At 12:47 pm UTC on the 10th of September 2023, a United Launch Alliance Atlas V lifted off from Space Launch Complex 41 in Cape Canaveral, Florida. United Launch Alliance provided coverage of the launch up until main engine cutoff on the first stage at the request of the customer.
SILENTBARKER, also called NROL-107, is a mission between the National Reconnaissance Office and the United States Space Force. Not much is known about the satellite onboard other than it is likely heading to geosynchronous orbit. United Launch Alliance states the following use for the satellite in an update on its website;
SILENTBARKER/NROL107 meets the Department of Defense and Intelligence Community (IC) space protection needs by providing the capability to search, detect and track objects from a space-based sensor for timely custody and event detection. Surveillance from space augments and overcomes existing ground sensor limitations with timely 24-hour above-the-weather collection of satellite metric data only possible with a space-based sensor and then communicates its findings to satellite operators, analysts, and other mission users.
The NRO and the USSF have a shared interest to strengthen the nation's SDA and Indication & Warning (I&W) capabilities to enable timely decision making and unity of effort to defend the DoD and IC critical capabilities against current and projected threats. SILENTBARKER/NROL107 will strengthen the NRO's ability to provide a wide range of timely intelligence information to national decision makers, warfighters and intelligence analysts to protect the nation's vital interests and support humanitarian efforts worldwide.
The Atlas V for this rocket is in the 551 configuration meaning it has five solid rocket boosters, a five-meter diameter fairing, and one RL10C-1-1 engine on the Centaur stage.
What is Atlas V?
Atlas V is an expendable medium-lift launch vehicle manufactured and launched by United Launch Alliance. Atlas V first flew on the 21st of August 2002 and has since flown ninety-seven times, all successfully.
The first stage of the Atlas V is powered by an RD-180 rocket engine burning kerosene and Liquid oxygen for up to two hundred and fifty-three seconds and generating 423 tons of thrust. Atlas V can also be configured with up to five GEM 63 solid rocket boosters burning Hydroxyl-terminated polybutadiene for ninety-four seconds and generating 170 tons of thrust each. The upper stage of the Atlas V, called Centaur, is powered by either one or two RL10 rocket engines producing 10 tons of thrust each. The Centaur upper stage can burn for up to eight hundred and 42 seconds and is fuelled by liquid hydrogen and liquid oxygen. Atlas V can also be configured with either a 4.2-meter payload fairing or a 5.4-meter payload fairing depending on the size of the payload.
Atlas V can launch up to 18,850 kilograms to low Earth orbit or 8,900 kilograms to geosynchronous transfer orbit depending on the configuration.