SpaceX says the GLACIER freezers stowed inside the Dragon spacecraft never lost power after splashdown today, dodging a concern that intrusion of sea water could flood electrical boxes and disrupt power to the units.

After the last Dragon capsule splashed down in October, the power box providing electricity to a GLACIER freezer with refrigerated blood and urine samples was inundated by sea water. The freezer lost power, but temperatures inside never reached critical limits, and the samples were not ruined.

SpaceX beefed up covers around the power boxes on this spacecraft.

Mission control in Houston just radioed the space station crew that the Dragon spacecraft has been hoisted onto a barge following an on-target splashdown in the Pacific Ocean.

Plans call for the capsule to reach the Port of Los Angeles within 30 hours of splashdown, where SpaceX will hand over sensitive biological samples to NASA. The spacecraft will then travel to SpaceX's development facility in McGregor, Texas, where the rest of Dragon's payloads will be unpacked and transferred to the custody of NASA.

The recovery ship has secured the Dragon spacecraft and the capsule's secondary systems are being powered down, according to Elon Musk. The cargo looks to be in good shape.

Since launching from Cape Canaveral on March 1, the Dragon flight lasted 25 days, 1 hour and 24 minutes. That is the longest Dragon mission to date.

Splashdown confirmed! The Dragon spacecraft has returned to Earth with nearly 2,700 pounds of space station cargo, punctuating its second operational flight to the complex. Splashdown occurred at 12:34 p.m. EDT (9:34 a.m. PDT; 1634 GMT), according to SpaceX.

The three main chutes are designed to slow the Dragon spacecraft to a splashdown velocity of just 11 mph.

"Recovery ship just heard the sonic booms from Dragon reentry and has data transmission lock," Elon Musk posted on his Twitter account.

SpaceX reports all three 116-foot-diameter main parachutes have deployed, and the recovery team near the splashdown zone 200 miles west of Baja California have a visual sighting of the descending spacecraft.

Two drogue parachutes have deployed from the Dragon spacecraft, according to SpaceX.

After deploying two drogue parachutes for stability, Dragon should now be descending through 10,000 feet under three 116-foot main parachutes, which are designed to slow the craft's speed to a gentle 11 mph at the time of splashdown.

There are no updates from SpaceX yet confirming a good parachute deployment.

SpaceX's founder and CEO Elon Musk just tweeted: "Dragon deorbit burn was good. All thrusters operating. On target for splashdown."

Temperatures outside the Dragon spacecraft are expected to reach up to 3,000 degrees Fahrenheit during re-entry.

Dragon should now be encountering the upper reaches of the atmosphere - a point known as entry interface - over the Pacific Ocean. Officials expect a communications blackout in the next few minutes, followed by deployment of the capsule's parachutes beginning at 12:25 p.m. EDT (1625 GMT).

30 minutes until splashdown. Dragon's blunt end is covered with Phenolic Impregnated Carbon Ablator, or PICA, a tough thermal protection system designed to withstand a high-speed, fiery atmospheric entry for missions returning to Earth from locations in deep space, such as asteroids, the moon, or Mars.

NASA's Stardust capsule, which returned dust from a comet, used PICA for a heat shield. And the Mars Science Laboratory Curiosity rover used a PICA heat shield during its landing at the red planet in August.

Dragon uses a formula known as PICA-X, which SpaceX says is an improvement over the formula used on Stardust.

SpaceX says the Dragon's trunk section has separated. The unpressurized component of the spacecraft will burn up on re-entry while the pressurized cabin braves the heat and deploys parachutes for a gentle splashdown in the Pacific Ocean.

The deorbit burn is now complete, according to SpaceX. Jettison of the 12-foot-diameter trunk section with its solar arrays should be occurring about now, but we don't have an update on that event.

SpaceX confirms the deorbit burn began on time.

Flying high above the Indian Ocean, the Dragon spacecraft is now firing its Draco thrusters for the deorbit burn, committing the capsule for return to Earth. The burn is expected to last 9 minutes and 59 seconds, according to SpaceX.

Dragon is carrying more than nearly 2,700 pounds of cargo from the space station in its pressurized cabin. The capsule is the only robotic cargo freighter able to retrieve equipment from the space station and return it to Earth for analysis or repairs.

A SpaceX spokesperson confirms the GNC bay door closed as planned this morning, and the deorbit burn is due to begin in about 10 minutes. Closure of the door is required for re-entry.

Two boats are in position near the Dragon splashdown zone. One of the vessels, the 100-foot American Islander, carries a crane to pluck the floating capsule from the Pacific Ocean, while another ship will serve as a tracking station to receive telemetry from the Dragon spacecraft.

About a dozen SpaceX engineers and technicians are at the splashdown site, which lies about 200 miles west of Baja California southwest of San Diego.

The SpaceX crew includes a four-person dive team to help retrieve the capsule after splashdown.

"Sad to see the Dragon go," said astronaut Tom Marshburn aboard the space station. "She performed her job beautifully [and is] heading back to her lair. Wish her all the best for the splashdown today."

Coming up at 10:25 a.m. EDT (1425 GMT), the Dragon spacecraft will close the door to its guidance, navigation and control bay.

Ignition of the capsule's thrusters is set for 11:42:33 a.m. EDT (1542:33 GMT) for an appoximately 10-minute deorbit burn. Splashdown more than 200 miles west of Baja California is scheduled for 12:34:56 p.m. EDT (1634:56 GMT).

NASA Television coverage of the Dragon resupply flight has ended. No live video is expected of the Dragon's splashdown, but you can check back here for updates on the status of the mission.

You can also follow our Twitter feed to get periodic updates.

See our Facebook page for quick images of today's departure from the space station!

Dragon's third and final departure burn is complete, moving the craft beyond the 200-meter keep-out sphere, an imaginary bubble around the space station.

Range between Dragon and the space station is now about 100 meters, or 328 feet.

The Dragon spacecraft has finished its second departure burn. A yaw maneuver is coming up at 7:05 a.m. EDT (1105 GMT), then a final departure maneuver is planned one minute later.

The first departure burn is complete. The space station crew reports it looks "both beautiful and nominal."

