NASA's Lunar Reconnaissance Orbiter has transmitted its first images since reaching the moon on June 23. The spacecraft's cameras have returned images of a region in the lunar highlands south of Mare Nubium, or the Sea of Clouds.

See the photo release here.

The Lunar Reconnaissance Orbiter reached its commissioning orbit around the Moon the today, a 31 by 199 km (19 by 124 mile) orbit inclined 90.2 degrees.

Since being captured by the Moon's gravity on Tuesday, the LRO spacecraft has completed four additional engine firing that methodically shrank the altitude much closer to the lunar surface.

LRO will remain in this orbit while its systems and instruments are checked out. It's circular mapping orbit of about 50 km (31 miles) will be obtained in about two months.

Four-and-a-half days after launch, NASA's $504 million Lunar Reconnaissance Orbiter fired its main thrusters for 40 minutes early Tuesday, successfully braking into an initial elliptical orbit around the Moon.

Read our launch story here.

The close approach by LCROSS occurred at 6:30:33 a.m. EDT. The spacecraft is entering a so-called Lunar Gravity Assist, Lunar Return Orbit (LGALRO) around the Earth to prepare for impact with the Moon's south pole on October 9. Each of the LGALRO orbits around the planet last approximately 37 days.

The lunar orbit insertion burn by LRO has resulted in a 220 by 3,100 km (137 by 1,926 mile) orbit around the Moon, according to Craig Tooley, the LRO project manager.

Four further burns over the next few days will reach the mission's planned "commissioning orbit" of 30 by 216 km (18.5 by 134 miles) on Saturday. The circular mapping orbit of 50 km (31 miles) will be reached in about two months.

Meanwhile, the LCROSS spacecraft has just passed periselene, its closest approach to the Moon during the planned lunar swingby. The craft and attached Centaur flew 3200 km (1988 miles) above the lunar surface.

The duo will stay coupled together for four months as they make incredibly long orbits around the Earth. The looping orbits will extend outward past the Moon's distance, then swing back to close proximity to the home planet, setting the stage for impact into the lunar south pole on October 9.

Today's close encounter is used to change LCROSS's Earth orbit into a polar one.

"The LOI went like clockwork," says Craig Tooley, the LRO project manager says.

He also says tracking data already shows the spacecraft is where it's supposed to be.

"All thrusters have stopped," the flight director announced a few moments ago.

"All stations, this is Flight. Congratulations on a successful LOI. LRO has returned NASA to the Moon."

Burn complete! Four-and-a-half days after leaving Earth, NASA's Lunar Reconnaissance Orbiter has reached its capture orbit around the Moon.

About 80 percent into the burn. Guidance, navigation and control reports all remains nominal.

The burn is calculated to conclude at 6:26:28 a.m. EDT, the project says.

LRO is just 280 km (174 miles) above the Moon, its closest point during the burn.

Pressure and temperature readings from the spacecraft's thrusters still look normal, Mission Control says.

The so-called stable capture point has been achieved, meaning LRO can reach its lunar orbit even if something halts the burn now.

Now half way through this 40-minute burn.

"The burn is going great," says Laurie Leshin, Goddard deputy director for Science and Technology.

All continues to go well. LRO is less than 600 km (372 miles) above the Moon.

This burn is designed to put the LRO spacecraft into a 200 by 3,000 km (125 by 1,865 mile) orbit around the Moon. Four further burns are planned over the next few days to reach the mission's planned "commissioning orbit" of 30 by 216 km (18.5 by 134 miles) on Saturday. The circular mapping orbit of 50 km (31 miles) will be reached in about two months.

This burn is designed to put the LRO spacecraft into a 200 by 3,000 km (125 by 1,865 mile) orbit around the Moon. Four further burns over the next few days to reach the mission's planned "commissioning orbit" of 30 by 216 km (18.5 by 134 miles) on Saturday. The circular mapping orbit of 50 km (31 miles) will be reached in about two months.

Thrusters all look nominal, officials report.

