9:30am ET Sunday Update: With more favorable weather than on Saturday, an Atlas V rocket made a smooth launch from Florida on Sunday morning at 9:14am ET (13:13 UTC). The booster sent an X-37B space plane into orbit for the US Space Force, where the uncrewed vehicle is likely to remain for a couple of years before returning to Earth.
7:15am ET Sunday Update: After Saturday’s scrub due to a poor weather, an Atlas V rocket is again being prepared for launch on Sunday morning. As of two hours before the launch window opens, weather conditions are go. And launch weather officer Jessica Williams predicts an 80-percent chance of acceptable conditions at the opening of the window, at 9:14am ET (13:14 UTC).
The webcast for the launch of the Space Force’s secretive space plane, embedded below, will open about 20 minutes before that time.
10:30am ET Update: Alas, the weather never did quite cooperate on Saturday. United Launch Alliance held on to the very end of the launch window, even counting down to T-1:40, but weather conditions remained in violation. The Atlas V rocket will now be recycled for another launch attempt on Sunday, at 9:14am ET (13:14 UTC). The forecast calls for improving weather by then.
8:30am ET Update: Due to poor weather at Cape Canaveral in Florida this morning, the launch time has been reset to 10:13am ET (14:13 UTC). The rocket remains fueled with liquid oxygen and kerosene and is ready to fly.
Original post: Engineers and technicians with United Launch Alliance were preparing an Atlas V rocket for launch on Saturday morning from Cape Canaveral Air Force Station in Florida.
The rocket has an approximately 150-minute launch window that opens at 8:24am ET (12:24 UTC). Before sunrise, the command was issued to begin loading the Atlas V rocket with cryogenic fuels for launch.
However, there were concerns about weather. On and off during the early morning hours, conditions at the launch range went into “red” for cumulus clouds, and ground-level winds were just above acceptable limits. Forecasters have estimated about a 40-percent chance of “go” conditions for a launch on Saturday. If this mission flies, a Falcon 9 rocket may launch just 20 hours later from the Cape, early on Sunday.
This mission will carry the X-37B space plane into orbit for the Space Force. There are two operational copies of this uncrewed vehicle, which were built by Boeing, measure 8.9 meters long, and resemble a miniature space shuttle orbiter. The fleet has previously launched four times on the Atlas V rocket and, most recently, once on SpaceX’s Falcon 9 rocket in September 2017. The X-37B has remained in orbit for as long as 779 days before returning to Earth. It lands on a runway at Kennedy Space Center in Florida.
“The ability to test new systems in space and return them to Earth is unique to the X-37B program and enables the US to more efficiently and effectively develop space capabilities necessary to maintain superiority in the space domain,” the Air Force said earlier this month.
US military officials have spoken a little more openly about this sixth flight of the secretive space plane in advance of its launch. According to the Air Force, this is the first time the X-37B will fly with a service module on the aft of the vehicle, which will allow for expanded research and experimentation. One of this mission’s experiments will attempt to transform solar radiation into radio-frequency microwave energy, with the intent of studying the potential for beaming solar power back to Earth. This vehicle will also release the FalconSat 8 spacecraft, which was developed by Air Force Academy cadets.
Assuming the weather allows for United Launch Alliance to press ahead with an attempt on Saturday, the company will begin a webcast about 20 minutes before liftoff.
Listing image by ULA