The first departure burn is complete. The space station crew reports it looks "both beautiful and nominal."

Astronaut Tom Marshburn has backed the robotic arm away to a distance of about 4 feet. The first of three rocket burns to guide Dragon away from the space station is coming up soon.

Dragon is now flying on its own, having been released from the grasp of the space station robotic arm at 6:56 a.m. EDT (1056 GMT) as the craft fly 252 miles high south of Australia.

SpaceX and NASA are both "go" for release of Dragon on time.

Five minutes until release of Dragon.

NASA and SpaceX report they are in good shape for the departure of Dragon with 2,668 pounds of cargo for the return trip to Earth.

The spacecraft are flying over the southern Indian Ocean right now.

Space station mission control in Houston is "go" for release of Dragon.

The Dragon spacecraft has been placed into free drift, a mode in which its Draco maneuvering thrusters are inhibited. This is a planned step required before release of the cargo craft.

Grasped by the robotic arm, the Dragon spacecraft is near its planned release point below the space station.

Astronaut Tom Marshburn will command the arm to release the capsule at 6:56 a.m. EDT (1056 GMT), while space station commander Chris Hadfield will man a communications panel to issue commands to Dragon if necessary.

The crew will monitor the spacecraft until it exits the so-called keep-out sphere 200 meters around the space station.

The robot arm is moving the Dragon spacecraft at a glacial pace in a choreographed series of translations commanded by the ground.

You can follow a timeline of the Dragon's departure and re-entry.

The robot arm maneuver to pull the Dragon spacecraft away from the space station's berthing port is being commanded by controllers on the ground in Houston. Astronauts Chris Hadfield and Tom Marshburn will take over control of the arm when it is time to release the spacecraft.

The Dragon spacecraft has been unberthed from the International Space Station's Harmony module. The vehicle was attached to the space station for nearly 23 days.

NASA reports the 16 bolts holding the Dragon spacecraft to the space station's Harmony module have been driven open, and the 58-foot robot arm will soon pull the commercial spaceship away from its mooring at the complex.

Dragon's strobe lights have been activated, and everything is progressing as planned this morning.

SpaceX's commercially-developed Dragon spacecraft is due to depart the International Space Station on Tuesday and begin its descent to Earth a few hours later.

The Dragon capsule is packed with 2,668 pounds of cargo, mostly exeriment samples and hardware from the space station's utilization payloads, life support and electrical systems, and crew medical equipment.

The spacecraft's pressurized section, about the size of a large walk-in closet, is also filled with crew supplies and cargo for the space station's international partners.

Astronauts finished transferring payloads into the Dragon spacecraft Tuesday and closed the capsule's hatch, according to NASA.

Departure activities will begin Tuesday at 4:05 a.m. EDT (0805 GMT) with the unlatching of the 12-foot-diameter Dragon spacecraft from the space station's Harmony module.

The lab's robotic arm will maneuver the craft to a release point about 30 feet below the space station, then let go at 6:56 a.m. EDT (1056 GMT). One minute later, the Dragon will begin the first of three rocket firings to fly away from the space station.

Later Tuesday, SpaceX will command the capsule to lower its orbit and close the door to Dragon's guidance, navigation and control bay, which contains the craft's grapple fixture and rendezvous sensors. The closure of the GNC bay door is a crucial event required before re-entry.

At approximately 11:42 a.m. EDT (1542 GMT), the spacecraft's Draco thrusters will ignite for about a 10-minute deorbit burn, slowing the capsule's velocity enough for it to drop out of orbit.

Moments after the conclusion of the deorbit burn, Dragon will jettison its trunk section, which is a mounting point for the craft's power-generating solar panels and ferried unpressurized supplies to the space station. The separation of the trunk leaves the battery-powered pressurized compartment of Dragon spacecraft alone for re-entry.

The gumdrop-shaped capsule will streak into Earth's atmosphere over the Pacific Ocean, encountering temperatures up to 3,000 degrees Fahrenheit. Dragon's carbon ablator heat shield, known as PICA-X, will protect the craft's skin from the intense heat of re-entry.

Falling through the stratosphere, Dragon will release two drogue parachutes at an altitude of about 45,000 feet for stability. The capsule's three 116-foot-diameter main parachutes will deploy about 10,000 feet above the sea, slowing the craft's descent to less than 15 mph.

Splashdown is scheduled for 12:34 p.m. EDT (1634 GMT) at a point in the Pacific Ocean 246 miles west of Baja California.

A 100-foot boat named American Islander will be stationed near the splashdown zone with a team of SpaceX engineers to recover the capsule. It will sail to the Port of Los Angeles, where it is scheduled to arrive as soon as late Wednesday, when SpaceX will hand over several critical science payloads to NASA for return to the Johnson Space Center in Houston.

SpaceX will transport the capsule to the company's rocket development facility in McGregor, Texas, for unloading of the rest of the spacecraft's cargo.

The Dragon spacecraft arrived at the space station March 3, two days after launching on a Falcon 9 rocket from Cape Canaveral, Fla.

NASA and SpaceX have delayed the departure of the Dragon cargo craft from the International Space Station from Monday until Tuesday, officials said Friday.

The one-day slip was ordered to avoid bad weather and rough seas in the Dragon's splashdown zone in the Pacific Ocean southwest of Los Angeles, according to NASA.

The additional day spent attached to the space station will not affect science samples scheduled to return aboard the spacecraft, NASA said in an update posted on its website.

The duration of the Dragon capsule's stay at the space station was driven by scientific requirements for samples launched and set to return on the privately-developed spacecraft.

NASA Television coverage of the gumdrop-shaped capsule's departure begins at 4 a.m. EDT (0800 GMT) Tuesday. Removal of the Dragon from the space station's Harmony module with the lab's robotic arm is set for 4:05 a.m. EDT (0805 GMT).

The robotic arm, under the control of NASA flight engineer Tom Marshburn, will release the Dragon capsule at 7:06 a.m. EDT (1106 GMT). SpaceX will command the spacecraft to execute a series of engine burns taking it away from the space station.