"Everything looks nominal," flight controllers report.

Ignition! The four main thrusters on the bottom of the spacecraft have been lit for this 40-minute firing to brake into orbit around the Moon.

One minute away from the burn's start.

All systems aboard the LRO spacecraft have been configured for the lunar orbit insertion burn, or LOI. A few hours ago, the craft performed a brief engineering test burn in preparation for the big event.

"This is LRO's most critical activity that we've been planning for," says Cathy Peddie, LRO deputy project manager. "The lunar orbit insertion burn is what we used to change LRO's velocity. As LRO is right now falling towards the Moon, this burn will help us change its velocity so that the Moon will be able to capture LRO."

"The spacecraft is ready. My team is ready. GO LRO," writes Craig Tooley, the Lunar Reconnaissance Orbiter project manager.

The Lunar Reconnaissance Orbiter is nearing the Moon for its orbit insertion maneuver today. The craft's engines will be fired for 40 minutes starting around 5:47 a.m. EDT. Watch this page for live updates during the critical burn.

Meanwhile, the LCROSS spacecraft will make a swingby of the Moon today to adjust its elongated Earth orbit. The closest approach occurs around 6:30 a.m. EDT.

An Atlas 5 rocket thundered to life and majestically streaked into space Friday, boosting two NASA spacecraft toward the moon for an ambitious $583 million mission to scout out landing sites for future manned missions and to search for evidence of hidden ice near its frigid poles.

Read our launch story here.

More launch pictures can be viewed in the gallery.

LCROSS and Centaur are now more than 30,000 miles from Earth, speeding toward the moon at 8,000 mph.

The duo will using a swingby of the Moon on Tuesday to enter into a highly elliptical orbit around the Earth and prepare for the lunar south pole impact on October 9 around 7:30 a.m. EDT.

"After LRO separates, normally the Atlas rocket is now waste, it's done with its mission. But we hang on to it and we do a lunar gravity assist swinging by the moon and never actually enter into a lunar orbit. We're actually in an Earth orbit. That's how we can set it up for an impact trajectory about 120 days later," Dan Andrews, LCROSS project manager, said in a pre-launch interview.

"We have to make the specific crater decision 30 days before impact. It's nice that we can actually decide which crater we're going to hit after we've launched."

About 9 hours and 40 minutes before the impact, LCROSS will separate from the Centaur. The satellite will perform a small braking maneuver to create a four-minute separation from the Centaur in order to watch the rocket smack the Moon and observe the debris cloud in search for evidence of water ice in premanently shadowed craters at the lunar south pole.

Confirmation has been received that the Centaur upper stage has transferred control of the stack to the LCROSS shepherding spacecraft. LCROSS will guide the Centaur for the remainder of the four-month journey to the impact site on the lunar south pole.

This officially ends today's launch of the Atlas 5 rocket, successfully completing the vehicle's 16th flight since debuting in 2002. The next Atlas 5 mission is scheduled for mid-August.

"In the 1960s, the Centaur was the first upper stage vehicle ever built with the lifting power to reach the moon and was specifically developed for lunar and planetary surveying," said Vernon Thorp, United Launch Alliance's NASA program manager.

"Centaur was used to help scout the first Apollo landing sites. Using it now to find water allowing astronauts to work on the moon for long periods of time in the future is adding another significant chapter to the Centaur's history of supporting NASA's human spaceflight program," Thorp said.

NASA confirms the LCROSS spacecraft has successfully powered up and engineers are receiving telemtry from the probe. LCROSS will take over control of the stack around 9:30 p.m. EDT.

More launch pictures can be viewed here.

The Lunar Reconnaissance Orbiter has deployed its power-generating solar array and high-speed communications antenna.

We have posted photos of the launch taken from the Kennedy Space Center press site here.

While Lunar Reconnaissance Orbiter flies away on its own, LCROSS will remain with the Centaur. Special procedures to deplete and expel residual fuel from the upper stage will be performed over the next couple of hours this evening, leading to the official transfer of control from the rocket to the LCROSS spacecraft about four hours after launch.

