Artemis I Update: Countdown is Underway for Wet Dress Rehearsal

At approximately 5 p.m. EDT today, the launch team arrived at their stations inside the Launch Control Center at NASA’s Kennedy Space Center in Florida. The countdown will begin 30 minutes later at 5:30 p.m. or L-45 hours, 10 minutes before the initial target T-0 for the wet dress rehearsal test for NASA’s Artemis I mission. Teams are proceeding with a modified test, primarily focused on tanking the core stage and minimal propellant operations on the interim cryogenic propulsion stage (ICPS) with the ground systems at Kennedy. Tanking operations are scheduled to occur on Thursday, April 14.

Meteorologists with the U.S. Space Force 45th Space Wing predict favorable weather for propellant loading operations.  Weather constraints stipulate there must be less than a 20% chance lightning within 5 nautical miles of pad during the first hour of tanking. Winds also must not be above 37.5 knots and the temperature cannot be below 41 degrees Fahrenheit.

Overnight, teams will power up Orion and the Space Launch System core stage, charge core stage battery, and prepare the four RS-25 engines, which will not be lit during the test.

During the test, the timing for some events on account of several planned operational demonstrations tied to specific capabilities and test objectives may differ from the day of launch countdown. These demonstrations include tests on the cryogenic systems and an approximately three-minute hold inside the terminal count, which would not normally occur on launch day. If needed, the test team may also hold as necessary to verify conditions before resuming the countdown, or use the test window or extend beyond it, if consumables and resources allow them to complete test objectives.

In addition to updates on this blog, NASA will provide live updates on the Exploration Ground Systems Twitter account. NASA is also streaming live video of the rocket and spacecraft at Launch Pad 39B on the Kennedy Newsroom YouTube channel. Activity at the launch pad will likely not be visible during the majority of the countdown, but some venting may be seen during tanking on April 14.

The next operational update will be posted the morning of April 13.