4:15 GMT (11:15 p.m. EST): The last satellite, FalconSat 3, is released and the Atlas 5 mission is concluded after 65 minutes.

4:11 GMT (11:11 p.m. EST): CFESat is seperated.

4:04 GMT (11:04 p.m. EST): STPSat 1 is released from the Centaur.

3:58 GMT (10:58 p.m. EST): Last engine cutoff. After another coast phase, the last three satellites will be seperated from the Centaur upper stage.

3:56 GMT (10:56 p.m. EST): Third RL10 ignition for nearly 2 minutes. That will make it the longest total burn time of the Centaur upper stage ever on an Atlas 5 rocket.

3:45 GMT (10:45 p.m. EST): RL10 engine cutoff. Now there's a further coast phase until third and last engine ignition.

3:43 GMT (10:43 p.m. EST): Second RL10 ignition.

3:32 GMT (10:32 p.m. EST): MidSTAR-1 seperation. The Centaur will now orient for its next burn phase.

3:28 GMT (10:28 p.m. EST): The Orbital Express satellites are seperated and the Centaur is orientied for the MidSTAR-1 seperation.

3:24 GMT (10:24 p.m. EST): RL10 cutoff. The Centaur will now enter a coasting phase and first satellite seperation.

3:21 GMT (10:21 p.m. EST): The Centaur is some 6 minutes into its first burn, that will take 10 minutes. Everything is nominal.

3:15 GMT (10:15 p.m. EST): Payload fairing is jettisoned.

3:14 GMT (10:14 p.m. EST): First stage engine cutoff and upper stage ignition.

3:12 GMT (10:12 p.m. EST): Vehicle passed maximum dynamic pressure Max-Q

3:10 GMT (10:10 p.m. EST): Liftoff of the Atlas 5 STP-1 mission.

T-4 and counting 3:06 GMT (10:06 p.m. EST): Countdown resumed. All systems are set for launch.

3:04 GMT (10:04 p.m. EST): All systems including the range are go. Liftoff is now set to 3:10 GMT.

2:55 GMT (9:55 p.m. EST): All systems are go except for the range safety because of the radio frequency interference issue that is still being investigated.

2:48 GMT (9:48 p.m. EST): The hold is may be extended to 3:10 GMT.

2:45 GMT (9:45 p.m. EST): The interfering radio frequency has disappeared but the helicopters are still out in the safety zone.

2:43 GMT (9:43 p.m. EST): The hold is extended to 3:00 GMT (10 p.m. EST) due to the range problem. Helicopters are currently underway for the checking of the safety zone.

2:37 GMT (9:37 p.m. EST): A booster valve problem is solved. The range problem is a radio frequency interference that could lead to a problem with the flight termination system. That issue is under investigation.

2:27 GMT (9:27 p.m. EST): A problem is reported and the rocket is currently on no-go. The hold will be extended by five minutes.

T-4 and holding, 02:23 GMT (9:23 p.m. EST): The rocket is now in its pre-planned 10 minute hold at T-4.

01:50 GMT (8:50 p.m. EST): The first stage is nearly filled while the upper stage already is in the topping off mode. The launch is now 47 minutes away and the clock is counting.

01:17 GMT (8:17 p.m. EST): The Centaur stage's oxidizer tank is filled and the topping off process has started. The first stage is continued to be filled with the liquid oxygen and the chilling down of the hydrogen tank of the Centaur has started.

01:01 GMT (8:01 p.m. EST): Three tanks need to be filled tonight. The oxidizer tanks of the Centaur upper stage and the Atlas 5 core stage and the hydrogen fuel tank of the Centaur. The kerosene used by the RD-180 engine on the first stage was already tanked as this isn't a cryogenic propellant.
Tanking of cryogenic propellants always occurs in several phases. First, the tank and the pipes are chilled down for the supercold propellants. Then a slow tanking process begins in order to give the materials enough time to take the propellant's temperature. After that slow filling to about 10 to 20% of a stage, a fast fueling commences that fills a tank up to 80 to 90% of its capacity. Again a slow tanking takes place to full capacity.
The final phase that is continued until shortly before a launch is the topping off. The cryogenic fuels boil off at a quite high rate, especially in warm regions like Florida so they need to be replenished.

00:46 GMT (7:46 p.m. EST): The fueling process of the Centaur upper stage of the Atlas 5 rocket has begun with the filling of the liquid oxygen (LOX) tank.

The satellites that will fly on the STP-1 missions are:
The primary payload, Orbital Express (OE), weighing a total of 1,200 kilograms, will demonstrate the ability of a satellite to autonomously service other satellites including parts replacement and fueling. The OE consists of two satellites, the repair and service satellite called ASTRO (On-orbit Rendezvous, Docking, Fueling & Instrument Replacement) and the target satellite called NEXTSat (Next Generation Satellite).

The secondary payloads are four more satellites:
SPSSat-1, weighing about 170 kilograms, will analyse the middle atmosphere.
CFESat of the Los Alamos National Laboratory weighs about 120 kilograms and will test and demonstrate future satellite technologies like reconfigurable electronic curcuits.
MidSTAR-1, weighing 150 kilograms, provides services for educating officer candidates at the United States Naval Acadamy.
FalconSat-3 finally weighs 45 kilograms and provides educational services for officer candidates at the United States Air Force Acadamy.

19:10 GMT: A few hours before launch, the weather remains stable with a few clouds at 4,000 feet and slow winds under 10 km/h from the southeast. 

March 8, 2007: The Atlas 5 rocket, production number AV-013 is ready on launch pad 41 for its launch today carrying 6 satellites of the STP-1 mission of the US Air Force.

This Atlas launch will be the first Atlas 5 launch for the US Air Force as well as the first Atlas launch under the management of the United Launch Alliance ULA.

Liftoff is scheduled for 9:37 p.m. EST (2:37 GMT) promising a spectacular night launch.