The duo will stay coupled together for four months as they make incredibly long orbits around the Earth. The looping orbits will extend outward past the Moon's distance, then swing back to close proximity to the home planet, setting the stage for impact into the lunar south pole on October 9.

"All's well so far. We just accomplished LRO separation, which was obviously a great milestone. We wish LRO and our friends at Goddard Space Flight Center good luck on their mission. We look forward to the returns on it," said NASA launch director Chuck Dovale.

"Obviously we're not done. We've got a few more hours more to go for LCROSS. At about four hours after launch, we should be seeing the handover from the Centaur-led, ULA-led mission over to the Ames project and LCROSS. We're looking forward to that, but we have a few hours to go.

"But all appears well for LRO and we wish them luck."

The Lunar Reconnaissance Orbiter will reach the Moon on Tuesday morning at 5:43 a.m. EDT (0943 GMT) and ignite its engines for a nail-biting maneuver that amounts to a make-or-break moment in the $504 million mission.

The engine firing slows the spacecraft's speed and allows LRO to enter into orbit around the Moon. If all goes well, the satellite should swoop into an elliptical "commissioning orbit" of 30 by 216 kilometers (18.5 by 134 miles).

In a pre-launch interview, Craig Tooley, the LRO project manager, briefly describes what's upcoming for the spacecraft:

"We come off the launch vehicle and our very first concern is as soon as we're free and the breakwires and switches go, we begin to try to acquire commanding from the ground. We deploy the solar array, so we can get power positive. We deploy our high-gain antenna, although we have some flexibility with that because we have omni (antennas).

"We begin tracking and will do a mid-course correction to trim out whatever the Atlas gave us, and then a few days later we start doing some test burns of our larger rocket engines in preparation for this lunar orbit insertion. So basically we'll check them out so we'll know how they're actually performing before we commit to this big burn."

T+plus 44 minutes, 45 seconds. SPACECRAFT SEPARATION! The Centaur upper stage has deployed the Lunar Reconnaissance Orbiter on its direct trajectory for the Moon.

The instrument-laden spacecraft is NASA's trailblazer for future human missions back the lunar surface. LRO will create detailed maps of the terrain, plot out potential landing sites, identify natural resources that could be exploited and characterize the radiation conditions that astronauts can expect.

T+plus 34 minutes. Centaur is in the spacecraft deploy position.

T+plus 43 minutes, 20 seconds. Centaur has hit the planned orbital parameters.

T+plus 42 minutes, 30 seconds. Centaur is maneuvering itself to the proper orientation for releasing LRO.

T+plus 41 minutes, 57 seconds. MECO 2. Main engine cutoff confirmed. Centaur has completed its second burn. Release of the LRO payload from the rocket is expected in about three minutes.

T+plus 40 minutes. About two minutes left in this burn by the Centaur's single Pratt & Whitney Rocketdyne RL10 engine.

T+plus 39 minutes, 20 seconds. Centaur is operating correctly. Battery voltages and tank pressures are as expected. The vehicle is stable and body rates are normal.

T+plus 38 minutes. The rocket is flying over the Indian Ocean now.

T+plus 37 minutes, 30 seconds. Engine is burning well for the second time in this launch.

T+plus 36 minutes, 59 seconds. Ignition and full thrust! The Centaur has begun the firing that will send the Lunar Reconnaissance Orbiter to the Moon.

T+plus 32 minutes. Centaur systems are reported normal during this coast period.

T+plus 27 minutes. The quiet orbital coast continues. The Tracking and Data Relay Satellite system is following the vehicle and transmitting telemetry back to the launch site.

T+plus 20 minutes. A map of the rocket's planned ground track for today's launch is available here.

T+plus 17 minutes, 30 seconds. The rocket is performing its turn to the proper position for the next engine firing.

T+plus 15 minutes, 50 seconds. The parking orbit parameters are right on the money.