The deorbit burn using Dragon's Draco rocket thrusters is set to begin at 11:40 a.m. EDT (1540 GMT), and the capsule will jettison its trunk section and solar arrays before plunging back into Earth's atmosphere.

Using its thrusters to aim for a point in the Pacific Ocean 246 miles west of Baja California, the Dragon spacecraft will fall through the atmosphere protected by a specialized carbon heat shield before deploying parachutes and splashing down at 12:36 p.m. EDT (1636 GMT).

Ships positioned near the splashdown zone will pull the capsule from the sea and sail for the Port of Los Angeles, where SpaceX will begin handing over science samples to NASA.

Engineers on the ground guided the International Space Station's robot arm through a carefully-choreographed maneuver Wednesday extracting two grapple bars from the Dragon spacecraft's external cargo trunk.

The robot arm removed the equipment from the Dragon's trunk at about 3 p.m. EST (2000 GMT) and mounted the cargo on a temporary spot on the space station's truss several hours later.

Bolted together for launch, the grapple bars were built by Boeing and installed in the Dragon's trunk by SpaceX engineers. The 602-pound apparatus includes two grapple bars and bundling equipment holding the bars together.

Read our full story.

The robot arm is now pulling the 602-pound grapple bar apparatus from the Dragon spacecraft's trunk. The arm is moving slowly under the control of engineers on the ground.

Engineers are guiding the International Space Station's robotic arm through a remote-control procedure Wednesday to extract two grapple bars from the Dragon spacecraft's external cargo hold.

The slow-motion process is due to begin at about 2 p.m. EST (1900 GMT) and could last up to six hours, according to a NASA spokesperson.

It is the first time SpaceX's Dragon cargo craft has delivered hardware to the space station in its unpressurized trunk, which sits aft of the capsule's pressurized compartment.

The grapples bars were built by Boeing Co. and their support equipment was supplied by SpaceX. The equipment could be used to replace cooling radiators on the space station if necessary.

The 602-pound apparatus includes two grapple bars and bundles holding the bars together.

The robotic arm will move the grapples bars to a temporary location on the mobile transporter on the space station's truss backbone. During a spacewalk later this year, astronauts will move one grapple bar to each side of the truss, positioning them near the space station's deployable folding radiators.

Check out an animation of the robotic arm's extraction of the grapple bars.

The grapple bars are the first external payloads carried to the space station on SpaceX's commercially-developed Dragon spacecraft. Future Dragon flights could deliver experiments and spare parts for mounting outside the complex.

After the space shuttle's retirement, the Dragon spacecraft and Japan's HTV cargo freighter are the only two vehicles capable of delivering external supplies to the space station.

Canadian astronaut Chris Hadfield is tweeting daily from the International Space Station, and he posted several photos of the Dragon spacecraft's arrival Sunday on Twitter.

Check out some of his photos.

The hatch of the Dragon spacecraft was opened by the astronauts at 1:14 p.m. EST, allowing the crew to enter the pressurized capsule. Unpacking of Dragon's cargo is due to begin Monday.

Astronaut Chris Hadfield (@Cmdr_Hadfield) tweeted: "What a day! Reached & grabbed a Dragon, berthed her to Station & opened the hatch to find fresh fruit, notes from friends, and peanut butter."

SpaceX's Dragon spacecraft, packed with 2,300 pounds of supplies, approached the International Space Station on Sunday, holding steady a few feet below 450-ton complex as astronaut Kevin Ford carefully snagged the capsule with a robotic arm.

Ford plucked the commercial resupply ship from space at 5:31 a.m. EST (1031 GMT) as the space station flew 253 miles over northern Ukraine.

The astronauts handed over control of the lab's 58-foot robotic arm, nicknamed Canadarm 2, for engineers in Houston and Canada to maneuver the Dragon spacecraft into position on the Earth-facing port of the space station's Harmony module.

Read our full story.

All 16 bolts in the common berthing mechanism have driven to create a firm connection between Dragon and the Harmony module. The commercial spacecraft is now part of the International Space Station.

Final berthing occurred at 8:56 a.m. EST (1356 GMT) as the space station flew about 253 miles over the Arabian Sea.

First-stage capture is complete, and 16 bolts will soon drive to firmly attach Dragon to the space station.

The robot arm has positioned Dragon in the so-called ready-to-latch position at the Harmony module's Earth-facing berthing port. Four latches will close to create an initial connection.

After waiting for good communications, the robot arm operator has positioned Dragon about 2 feet from its berthing port on the Harmony module.

The robot arm has aligned the Dragon spacecraft with its berthing location on the Harmony module, and activities continue to run ahead of schedule.

Under remote control from the ground, the space station robotic arm is now in motion maneuvering Dragon toward the Harmony module's Earth-facing berthing port.

"Nice to see Canadarm 2 moving Dragon into alignment for berthing," said Canadian astronaut Chris Hadfield on the space station. "Looks great!"

Canadian astronaut Chris Hadfield is now activating the berthing mechanism on the Harmony module as robot arm engineers Houston and in Saint-Hubert, Quebec, prepare for a remote control installation of the Dragon capsule on the space station.

Coming up next: Ground controllers in Canada will take control of the robot arm to align the Dragon spacecraft with the Earth-facing berthing port on the Harmony module.

This will mark the first time a visiting vehicle such as Dragon has been installed under control of the ground.

"What a fantastic day," Kevin Ford radioed to mission control. "The vehicle's beautiful, the station's beautiful, the Canadarm 2 is beautiful, too, and it flew fantastic." "The prettiest thing of all was the dance between all of us just watching it come up the R-bar and come up to the perfect position was jsut amazing."

"Let me just say congratulations to the SpaceX and Dragon team in Houston and in California," said space station commander Kevin Ford.

"As they say, it's not where you start but where you finish that counts. You guys really finished this one on the mark. You're aboard, and we've got lots of science on there to bring aboard and get done, so congratulations to all of you."

Capture occurred 1 day, 19 hours and 22 minutes after the spaceship blasted off from Cape Canaveral on Friday.

Capture confirmed! The space station's robot arm has a firm grasp on Dragon as the two spacecraft fly 253 miles over northern Ukraine.

