Launch preparations are well underway, and the countdown remains on track for SpaceX’s 28th cargo resupply launch to the International Space Station for NASA. Just 10 minutes from now, at 11:47 a.m. EDT, the SpaceX Falcon 9 rocket’s nine Merlin engines will roar to life, sending the company’s Dragon on its way to the orbiting laboratory. The spacecraft will deliver critical supplies and equipment that will support dozens of the more than 200 science and research investigations that will occur during Expedition 69.
Coming up in the next few minutes, the Falcon 9 will begin its prelaunch engine chill, which involves flowing a small amount of the super-cold liquid oxygen (LOX) into the Merlin engines’ turbo pumps to avoid thermally shocking the system when the full flow of LOX runs through them.
Following that, Dragon will transition to internal power and the command flight computer will begin its final prelaunch checks, culminating with the SpaceX launch director verifying we are “go” for launch.