T+plus 14 minutes, 30 seconds. This initial circular orbit is 100 nautical miles in altitude, inclined 28.5 degrees to the equator.

T+plus 14 minutes, 6 seconds. MECO 1. Centaur's main engine has shut down following its first burn today, achieving a preliminary orbit around Earth. The rocket will coast in this orbit for about 24 minutes before the RL10 engine re-ignites.

T+plus 13 minutes. The vehicle is flying right on course. Traveling over 16,000 mph now.

T+plus 12 minutes. The RL10 continues to perform well, burning liquid hydrogen and liquid oxygen propellants. Tank pressures also look good.

T+plus 11 minutes. Centaur is 118 miles in altitude and 1,620 miles downrange, traveling well over 14,000 mph.

T+plus 9 minutes, 25 seconds. Centaur is 124 miles in altitude and 1,274 miles downrange, traveling at 13,740 mph.

T+plus 9 minutes. A little more than five minutes remain in this burn of Centaur.

T+plus 8 minutes, 45 seconds. All systems reported stable as the Centaur fires to reach an initial Earth orbit.

T+plus 7 minutes, 55 seconds. Passing 120 miles in altitude.

T+plus 7 minutes, 15 seconds. Speed now exceeding 12,000 mph.

T+plus 6 minutes, 25 seconds. Centaur is 105 miles in altitude and 618 miles downrange.

T+plus 5 minutes, 15 seconds. Centaur engine readings look good as this 10-minute burn continues.

T+plus 4 minutes, 32 seconds. The two-halves of the Atlas 5 rocket nose cone encapsulating the spacecraft have separated.

T+plus 4 minutes, 24 seconds. Centaur has ignited! The RL10 engine is up and running at full thrust.

T+plus 4 minutes, 18 seconds. The Atlas 5's Common Core Booster first stage has been jettisoned, and the Centaur upper stage's liquid hydrogen and liquid oxygen systems are being readied for engine start.

T+plus 4 minutes, 8 seconds. BECO. Booster Engine Cutoff is confirmed as the RD-180 powerplant on the first stage completes its burn. Standing by to fire the retro thrusters and separate the spent stage.

T+plus 3 minutes, 40 seconds. The RD-180 main engine continues to fire normally, burning a mixture of highly refined kerosene and liquid oxygen.

T+plus 3 minutes, 10 seconds. The boost phase roll maneuver is underway.

T+plus 2 minutes, 45 seconds. RD-180 is performing well as the rocket climbs away from the planet.

T+plus 2 minutes. Atlas is 11.3 miles in altitude, 9.9 miles downrange from the launch pad, traveling at 2,400 mph already.

T+plus 85 seconds. Mach 1.

T+plus 70 seconds. All systems reported stable.

T+plus 60 seconds. One minute into NASA's lunar voyage.

T+plus 50 seconds. The vehicle is disappearing into the clouds.

T+plus 30 seconds. The Atlas 5 rocket is thundering away from Cape Canaveral on the power of the RD-180 main engine carrying a robotic scout to reconnoiter the Moon like never before and a sleuth that will dig into a tantalizing mystery at the lunar south pole.

LIFTOFF! Liftoff of the Atlas 5 rocket launching NASA's robotic expedition that will pave the way for mankind's return to the Moon. And the vehicle has cleared the tower!

T-minus 20 seconds. "Go Atlas" and "Go Centaur" was just called by launch team during a final status check.

T-minus 40 seconds. Centaur's liquid oxygen and liquid hydrogen tanks are stable at flight pressures.

T-minus 1 minute. Now 60 seconds from launch of the Lunar Reconnaissance Orbiter and LCROSS spacecraft bound for the Moon.

T-minus 90 seconds. The flight termination safety system has been armed.

T-minus 1 minute, 50 seconds. Liquid oxygen and liquid hydrogen propellant topping to the Centaur upper stage is being secured.

T-minus 1 minute, 55 seconds. The launch sequencer has been commanded to start.