Ford is moving the robot arm toward Dragon now.

Mission control just radioed the crew they are "go" to capture Dragon.

Dragon has arrived at the capture point 10 meters, or 32 feet, beneath the space station and within the reach of the 58-foot robotic arm, which will be operated by commander Kevin Ford.

Now flying over the Atlantic Ocean, Dragon and space station are 18 meters, or 59 feet, apart as the commercial vehicle moves to a capture point about 30 feet from the complex.

Range is now 25 meters, or 82 feet, with a closure rate of about an inch per second.

With the space station crew, Houston and Hawthorne all ready for final approach, Dragon has resumed its glacial flight toward the complex to the so-called capture box, which is about 10 meters, or 32 feet, beneath the outpost.

Astronauts Kevin Ford and Tom Marshburn are following the rendezvous in the station's cupola.

The crew aboard the space station reports they are ready for Dragon to continue its approach. The flight director in Houston is polling the space station team for a "go" to proceed.

The Dragon spacecraft has arrived at a hold point 30 meters, or 98 feet, below the space station. There will be polls of teams in Houston and Hawthorne in the next few minutes before departing this hold point.

Dragon and the International Space Station have passed into orbital daylight as they approach the west coast of South America. Range is now about 45 meters, or 147 feet.

Range is now 80 meters, or 262 feet, and closing at about 3 inches per second.

Dragon has passed inside 100 meters, or 328 feet, beneath the space station as the two spacecraft pass through darkness over the South Pacific Ocean.

Mission control says grapple could occur before 6 a.m. EST (1100 GMT).

Dragon is now within 200 meters, or 656 feet, of the space station. Inside this range, the space station's crew has authority to issue an abort command if Dragon drifts out of its predefined approach corridor.

Dragon has resumed its approach to another hold point at 30 meters, or 98 feet.

Mission control is "go" for Dragon to continue its approach inside the keep-out sphere, an imaginary circle around the complex used for safety purposes.

Astronaut Tom Marshburn reports Dragon is in the expected position for this point in the rendezvous. The crew has a control panel linked with Dragon via UHF radio to issue simple commands in case of any problem. For example, the astronauts could tell the spacecraft to hold, abort or retreat.

Dragon has arrived at the 250-meter, or 820-foot, hold point. Teams in Houston and at SpaceX's headquarters in Hawthorne, Calif., will check to verify all is ready to continue on closer to space station.

Dragon's autonomous approach is guided with inputs from a LIDAR laser sensor and two thermal imagers.

The thermal and laser sensors independently measure the distance between Dragon and the space station to feed into the craft's guidance system.

Dragon's LIDAR sensor works by bouncing laser signals off the space station, creating a 3D map of the complex and giving Dragon's computer data on the craft's distance, closure rate, and orientation.

After the yaw maneuver, the Dragon spacecraft is flying closer to the space station along the R-bar, the imaginary line drawn between the space station and the center of the Earth.

The next hold point will be 250 meters, or 820 feet, beneath the complex. Dragon should stop there for about 10 minutes, then press on.

The station astronauts are working inside the station's windowed cupola, giving them an expansive view outside the complex.

The Dragon spacecraft has arrived at its hold point 350 meters, or 1,148 feet, directly below the space station. Next up is a short 180-degree yaw maneuver to align itself for final approach.

The space station is also reported to be in the correct attitude for Dragon arrival.

Check out a manifest of what's on-board Dragon about to be delivered to the space station.

Astronaut Chris Hadfield (@Cmdr_Hadfield) is tweeting: "Just caught sight of the Dragon spaceship, crisply white against the horizon, sneaking up on us from behind. We're readying to grapple."

Dragon continues to approach the space station ahead of schedule, according to mission control. Range is now about 1,000 meters, or about 3,280 feet.

Mission control in Houston has instructed the crew to begin monitoring Dragon's progress. Commander Kevin Ford, assisted by flight engineer Tom Marshburn, will operate the space station's robotic arm for the grapple procedure.

Ford, Marshburn and Canadian astronaut Chris Hadfield will monitor the approach via a two-day UHF data link with the Dragon spacecraft, which was established earlier this morning as the capsule flew in range of the station. The astronauts can issue simple commands to the Dragon capsule, such as abort or hold, in the event of an error or emergency during the last phase of the rendezvous.

The Dragon will initially rely on relative GPS navigation data to guide its approach to the space station. Once directly beneath the complex, its computers will switch to laser and thermal sensors.

Dragon carries a laser guidance sensor package and two thermal cameras to aid its final rendezvous with the space station.

The spacecraft will pause at 250 meters, or 820 feet, below the space station, then again at distances of 30 meters and 10 meters, or 98 feet and 32 feet.

At the 10-meter hold point, the craft will be grappled.

The laser sensor provides range, closing rate and attitude information on the station as Dragon autonomously flies near the space station.

Once grappled with the arm, the spacecraft will be maneuvered to its berthing port on the space station around 8:40 a.m. EST (1340 GMT).

Hadfield will oversee the common berthing mechanism on the Earth-facing port of the station's Harmony module, which will be Dragon's destination for its 22-day stay at the outpost.

Mission control in Houston reports the Dragon spacecraft is about 3.7 miles behind and less than a mile below the space station. Astronaut Kevin Ford says the crew has spotted the approaching spacecraft.

NASA told the space station crew that Dragon is running ahead of schedule, and it could be in position for grapple as soon as 6 a.m. EST (1100 GMT).

Canadian astronaut Chris Hadfield, now serving as flight engineer on the space station, tweeted this earlier today:

"Good Morning, Earth! Time to catch a Dragon. We'll grab it with Canadarm2 in about 5 hours, then go into its belly & see what it brought us."

The scheduled grapple time for Dragon has been adjusted to 6:31 a.m. EST (1131 GMT). Berthing operations are due to begin at about 8:40 a.m. EST (1340 GMT).

NASA has approved plans for SpaceX's Dragon spacecraft to rendezvous with the International Space Station on Sunday.

"The station's Mission Management Team unanimously agreed that Dragon's propulsion system is operating normally along with its other systems and ready to support the rendezvous two days after Friday's launch on a Falcon 9 rocket from the Cape Canaveral Air Force Station, Fla.," NASA said in an update posted on its website.

