The U.S. Space Force has approved the launch of a SpaceX Falcon 9 rocket Monday between 3:28 and 7:28 p.m., carrying the NROL-172 mission to low-Earth orbit from Space Launch Complex 4 East at Vandenberg Space Force Base.

If needed, a backup opportunity is available on Tuesday, May 12 at 3:15 p.m., officials reported.

The NROL-172 mission is a classified national security launch by the National Reconnaissance Office (NRO) and U.S. Space Force, and is the 13th mission for the NRO’s “proliferated architecture,” deploying smaller reconnaissance satellites designed for enhanced Earth observation, aiming for high resiliency and rapid revisit capabilities

Following stage separation, the first stage booster will return and touch town on the Of Course I Still Love You droneship stationed in the Pacific Ocean for later retrieval.

There is the possibility that residents of Santa Barbara, San Luis Obispo, and Ventura counties may hear one or more sonic booms during the launch, depending on weather and other conditions, base officials said.

This is the second flight for the first stage booster supporting this mission, which previously launched one Starlink mission.

A live webcast of the mission will begin about 10 minutes prior to liftoff is accessible at www.spacex.com/launches/nrol172, and via webcast on the new X TV app.

Launch dates and times are subject to change at any time due to mission requirements.