T-minus 2 minutes. The Atlas first stage and Centaur upper stage are now switching from ground power to internal batteries.

T-minus 2 minutes, 30 seconds. The first stage RP-1 kerosene fuel tank and the liquid oxygen have stepped up to proper flight pressure levels.

T-minus 3 minutes. The Atlas first stage liquid oxygen replenishment is being secured so the tank can be pressurized for launch.

T-minus 3 minutes, 50 seconds. The ground pyrotechnics have been enabled.

T-minus 4 minutes and counting. Clocks have resumed for the final minutes of this afternoon's countdown to launch the Atlas 5 rocket carrying the LRO and LCROSS spacecraft. Liftoff is set to occur at 5:32 p.m.

Countdown clocks will resume in one minute. Still targeting a launch to the Moon at 32 minutes past the hour.

Polling of the team by Atlas launch conductor Ed Christiansen just occurred. All systems are reported "go" to continue with the countdown for liftoff at 5:32 p.m.

The launch team is being polled for a "go" or "no go" to proceed with the count.

The LRO and LCROSS spacecraft are running on internal power and ready for launch.

Launch is now just 10 minutes away. Here's a look at some stats about today's mission. This will be:

• The 19th Atlas rocket launched to the Moon
• The eighth lunar flight of the Centaur upper stage
• The 16th launch of an Atlas 5 vehicle since 2002
• The 15th Atlas 5 to occur from Cape Canaveral
• The seventh Atlas 5 to fly in the 401 configuration
• The eighth Atlas 5 under United Launch Alliance
• NASA's third use of the Atlas 5 family

The spacecraft are switching to internal battery power for launch.

NASA launch director Chuck Dovale has polled the agency's management team and given approval to proceed with the final countdown to liftoff.

Weather is go! The Air Force has just declared all conditions are now within limits for launch at 5:32 p.m. EDT.

Now 15 minutes away from the scheduled launch time. It is the last opportunity to launch within today's lunar window. Still watching and waiting on the weather.

Weather officer says conditions could clear and become acceptable in about 10 minutes, allowing for the launch to happen at 5:32 p.m. EDT.

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The current plan calls for the launch team readiness poll to be conducted at 5:25 p.m., followed by resumption of the countdown at 5:28 p.m. and liftoff at 5:32 p.m. EDT, weather permitting.

If the liftoff does not occur today, NASA has another lunar launch window tomorrow and one on Saturday evening. But officials have their fingers crossed that the troublesome clouds and lightning potential currently delaying the launch will clear out of the area in time for liftoff at 5:32 p.m. EDT this afternoon.

DELAY. The thunderstorms around the launch site will not permit an on-time launch of the Atlas 5 rocket at 5:12 p.m. EDT. Mission managers are looking to reschedule the liftoff for today's last launch opportunity at 5:32 p.m. EDT, if the weather improves.

The launch team continues to watch the weather situation here at the Cape.

T-minus 4 minutes and holding. The countdown has entered the planned 20-minute hold to give the launch team a chance to review all systems before pressing ahead with liftoff. This hold is twice as long as usual, given the limited launch slots available for this lunar window. If launch doesn't happen at exactly 5:12 p.m., the liftoff will slip to the next opportunity at 5:22 p.m. or the day's final one at 5:32 p.m. EDT.

The first stage liquid oxygen tank and Centaur's liquid oxygen and liquid hydrogen tanks are reported at flight level.

T-minus 5 minutes. Standing by to go into the final built-in hold.

The fuel-fill sequence for the first stage main engine has been completed.

The official launch time outlook calls for scattered clouds at 2,500 and 8,000 feet, a broken deck at 25,000 feet, isolated thunderstorms, 7 miles of visibility, northwesterly winds from 320 degrees at 12-16 knots and a temperature of 84-85 degrees F.

The chances of weather conditions allowing the Atlas rocket to launch today have dropped to just 30 percent, forecasters now say.

