for the NOAA Satellite and Information Service.

Read our full launch preview story.