After a series of rendezvous burns to fine-tune its approach, Dragon will arrive at a point directly beneath the space station early Sunday. Once the capsule is about 30 feet below the complex, station commander Kevin Ford will use the lab's robotic arm to grapple Dragon at 6:01 a.m. EST (1101 GMT).

Dragon missed its opportunity to rendezvous as planned Saturday after problems with the craft's thruster system arose shortly after launch Friday.

Three of the capsule's four pods of thrusters did not pressurize as programmed after launch, leaving Dragon with only one set of functioning thrusters for the first few hours of the mission. The glitch meant the spacecraft could not conduct burns planned to initiate its approach to the space station.

Engineers brought the full complement of thrusters online Friday afternoon.

"SpaceX said it has high confidence there will be no repeat of the thruster problem during rendezvous, including its capability to perform an abort, should that be required," NASA said in the online update.

Mission control in Houston informed the space station crew of the news moments ago. "We're really looking forward to it," Ford said. "We've been getting good news all day that it was heading that way, and we can't wait to see it arrive."

SpaceX's robotic Dragon resupply freighter appeared to overcome a "frightening" propulsion glitch shortly after successfully launching from Cape Canaveral on Friday, giving managers hope the $133 million mission can keep its charge of delivering more than a ton of cargo to the International Space Station.

Controllers noticed a problem in the Dragon spacecraft's propulsion system moments after the capsule deployed from its Falcon 9 booster. Computers automatically put the capsule in a safe mode and stopped the craft from extending its power-generating solar arrays.

The trouble sparked a scramble to respond, diagnose and recover from the setback, which threatened to end the mission the same day it began.

Read our full story.

NASA doesn't expect a decision on a possible Dragon berthing date with the space station until tomorrow, but Sunday is a viable option.

Engineers will spend the evening evaluating data from Dragon's propulsion system.

"Thruster pods one through four are now operating nominally. Preparing to raise orbit. All systems green," Elon Musk just tweeted.

Dragon's four pods of Draco thrusters include sets of four and five jets. Three of the pods are required to approach the space station.

Controllers want to raise the craft's orbital perigee, or low point, as soon as possible because atmospheric drag could prompt a re-entry within a day or two at such low altitudes, according to Musk.

Dragon was deployed in an orbit stretching from a low point of 123 miles to a high point of 199 miles.

SpaceX founder and CEO Elon Musk just tweeted: "Pods 1 and 4 now online and thrusters engaged. Dragon transitioned from free drift to active control. Yes!!"

Dragon's rendezvous with the space station will not be tomorrow, mission control just told the lab's commander.

"They are making progress recovering their prop system, but it's not going to be in time to support the rendezvous and capture for tomorrow," NASA's spacecraft communicator told the crew. "So that is not going to happen tomorrow."

"OK, copy, sounds like another off-duty day for us," replied space station commander Kevin Ford. "We don't wish that. We wish it gets fixed and gets up here to us. That's really awesome they're working their way through the problems. That's what it's all about."

SpaceX hopes they can recover the faulty thruster system in time to support another rendezvous attempt in the next few days.

Mission control just radioed the space station crew an update on the Dragon status.

NASA's spacecraft communicator in Houston said SpaceX is still working through issues in the Dragon's propulsion system, and the mission's first rendezvous burn was delayed at least one orbit to about 2 p.m. EST (1900 GMT).

"If completed and if the propulsion system can be confirmed operationally functional, the grapple time tomorrow will not be affected," mission control told the crew.

Space station commander Kevin Ford responded: "That's space exploration for you. We sometimes have problems and work through them, and that's how you learn."

"If not tomorrow, maybe a couple of days down the road we'll get it licked."

A NASA official says three Dragon thruster pods are required to approach the International Space Station.

The Dragon spacecraft's Draco thrusters are mounted on four pods. Two of the pods contain five thrusters and the other two contain four thrusters.

According to SpaceX, the pods are positioned to provide complete control of the spacecraft's direction of motion (X, Y and Z axis), as well as orientation (roll, pitch and yaw).

SpaceX has released the following statement:

"Falcon 9 lifted off as planned and experienced a nominal flight. After Dragon achieved orbit, the spacecraft experienced an issue with a propellant valve. One thruster pod is running. We are trying to bring up the remaining three. We did go ahead and get the solar arrays deployed. Once we get at least 2 pods running, we will begin a series of burns to get to station."

Engineers are working to bring up the two other Dragon thruster pods (Nos. 2 and 4).

Dragon has extended its power-generating solar panels.

"Thruster pod 3 tank pressure trending positive. Preparing to deploy solar arrays," Musk just tweeted.

At least two thruster pods are needed to deploy the power-generating solar arrays, which stretch 54 feet tip-to-tip.

SpaceX says one thruster pod is working, and two are "preferred" to deploy solar arrays. Four thruster pods are on the Dragon spacecraft.

"We are working to bring up the other two in order to plan the next series of burns to get to station," a SpaceX spokesperson says.

NASA spokesperson Pat Ryan says flight controllers in Houston and at SpaceX's headquarters in California are studying whether they may need to change the sequence of rendezvous burns to approach the space station.

"It is a possibility that part of the response to the issue may be a rearrangement of the planned burn sequences for the Dragon spacecraft," Ryan said in a televised update from mission control in Houston.

Meanwhile, Elon Musk is tweeting updates on the situation. His latest update: "About to pass over Australia ground station and command inhibit override."

Musk is referring to an attempt to recover at least one of the three disabled thruster pods.

Dragon uses 18 Draco rocket jets to control its orientation and change its orbit to approach the space station.

"Holding on solar array deployment until at least two thruster pods are active," Musk just tweeted.

SpaceX founder and CEO just tweeted: "Issue with Dragon thruster pods. System inhibiting three of four from initializing. About to command inhibit override."

Solar array deployment was delayed while engineers attempt to regain attitude control of Dragon.

SpaceX founder and CEO just tweeted: "Issue with Dragon thruster pods. System inhibiting three of four from initializing. About to command inhibit override."

