Update for 5:50 p.m. ET on Nov. 4: Today's planned NROL-101 launch has been scrubbed due to a problem with a ground-system valve. The next launch attempt could come on Friday (Nov. 6), ULA officials said.
CAPE CANAVERAL, Fla. — United Launch Alliance (ULA) is set to send an Atlas V rocket into space on Wednesday evening (Nov. 4), following a 24-hour delay to swap out hardware, and you can watch the action live.
The two-stage rocket will blast off from Space Launch Complex 41 here at Cape Canaveral Air Force Station in Florida, carrying with it a classified payload for the National Reconnaissance Office, which manages the U.S. government's fleet of spy satellites.
You can watch the launch live here and on the Space.com homepage, courtesy of ULA, beginning about 15 minutes before liftoff. You'll also be able to watch the launch directly from ULA.
Liftoff is set for just after sunset, at 5:54 p.m. EST (2254 GMT). If the weather and clouds cooperate, the launch could put on a dazzling display as twilight is the magic hour for rocket launches; at dawn and dusk, the sun is positioned in a way that can illuminate the rocket's plume and make it look like a giant jellyfish in the sky. These launches are often confused for UFOs because of the weird squiggly clouds produced. (Spoiler alert: It's definitely not aliens.)
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Forecasters at the 45th Weather Squadron have predicted a 70% chance of favorable launch conditions on Wednesday night. The main concern is ground winds, which are expected to come in from the northeast at 15 to 20 knots (17 to 23 mph or 28 to 37 kph), with gusts up to 26 knots (30 mph or 48 kph). In an official report issued on Tuesday night (Nov. 3), meteorologists said that they expected most clear skies and breezy winds. It's unclear when the backup date would be if the rocket cannot get off the ground Wednesday night, as SpaceX is scheduled to launch an upgraded GPS satellite on Thursday evening.
Designated NROL-101, the mission is ULA's fifth so far this year. The National Reconnaissance Office has been stingy with details about the payload, which is typical for these types of missions, but did confirm that the payload was designed and built by the NRO.
"NROL-101 supports NRO's overall national security mission to provide intelligence data to the United States' senior policy makers, the Intelligence Community and Department of Defense," the NRO wrote in a press kit for the mission.
Forecasters at the 45th Weather Squadron have predicted a 70% chance of favorable launch conditions on Wednesday night. The main concern is ground winds, which are expected to come in from the northeast at 15 to 20 knots (17 to 23 mph or 28 to 37 kph), with gusts up to 26 knots (30 mph or 48 kph). In an official report issued on Tuesday night (Nov. 3), meteorologists said that they expected most clear skies and breezy winds. It's unclear when the backup date would be if the rocket cannot get off the ground Wednesday night, as SpaceX is scheduled to launch an upgraded GPS satellite on Thursday evening.
Designated NROL-101, the mission is ULA's fifth so far this year. The National Reconnaissance Office has been stingy with details about the payload, which is typical for these types of missions, but did confirm that the payload was designed and built by the NRO.
"NROL-101 supports NRO's overall national security mission to provide intelligence data to the United States' senior policy makers, the Intelligence Community and Department of Defense," the NRO wrote in a press kit for the mission.
The flight will mark the 29th mission for the NRO and the 17th such mission launched on an Atlas V. Over the weekend, ULA officials conducted a launch readiness review giving the go-ahead for launch. Early Monday morning (Nov. 2), the rocket rolled out of its hangar and over to the launch pad at SLC-41, located just one-third of a mile (half a kilometer) away.
Shortly after the rocket arrived, crews noticed an issue with the vehicle's environmental control system. High winds may have damaged the line that feeds conditioned air to the rocket's payload, according to ULA officials. This issue requires a fix that cannot be done at the pad, so crews transported the vehicle back to its integration facility for repairs.
The work was completed late Tuesday night (Nov. 3), with ULA president and CEO, Tory Bruno, tweeting that the problematic duct was swapped out with a reinforced one. The rocket was then sent back to the pad to begin launch preparations.
After embarking on its 1,800-foot (550 meters) journey, the rocket was powered up and began a series of prelaunch checkouts that will lead to fuel loading, a task that will be initiated two hours before liftoff, and ultimately launch, if all goes as planned.
The mission will mark the 86th flight of an Atlas V since 2002, and the fifth to fly this year. It will also be ULA's 30th launch to carry an NRO payload. The agency, which manages the U.S. government's fleet of spy satellites, uses these eyes in the sky to provide optical and radar imagery, intercept communications from adversaries, as well as to send secured communications to intelligence agencies.
"ULA is proud to play a pivotal role in support of our mission partners and national security by keeping our country safe, one launch at a time," Gary Wentz, ULA vice president of government and commercial programs, said in a company email statement.
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The 206-foot-tall (63 m) Atlas V is fueled by a mix of liquid oxygen and RP-1, a refined form of kerosene used for spaceflight, and liquid hydrogen in its upper stage. The vehicle will fly in the "531" configuration, with three solid rocket motors, a 17.7-foot (5.4 m diameter) payload fairing.
Today's flight will mark the fourth time an Atlas V has flown in the 531 configuration, and the first mission to use newly upgraded solid rocket motors. The GEM 63 strap-on boosters are manufactured by Northrop Grumman and were made to replace the previous models made by Aerojet Rocketdyne. Each of the 66-foot-long (20 m) rocket motors packs an extra 373,800 pounds of thrust. According to ULA, the GEM 63's are easier to handle and cost less than their predecessors.
ULA plans to use a beefier version, called the GEM 63XL on its next generation rocket, the Vulcan Centaur, which is currently under construction. By testing a smaller version on the Atlas V, the rocket manufacturer plans to thoroughly test out the GEM's capabilities before strapping one onto a Vulcan.
The NRO hasn't revealed too many details about this launch or its payload. However, warning notices issued to pilots and boaters and a mission profile animation suggest that the rocket is flying on a northeasterly track that will eventually put it in a high-inclination orbit with regular views of the Northern Hemisphere.
Today's launch could be the first of a double header, as SpaceX is preparing to launch its own government payload, an upgraded GPS satellite for the U.S. Space Force. The launch, originally planned for Oct. 2, was scrubbed at the last second when engineers noticed an engine issue.
The team identified the cause of the anomaly, and swapped out two engines on the rocket. If all goes as planned, that launch will blast off from an adjacent launch pad at Space Launch Complex 40 on Thursday evening (Nov. 5). Liftoff is set for 6:24 p.m. EST (2324 GMT), and the launch will be broadcast on Space.com.
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