Tonight at 11:50pm ET, SpaceX will be launching their final Cargo Dragon spacecraft, ending the second round of the Commercial Resupply Service (CRS) contract with NASA.
Dragon is currently loaded with roughly 4,500 pounds of supplies and payloads, including materials to support more than 250 research investigations being conducted on the ISS currently.
This particular Dragon previously supported the CRS-10 and CRS-16 missions and the booster supported the CRS-19 mission. After launch, the first stage will boostback and land back at LZ-1 about 8 minutes after.
You can watch the launch live at www.spacex.com/webcast start about 15 minutes prior to liftoff.