Solar array deployment was delayed while engineers attempt to regain attitude control of Dragon.

"It appears that although it achieved Earth orbit, Dragon is experiencing some kind problem right now," said John Insprucker, SpaceX's Falcon 9 product manager. We'll have to learn about the nature of what happened. According to procedure, we expect a press conference to be held a few hours from now. At that time, further info may be available."

ANOMALY. SpaceX is reporting some type of anomaly on the Dragon spacecraft. Deployment of the solar arrays was supposed to occur at T+plus 11 minutes, 45 seconds, but on-board cameras did not show the panels unfurl as planned.

SpaceX's webcast cut away from the solar array view and went to a slate.

T+plus 10 minutes, 10 seconds. Dragon has separated from the Falcon 9 upper stage.

T+plus 9 minutes, 40 seconds. Falcon 9 has reached orbit! Perigee is 199 kilometers and apogee is 323 kilometers. Orbital inclination is 51.66 degrees

T+plus 8 minutes. About one minute until the second stage Merlin engine is supposed to shut down as the vehicle reaches orbit. The rocket is aiming for an orbit with a low point of 124 miles, a high point of 202 miles, and an inclination of 51.6 degrees.

T+plus 7 minutes, 40 seconds. Falcon 9 is now traveling 1,000 kilometers northeast of Cape Canaveral at an altitude of 210 kilometers, a velocity of 5.6 kilometers per second, and a downrange distance of 1,080 kilometers.

T+plus 5 minutes. Everything reported to be going well with this second stage engine firing. The Merlin vacuum engine uses an ultra-thin niobium nozzle extension for greater efficiency in the upper atmosphere. The rocket's flight path is taking it northeast parallel to the U.S. East Coast.

T+plus 4 minutes, 30 seconds. SpaceX reports the Merlin vacuum engine is firing well. Altitude is 146 kilometers and velocity is 3.2 kilometers per second.

T+plus 3 minutes, 45 seconds. The Falcon 9 first stage engines have cut off, the stages have separated, and the rocket's second stage Merlin vacuum engine has ignited for its nearly six-minute firing to reach orbital velocity.

T+plus 3 minutes, 45 seconds. The Falcon 9 first stage engines have cut off, the stages have separated, and the rocket's second stage Merlin vacuum engine has ignited for its nearly six-minute firing to reach orbital velocity.

T+plus 2 minutes. Now soaring at an altitude of more than 20 miles, the Falcon 9 rocket's first stage will shut down and jettison in about one minute. Two engines will be turned off first, followed a few moments later by the remaining seven engines.

T+plus 1 minute. The Falcon 9 rocket is approaching the speed of sound and the phase of maximum aerodynamic pressure.

LIFTOFF of the Falcon 9 rocket carrying 2,300 pounds of cargo to the space station!

T-minus 60 seconds and counting. In the final minute of the countdown, the flight computer will command checks of the first stage Merlin engine steering system and the Falcon 9 propellant tanks will be pressurized for flight. Thousands of gallons of water from the ground facility's Niagara system will also be dumped onto the launch pad deck to suppress the sound and acoustics of liftoff.

The command to start the ignition sequence for the first stage will be issued at T-minus 3 seconds, triggering the Merlin engines' TEA-TEB ignitor source moments before the powerplants actually ramp up to full power.

T-minus 90 seconds and counting. The SpaceX launch director and the Air Force Eastern Range have given their final approvals for liftoff of the Falcon 9 rocket at 10:10:13 a.m. EDT (1510:13 GMT).

T-minus 3 minutes and counting. The rocket's destruct system is on internal power and being armed, the ground TEA-TEB first ignition system is ready for launch, and liquid oxygen topping is being terminated.

The second stage thrust vector steering system has checked out and is ready for flight.

T-minus 4 minutes, 30 seconds. Both stages of the Falcon 9 rocket are now running on internal power.

T-minus 5 minutes and counting. The Falcon 9 computer is aligned for flight. The automated sequence is now terminating loading of gaseous nitrogen into the second stage attitude control system.

T-minus 6 minutes and counting. The Falcon 9 computer and navigation system is configuring for flight and all nine Merlin engine pumps on the first stage are chilled in for ignition. The first stage fuel bleed sequence has started.

T-minus 7 minutes and counting. Within the next minute, the Falcon 9's flight computer will be commanded to its alignment state. The Merlin engine pumps are continuing to chill down.

T-minus 8 minutes and counting. The Dragon spacecraft is being placed on internal power.

T-minus 9 minutes and counting. Prevalves leading to the Falcon 9's Merlin first stage engines are opening, permitting super-cold liquid oxygen to flow into the engines to condition them for ignition.

T-minus 10 minutes and counting. The terminal countdown autosequence has started. Any hold after this point will result in an automatic abort.

T-minus 12 minutes. The launch team has verified all consoles are go for liftoff at 10:10 a.m. EDT (1510 GMT).

Engineers are watching a low temperature reading on a flight computer. The launch team is running warm gas into the compartment to help computer stay warm.

The Dragon team has finished an internal poll and is go for launch.

T-minus 17 minutes and counting. The Falcon 9 rocket stands 157 feet tall and measures 12 feet in diameter. At liftoff, its nine Merlin 1C first stage engines will generate about 855,000 pounds of thrust.

T-minus 20 minutes and counting. The final poll of the launch team will begin at T-minus 13 minutes before the countdown enters the final phase.

T-minus 25 minutes. All systems are in good shape for an on-time launch.

T-minus 35 minutes. At the time of launch, the International Space Station will be flying 253 miles over the Atlantic Ocean east of New England.

T-minus 37 minutes. All downrange tracking stations report they are ready to support today's launch, and winds aloft are acceptable for liftoff. Follow tonight's launch with this Facebook of major events.

T-minus 40 minutes. Countdown activities have resumed after a lull following fueling.

See our Facebook page for quick images of today's countdown to launch!

T-minus 55 minutes and counting. There continue to be no problems reported in the countdown. Launch weather office Mike McAleenan from the Air Force's 45th Weather Squadron just finished briefing the SpaceX team on the conditions around Cape Canaveral.

