NASA Launch Coverage

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GLAST Launch Blog
GLAST Launches On June 11, 2008, a Delta II rocket lifted off at 12:05 p.m. EDT from Cape Canaveral Air Force Station's Launch Pad 17-B, successfully carrying the GLAST spacecraft into space. Check the blog below to see how the countdown unfolded. All times are Eastern Daylight Time.

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1:30 p.m. - Thanks for joining us for the countdown and successful launch of the GLAST spacecraft. You can continue to follow the GLAST mission by checking the GLAST Web site at

It's a fact... GLAST's Large Area Telescope is a 3-ton detector with almost a million channels of electronics, but it uses less than half the power of an ordinary hair dryer.

1:20 p.m. - Telemetry from Kwajalein tracking station has confirmed that the GLAST spacecraft has separated from its second stage and has reached its circular orbit 350 miles above Earth.

1:15 p.m. - Confirmation from tracking that the second stage has completed the second burn.

It's a fact... At approximately 75 minutes after launch, the GLAST spacecraft will separate from the second stage as it reaches its circular orbit 350 miles above Earth.

12:42 p.m. - The spacecraft continues in coast phase.

It's a fact... The GLAST mission is a collaboration between NASA and the U.S. Department of Energy, along with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the U.S.

12:15 p.m. - We have confirmation of the second stage engine cutoff. This puts the vehicle into a coast phase that will last approximately 58 minutes. At that time, the second stage engine will fire for a second time while the spacecraft is about 300 nautical miles over the South Pacific.

12:10 p.m. - Main engine cutoff is confirmed. The second stage has separated from the first and fired its engine at about 69 nautical miles over the Atlantic Ocean. This burn will last for 5 minutes and 35 seconds, during which time the two halves of the payload fairing will be jettisoned, exposing the GLAST spacecraft.

12: 09 p.m. - The final three solid rocket boosters have burned out and jettisoned. We are waiting for main engine cutoff.

12:07 p.m. - The first six solid rocket boosters have burned out and jettisoned. The final three boosters have ignited, and will burn for about 76 seconds.

12:05 p.m. - ...three ...main engine start ...two ...and liftoff of GLAST's mission to explore the extreme universe! With the main engine and six of the solid rocket boosters burning, the Delta II is thundering through the sky.

12:03 p.m. - We're now at the T-2 minute mark and counting, as the liquid oxygen tank is raised to flight pressure. During the last minute before liftoff, the launch enable switch will be set to "on," the liquid oxygen fill and drain valve closed, and the vehicle ignition system will be armed. The main engine will start at the T-2.5 second mark.

12:01 p.m. - We are at T-4 minutes and counting as the Delta II rocket stands poised in the Florida mid-day sun, ready to propel GLAST toward space. The spacecraft is now on internal power.

11:56 a.m. - The team has given the "go" to come out of the hold at 12:01 p.m.

11:51 a.m. - The launch team is setting up for a new launch time of 12:05 p.m.

11:46 a.m. - The extended hold is due to a radar outage at Antigua tracking station. The radar there is back up and working. We are awaiting a new launch time.

11:41 a.m. - We are at T-4 minutes and still holding. The launch team has extended the hold. Stand by for a new launch time.

11:34 a.m. - The launch team has given a resounding "go" for launch. The countdown is due to pick up in about seven minutes.

11:31 a.m. - We have reached T-4 minutes and holding. In about three minutes, Launch Manger Omar Baez will poll his launch team before resuming the count.

11:25 a.m. - We're coming up on the planned 10-minute hold in the countdown. The clock will stop at T-4 minutes. During this hold, the launch manager will conduct the final readiness poll before the clock begins counting down the final minutes to liftoff. The rocket's fuel tank is being pressurized.

11:20 a.m. - The liquid oxygen tank will be continually topped off as a small amount of the oxygen is vented during the countdown to prevent pressure from building within the tank.

11:10 a.m. -The engine steering checks are under way. During these tests, the engine nozzles of both the first and second stages of the rocket are put through a series of programmed movements to verify their ability to steer the rocket as it climbs spaceward.

10:55 a.m. - Less than one hour left until the Delta II lights up the sky, sending the GLAST spacecraft toward its orbit around Earth. The spacecraft and rocket are both in good shape, and the Florida weather is cooperating.

10:48 a.m. - The filling of the liquid oxygen is now 96 percent complete.

It's a fact... When stowed inside the fairing atop the Delta II rocket, the spacecraft measures 9.2 feet high by 8.2 feet in diameter.

10:30 a.m. - The countdown continues to go smoothly as the loading of the liquid oxygen is under way. There are no technical concerns with either the spacecraft or the rocket, and weather continues to be 60 percent favorable. The only planned hold in today's count comes at the T-4 minute mark.

10:08 a.m. - NASA Launch Manager Omar Baez just conducted a poll of his launch team and they are "go" for loading of the super-cold liquid oxygen. As about 15,000 gallons of the propellant flow into the rocket's first stage, engine heaters help stabilize the vehicle.

The countdown clock is at T-87 minutes and counting down toward launch of the Delta II rocket carrying the GLAST spacecraft.

10:00 a.m. - We are at T-95 minutes and counting. The loading of the 10,085 gallons of RP-1 is complete.

The launch team just received a 60 percent favorable weather report from Launch Weather Officer Joel Tumbiolo. Today's weather pattern is expected to mirror yesterday's Space Coast weather. Showers and thunderstorms are expected to develop along the sea breeze front, but clouds to the west over Central Florida could actually delay the beginning of the unfavorable weather. At this time, weather at the 11:45 a.m. liftoff is expected to hold, but could deteriorate during the duration of the almost two-hour window.

9:50 a.m. - Earlier, the final countdown began when the T-150 minute hold was released. At that time, the Launch Complex 17 area was cleared of non-essential personnel so that fueling of the Delta II rocket could begin. The rocket's guidance system was turned on, the first stage and second stage pressurization began, and the launch team gave the "go" to load 10,085 gallons of RP-1, which began at 9:30 a.m.

The Delta II's first stage engine is powered by RP-1 -- a highly refined form of kerosene -- combined with liquid oxygen. Shortly, the launch team will give the nod to begin pumping in the liquid oxygen. This Delta II is also getting added lift by using nine strap-on solid rocket boosters for this launch.

As the vehicle's C-band radar transponder beacon check is conducted, the team is standing by for a weather briefing.

9:45 a.m. - Live from Cape Canaveral Air Force Station in Florida, good morning and welcome to our launch coverage of NASA's GLAST spacecraft. The two-stage Delta II rocket set to carry the spacecraft stands just a few miles away on Launch Pad 17-B, and the weather along Florida's space coast is sunny and hot. We'll be getting the official launch weather report shortly.

Liftoff is set for two hours from now at 11:45 a.m., and the team has a launch window that lasts until 1:40 p.m.

GLAST is short for Gamma-ray Large Area Space Telescope. This new intergalactic detective will study mysteries of the universe such as gamma-ray bursts, dark matter, black holes, neutron stars, supernova remnants and more. GLAST will be the first observatory of its kind to daily survey the entire sky using its highly sensitive instruments.

Stay right here as we count down to the launch of this exciting new mission to the universe.

Live Coverage Team
Blog Updates: Cheryl L. Mansfield
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Video Uploads/Images: Steve Siceloff
Video Production: Alysia Lee
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