At present, the lightning and cumulus cloud rules remain "no go" for launch. The anvil cloud rule and the field mills that measure the electrical potential in the air are now being violated as well.

Pre-launch check of the rocket's safety system has been completed.

Forty minutes from liftoff. The countdown clocks are heading to the T-minus 4 minute mark where a planned 20-minute hold will occur. Launch of Atlas 5 remains scheduled for 5:12 p.m. EDT, however the weather is "no go" at the current time due to lightning concerns and clouds.

The launch team is going through normal post-fueling valve and system checks.

Now 60 minutes from liftoff. Fueling of the Atlas rocket with cryogenic liquid oxygen and liquid hydrogen is proceeding as planned and activities remain on schedule for a liftoff at 5:12 p.m. EDT. Local thunderstorms are the only concern right now.

If the weather or a technical problem prevents an on-time launch at 5:12 p.m. EDT, there are two later opportunities available at 5:22 and 5:32 p.m. EDT.

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The liquid hydrogen tank in the Centaur upper stage just reached the 97 percent level. Topping is now beginning.

Fast-filling of the first stage liquid oxygen tank has been completed. Topping mode is now underway.

The Centaur liquid hydrogen tank is 70 percent loaded so far. The cryogenic propellant will be consumed with liquid oxygen by the stage's Pratt & Whitney-made RL10 engine.

The first stage liquid oxygen tank is 90 percent full now.

The current weather conditions are now violating the launch rules for lightning and cumulus clouds. The weather team expects this "no go" status to last an hour. It's going to be a real-time call if the weather will improve soon enough for launch at 5:12 p.m.

The first stage liquid oxygen tank is a little over three-quarters full.

Centaur's liquid hydrogen tank is 20 percent full already.

A low-level lightning advisory for the Cape area that includes Complex 41 is expected to be issued shortly.

Chilldown of the liquid hydrogen system has been accomplished. The launch team has received the "go" to begin filling the Centaur upper stage with the supercold fuel.

First stage liquid oxygen tank is passing the 40 percent mark. Chilled to Minus-298 degrees F, the liquid oxygen will be used with RP-1 kerosene by the RD-180 main engine on the first stage during the initial four-and-a-quarter minutes of flight today. The 25,000 gallons of RP-1 were loaded into the rocket during the first countdown a couple of weeks ago.

Now 90 minutes from liftoff.

The Centaur engine chilldown sequence is being initiated.

Upper stage liquid oyxgen has reached flight level.

The Centaur liquid oxygen tank reached the 95 percent level. The topping off process is starting now.

The Centaur liquid oxygen tank is 90 percent full.

The first stage liquid oxygen loading is switching from slow-fill to fast-fill mode.

The chilldown conditioning of liquid hydrogen propellant lines at Complex 41 is starting to prepare the plumbing for transferring the Minus-423 degree F fuel into the rocket. The Centaur holds about 13,000 gallons of the cryogenic propellant.

The launch weather officer says the thunderstorms sliding moving southward over Central Florida are expected to cause a "red" on the weather board in about 15 minutes. That condition is likely to last an hour, NASA says.

Half of the Centaur liquid oxygen tank has been filled so far.

The chilldown conditioning of the systems for the first stage liquid oxygen tank have been completed. And a "go" has been given to begin pumping supercold liquid oxygen into the Atlas 5's first stage.

The Common Core Booster stage's liquid oxygen tank is the largest tank to be filled today. It holds about 50,000 gallons of cryogenic oxidizer for the RD-180 main engine.

The Centaur liquid oxygen tank has reached the 30 percent level.

Filling of the Centaur upper stage with about 4,300 gallons of liquid oxygen has begun at Cape Canaveral's Complex 41 following the thermal conditioning of the transfer pipes.

The liquid oxygen -- chilled to Minus-298 degrees F -- will be consumed during the launch by the Centaur's single RL10 engine along with liquid hydrogen to be pumped into the stage a little later in the countdown. The Centaur will perform a pair of firings today to send LRO and LCROSS on their way toward the Moon.