There is now a 90 percent chance of acceptable weather conditions at launch time.

Scattered mid-level clouds are passing over the launch complex, but they are not thick enough to be a concern for rocket-triggered lightning.

Temperature at launch time is expected to be 60 degrees Fahrenheit. A few clouds will be at 4,000 feet and scattered clouds are forecast at 14,000 feet, according to McAleenan.

All weather constraints are still observed "go" for launch.

All weather criteria are currently observed "go" for launch.

T-minus 1 hour, 30 minutes. All steps in the countdown up to this point, including fueling, C-band beacon tests, and checks of the Falcon 9's destruct system, should have been completed. The next event in the countdown comes at T-minus 40 minutes, when preps for liftoff will resume.

The strongback has been lowered to the launch position. All systems are go for launch at this point.

T-minus 1 hour, 49 minutes and counting. The strongback structure, a support structure that supports umbilical connections to the rocket, will soon be retracted about 15 degrees away from the Falcon 9.

The strongback is part of the Falcon 9's transporter-erector, a device which holds the rocket during rollout to the launch pad and erecting it vertical.

T-minus 2 hours and counting. Based on the latest trajectory of the International Space Station, the precise launch time will be 10:10:13 a.m. EST (1510:13 GMT).

Astronaut Tom Marshburn on the space station just tweeted: "1/2-way through our mission - awaiting the launch today of SpaceX's Dragon spaceship bringing food, experiments, and supplies!"

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T-minus 2 hours, 30 minutes. Fueling of the Falcon 9 rocket is underway at Cape Canaveral's Complex 40.

The liquid oxygen is stored in a 125,000-gallon sphere in the southeast quadrant of Complex 40. The rocket's RP-1 kerosene fuel is kept in cylinder-shaped tanks on the west side of the pad.

Engineers plan to load nearly 39,000 gallons of super cold liquid oxygen and almost 25,000 gallons of kerosene fuel into the first stage tanks. About 7,300 gallons of liquid oxygen and 4,600 gallons of kerosene will go into the second stage.

The propellants flow into the first stage through the launch mount at the base of the rocket. Kerosene and liquid oxygen will be pumped up the strongback umbilical tower to enter the second stage.

A few dozen engineers and managers are stationed inside the SpaceX Launch Control Center near the south gate to Cape Canaveral Air Force Station.

The Falcon 9 rocket is now standing vertical atop the launch pad at Complex 40.

The 157-foot-tall rocket has a near-instantaneous launch window to lift off at 10:10 a.m. EST (1510 GMT)

Workers at Complex 40 opened the doors of SpaceX's hangar and towed the Falcon 9 and its mobile transporter the 600-foot distance to the pad at about 8 a.m. EST Thursday.

Technicians loaded the final pieces of cargo into the Dragon capsule Thursday evening, using a specially-built housing to access the spacecraft's hatch while the rocket remained horizontal.

The slender 12-foot-diameter rocket was lifted atop the launch pad with hydraulic pistons a few minutes ago and was fully vertical by 1:20 a.m. EST (0620 GMT).

The two-stage booster is attached to a transporter-erector, a specially-built apparatus that doubles as a device to lift the rocket vertical and provide umbilical connections to the rocket during the countdown.

The strongback also provides structural support to the rocket from high winds and other weather.

Once in place at the launch pad, the transporter-erector was to be structurally mounted to the pad and plugged into communications, electrical, fueling and pressurization systems through a series of pins and flanges.

The flanges link the rocket with ground storage tanks containing liquid oxygen, kerosene fuel, helium, gaserous nitrogen and the first stage ignitor source called triethylaluminum-triethylborane, better known as TEA-TEB.

The Falcon 9 rocket is integrated with the transporter inside the SpaceX hangar, including attachments to the launcher's propellant plumbing and avionics systems.

Comparatively simple connections are made in the outdoors once the rocket is at the pad. It's part of the Falcon 9's streamlined processing infrastructure, which is designed to ultimately support transportation to the launch pad within a few hours before blastoff.

The weather outlook continues to show a 80 percent chance of acceptable conditions for launch, calling for scattered-to-broken clouds and brisk winds in the vicinity of the launch pad at Cape Canaveral Air Force Station, Fla. The only potential threats from weather are thick clouds and ground winds.

The SpaceX launch team will power up the Falcon 9 rocket and its Dragon payload after 3 a.m. EDT (0800 GMT).

Follow the countdown with this timeline of key milestones.

Exquisite analysis and extensive testing by SpaceX engineers, with support and advice from NASA experts, showed a dramatic engine failure on the company's last launch was caused by a material flaw in the engine's protective jacket, a SpaceX official said Thursday.

Managers are confident the same problem will not show up during Friday's launch of a Falcon 9 rocket, the first flight of the two-stage booster since the Oct. 7 launch which suffered the engine failure.

Read our full story.

The Falcon 9 rocket left its hangar and rolled to the launch pad this morning, where a few last-minute cargo items will be packed inside the Dragon capsule before liftoff tomorrow.

SpaceX will lift the Falcon 9 rocket vertical atop the launch pad tonight.

The weather forecast continues to look favorable, but the odds of good conditions have lessened slightly to an 80 percent of acceptable weather, according to Air Force meteorologists.

The main threats are gusty ground winds and potential thick clouds over Cape Canaveral. The outlook is similar for Saturday, again with an 80 percent chance of acceptable conditions.

"Winds will be occasionally gusty from the northwest during this period but are forecast to remain below liftoff limits," meteorologists wrote in a forecast summary. "Upper level energy is forecast to rotate into the Gulf of Mexico creating clouds across Florida that may be the triggered lightning threat height range.

"This forecast arrival time of this cloudy area has been inching earlier on each successive model run. It now looks like the cloud mass will arrive prior to the Friday's launch window and remains in the area to just after Saturday's launch window."

SpaceX and NASA officials will hold a prelaunch press conference at 3 p.m. EST (2000 GMT).

SpaceX managers today gave the green light to continue preparations to launch the company's Falcon 9 rocket Friday.

