NASA’s new rocket, the Space Launch System (SLS), made its way to Launch Pad 39B last Thursday evening for final testing before launching the Artemis I mission to the Moon.
The journey began at the Vehicle Assembly Building (VAB), where the SLS rocket was assembled and “stacked” atop the Mobile Launch Platform (MLP). The Crawler Transporter then picked up the MLP with SLS and began the 4-mile journey to the launch pad. At 322 feet tall and weighing 3.5 million pounds, the Crawler makes the journey at a blistering 0.8 mph. After 10 hours 28 minutes, the fully stacked SLS arrived at Launch Pad 39B at 4:15 am Friday morning.
Now at the launch pad, the SLS will undergo a Wet Dress Rehearsal (WDR). Launch teams will practice loading and unloading propellant into the SLS to finalize timelines for launch. The teams will conduct a full launch countdown, taking the clock all the way down to main engine start, then halt the clock and recycle back to T-10 minutes. They will start the countdown again and once again halt the count at T-10 seconds to simulate a launch scrub. Finally, the teams demonstrate the ability to safely drain propellant from the rocket.
WDR testing should take approximately two days. Once completed, the SLS will be transported back to the VAB to remove testing equipment, charge spacecraft and rocket batteries, and load final cargo. Teams will review the data from the WDR to determine a final launch date. Once that is set, the SLS will roll back to the launch pad for the final time about a week before launch.