The Centaur liquid oxygen pad storage area has been prepped. The next step is conditioning the transfer lines, which is now beginning to prepare the plumbing for flowing the cryogenic oxidizer.

T-minus 120 minutes and counting! The launch countdown is continuing for today's flight of the Atlas 5 rocket to dispatch the Lunar Reconnaissance Orbiter and LCROSS spacecraft to the Moon.

Clocks have one more built-in hold planned at T-minus 4 minutes. That pause will last 20 minutes during which time the final "go" for launch will be given. All remains targeted for liftoff at 5:12 p.m. EDT from Cape Canaveral's Complex 41.

In the next couple of minutes, chilldown thermal conditioning of the mobile launch platform upon which the rocket stands will begin. This is meant to ease the shock on equipment when supercold cryogenic propellants start flowing into the rocket.

All console operators in the Atlas Spaceflight Operations Center reported a "ready" status during the pre-fueling poll just completed by the launch conductor. The ULA launch director voiced his approval as well. Loading of cryogenic liquid oxygen and liquid hydrogen into the Atlas 5 rocket will be getting underway a short time from now.

Atlas launch conductor Ed Christiansen is briefing his team on procedures before entering into the final two hours of the countdown. A readiness check of the team members is next.

NASA launch director Chuck Dovale has polled the agency's management team and given approval to proceed with fueling the Atlas 5 rocket.

T-minus 2 hours and holding. The countdown has just entered the first of two planned holds over the course of the afternoon that will lead to the 5:12 p.m. EDT launch of the Atlas-Centaur rocket. This initial pause lasts 30 minutes, giving the team some margin in the countdown timeline to deal with technical issues or any work that is running behind. The final hold is scheduled to occur at T-minus 4 minutes and will last for 20 minutes.

Workers have cleared the Complex 41 pad and the blast danger area in advance of this afternoon's propellant loading and launch of the Atlas 5 rocket.

The hold-fire checks have been performed to ensure safety officers have the capability of halting the countdown if a problem occurs.

None of the weather rules are being violated at this time. There are some typical summertime thunderstorms that have popped up inland. For the planned 5:12 p.m. EDT launch, the forecasters still predict a 60 percent chance of acceptable conditions due to the thunderstorms in the area today.

There are no problems being worked in the countdown as the launch team marches through pre-flight testing of vehicle systems, NASA reports.

We have posted a collection of photos shot this morning at the launch pad. You can see the images here.

Good day from the Kennedy Space Center in Florida where across the river at Complex 41 the countdown is underway for the launch of NASA's Lunar Reconnaissance Orbiter and the LCROSS impactor mission aboard an Atlas 5 rocket.

NASA says pre-launch activities are proceeding well toward the planned 5:12 p.m. EDT liftoff today.

Our live call of the countdown will begin at 2 p.m.

A United Launch Alliance Atlas 5 rocket will shoot for the Moon today, blasting off from the Cape Canaveral Air Force Station at 5:12 p.m. EDT.

Countdown clocks will start ticking at 10:02 a.m. EDT as the launch team begins powering up the rocket to commence standard pre-flight tests. Over the next few hours, final preps for the Centaur's liquid oxygen and liquid hydrogen systems will be performed, along with a test of the rocket's guidance system and the first stage propulsion and hydraulic preps, internal battery checks and testing of the C-band system used to track the rocket as it flies downrange, plus a test of the S-band telemetry relay system. The Complex 41 site will be cleared of all personnel at 2:07 p.m.

A planned half-hour hold begins at 2:22 p.m. when the count reaches T-minus 120 minutes. Near the end of the hold, the team will be polled at 2:49 p.m. to verify all is in readiness to start fueling the rocket for launch.

Supercold liquid oxygen begins flowing into the Centaur upper stage around 3:09 p.m., followed by the first stage filling around 3:22 p.m. Liquid hydrogen fuel loading for Centaur will be completed a short time later.