Top officials met for a Launch Readiness Review today to discuss the status of launch preparations and any unresolved issues before pressing ahead with final preflight steps, loading of experiment specimens and fresh food into the Dragon spacecraft, and the start of the countdown Friday morning.

Liftoff of the 157-foot-tall rocket remains scheduled for 10:10 a.m. EST (1510 GMT) from the SpaceX-run launch pad at Complex 40 at Cape Canaveral Air Force Station, Fla.

See a listing of backup launch opportunities over the weekend.

The weather forecast is favorable with 90 percent odds of acceptable conditions for launch Friday. The only concern is brisk ground winds potentially exceeding launch weather rules.

Air Force forecasters call for scattered low-level and mid-level clouds, northwest winds of 12 knots with gusts to 20 knots, and a launch time temperature of 60 degrees Fahrenheit.

NASA will deliver the mission's final cargo items to SpaceX on Thursday for installation into the Dragon capsule's pressurized cabin.

Engineers will then seal the craft's hatch and lift the Falcon 9 rocket atop the launch pad overnight, followed by the start of the countdown in the wee hours Friday morning.

The forecast for Friday calls for brisk weather, at least by Florida standards, but little chance weather conditions will prevent an on-time launch of SpaceX's Falcon 9 rocket.

There is just a 10 percent chance of weather violating preset rules for a Falcon 9 launch, according to U.S. Air Force forecasters. The prediction for Saturday calls for a 20 percent chance of violation.

"Progressively colder temperatures are expected to infiltrate Central Florida each day from Wednesday through the next several days," Air Force meteorologists wrote in a weather synopsis. "Winds will be gusty from the northwest during this same period but are forecast to remain below liftoff constraint level. On Saturday, upper level energy is forecast to rotate into the Gulf of Mexico creating clouds that may lower to levels that make them a triggered lightning threat."

Ground winds are the primary concern for Friday's launch, which has an instantaneous opportunity at 10:10 a.m. EST (1510 GMT). If launch is delayed until Saturday, winds and thick clouds are the worry.

The forecast calls for scattered stratocumulus clouds between 4,000 feet and 6,000 feet, a temperature of 60 degrees Fahrenheit, and winds out of the northwest at 12 knots with gusts to 20 knots.

SpaceX engineers hoisted a Falcon 9 rocket on the launch pad, filled the launcher with liquid propellant, and fired the booster's nine main engines Monday, crossing off a big item on the rocket's preflight checklist ahead of its planned launch Friday.

The Falcon 9 rocket's nine Merlin 1C engines ignited at 1:30 p.m. EST (1830 GMT), ramping up to more than 850,000 pounds of thrust and maintaining full power for about two seconds.

"During the static fire test today, SpaceX engineers ran through all countdown processes as though it were launch day," the company said in a statement. "All nine engines fired at full power for two seconds, while the Falcon 9 was held down to the pad. SpaceX will now conduct a thorough review of all data and continue preparations for Friday's targeted launch."

Read our full story.

It's been three hours since the Falcon 9 rocket ignited its engines for a prelaunch static fire test, but there's no word on how the test went or whether it achieved its goal of two seconds of full thrust.

The first stage's Merlin 1C engines were supposed to ignite for about 3.5 seconds. In the final minute of the countdown, vapors from the rocket's cryogenic propellant disappeared as the vehicle pressurized its tanks.

At 1:30 p.m. EST (1830 GMT), a flicker of orange flame appeared at the base of the rocket, and a stream of exhaust flowed from the flame trench at Complex 40. The exhaust appeared to flow for several seconds.

SpaceX typically issues a brief statement shortly after the conclusion of the test confirming it completed its objectives.

The Falcon 9 countdown reached zero at 1:30 p.m. EST, and the rocket's nine first stage engines briefly fired as a plume of steam erupted from the launch pad.

We're waiting on official word from SpaceX if the static fire was successful.

SpaceX's Falcon 9 rocket is standing on its launch pad at Cape Canaveral for a static fire hold-down engine firing today, a customary prelaunch test before each flight of the commercial booster.

Ignition of the rocket's nine Merlin engines is targeted for approximately 1:30 p.m. EST (1830 GMT) on Complex 40 at Cape Canaveral Air Force Station, Fla.

Engineers will fill propellant tanks in both stages of the 157-foot-tall Falcon 9 rocket this afternoon. The stages are powered by Merlin engines burning refined kerosene fuel and liquid oxygen.

The liquid oxygen is stored in a 125,000-gallon sphere in the southeast quadrant of Complex 40. The rocket's RP-1 kerosene fuel is kept in cylinder-shaped tanks on the west side of the pad.

Engineers plan to load nearly 39,000 gallons of super cold liquid oxygen and almost 25,000 gallons of kerosene fuel into the first stage tanks. About 7,300 gallons of liquid oxygen and around 4,600 gallons of kerosene will go into the second stage.

The propellants flow into the first stage through the launch mount at the base of the rocket. Kerosene and liquid oxygen will be pumped up the strongback umbilical tower to enter the second stage.

The Falcon 9 rocket's nine Merlin first stage engines will be ignited today for 3.5 seconds, enough time to verify systems on the ground and the launch vehicle responsible for the final few seconds of the countdown.

The engines will be at full power for approximately 2 seconds.

The engines will produce nearly 1 million pounds of total sea level thrust, more than four times the power of a 747 jumbo jet at full throttle. The engines consume about 3,200 pounds of kerosene and liquid oxygen propellants per second, according to SpaceX.

SpaceX engineers will spend the next week testing its next Falcon 9 rocket and packing its privately-built Dragon spaceship with supplies and experiments before the next commercial resupply flight to the International Space Station blasts off March 1.

Launch week begins Monday with the Falcon 9 rocket's customary preflight static fire test, in which the launcher's nine first stage engines ignite on the launch pad.

The static fire, scheduled for Monday afternoon at SpaceX's launch pad at Cape Canaveral, will occur at the end of a practice countdown. The launch team stationed about 10 miles from the rocket will load kerosene and liquid oxygen propellants into the booster and oversee a computer-controlled countdown sequence leading to ignition of the Falcon 9's first stage engines.

Read our full story.