A final hold is scheduled at the T-minus 4 minute mark starting at 4:48 p.m. That 20-minute pause will give everyone a chance to finish any late work and assess the status of the rocket, payloads, Range and weather before proceeding into the last moments of the countdown.

There will be three precise launch times available for the liftoff to occur: 5:12 p.m., 5:22 p.m. and 5:32 p.m. EDT.

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A collection of beautiful photos showing the Atlas 5 rocket rolling out to the launch pad Wednesday is posted here.

On the pad! The Atlas 5 rocket has arrived at the Complex 41 pad for launch of NASA's robotic expedition to the Moon using two satellites to map and probe the lunar surface in unprecedented detail.

The two mobile trailers connected to the launching platform, which were part of the convoy during this morning's rollout, soon will be hooked up to power and communications systems at the pad. These trailers provide conditioned air to the payload and communications with the rocket during the rollout and the countdown. They are protected from the blast of launch by a concrete structure on the north-side of the platform.

Within the next hour, the auto couplers between the pad and platform will be engaged to route umbilical connections from the ground to the rocket for tomorrow's fueling of the booster with cryogenic propellants.

Later this afternoon, the undercarriages used to move the mobile platform will be disconnected and the "trackmobiles" pulled free.

Ground crews will secure the rocket for a peaceful evening, which should be the vehicle's final night on the planet. The launch countdown commences at 10:02 a.m. EDT tomorrow, leading toward a liftoff at 5:12 p.m. EDT.

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Air Force meteorologists are predicting a 60 percent chance of acceptable conditions at Thursday's 5:12 p.m. EDT launch time. Clouds and lightning are the main concerns for violating the launch weather rules.

The outlook calls for scattered clouds at 3,000 and 10,000 feet, a broken deck at 25,000 feet, isolated showers, 7 miles of visibility, northeasterly winds from 060 degrees at 14-18 knots and a temperature of 84-85 degrees F.

"High pressure remains suppressed to the south with a weak surface trough extending from the Carolinas into Louisiana. Ample moisture and upper level impulses coming across the upper level ridge in the Gulf of Mexico will aid in afternoon and evening thunderstorm development through the week. Thunderstorms are expected to persist late into the evening," forecasters reported today.

"For MLP roll, light southwesterly winds become easterly by late morning. The seabreeze will act to focus developing showers and thunderstorms by late morning to early afternoon, but not expected to impact MLP roll.

"On launch day, westerly surface winds become easterly by early afternoon with the seabreeze development. An upper level disturbance transits the area increasing the thunderstorm threat. Steering level winds begin transitioning to favor slow migration of thunderstorms to the west. The primary concerns for launch day are anvil clouds, cumulus clouds and lightning.

"In the event of a 24 hour delay, the seabreeze will act to focus initial thunderstorm development by late morning to early afternoon with a slow migration to the West. Steering level winds and anvil level wind flow become more favorable for transporting thunderstorms and anvil to the West away from East coast. The primary concerns for a 24 hour delay are lightning, cumulus clouds, and anvil clouds."

The odds of acceptable weather on Friday, if the launch slips 24 hours for some reason, is 70 percent.

Rollout begins! The United Launch Alliance Atlas 5 rocket that will send NASA's Lunar Reconnaissance Orbiter and the LCROSS spacecraft to the Moon just began a slow half-hour drive from the 30-story Vertical Integration Facility to Cape Canaveral's Complex 41 pad for Thursday afternoon's liftoff.

A pair of specially-made "trackmobiles" are carrying the Atlas 5 rocket's 1.4-million pound mobile launching platform along rail tracks for this 1,800-foot trip.

The two-stage rocket was put together inside the Vertical Integration Facility back in April. The two payloads were mounted atop the vehicle at the end of May. The Atlas 5 is designed to spend minimal time at the launch pad, which does not include a service gantry like other rockets.

The sun is up and the doors on the Vertical Integration Facility are sliding open for this morning's rollout of the Atlas 5 rocket to Cape Canaveral's Complex 41 launch pad.