The latest SpaceX resupply mission to the International Space Station is set to lift off at 6pm US Eastern Time today. The Falcon 9 launch vehicle will be sending a Dragon capsule into orbit to bring over 5,000 lbs of supplies and science experiments to the ISS. If all goes according to plan, the Dragon will rendezvous with the Station early Wednesday morning (also US Eastern).

This is SpaceX's third resupply mission, so parts of the liftoff and rendezvous are likely to be routine. Lately, however, SpaceX has been doing interesting things with its Falcon boosters after payload separation. Back in September, the Falcon flipped around in flight and fired its engines to reverse direction, the first step toward a controlled return to the atmosphere.

This time around, the company is planning on expanding on that test. "During today’s launch SpaceX will attempt to recover the first stage of the Falcon 9 launch vehicle as part of SpaceX’s reusability program," a SpaceX spokesperson told Ars. "It’s important to note this is not a primary mission objective and the probability of recovering the first stage is low, maybe 30-40 percent."

The attempt will see the Falcon repeat the flip-and-burn that slows it for reentry and then ignite a single engine to slow it during its descent. During this burn, the legs that may eventually allow it to land safely will be deployed to test their effect on the aerodynamics of the descent. In this case, the Falcon will land in the water, so the legs won't be involved in an actual touchdown. The long-term goal, however, is to land Falcons on land and send them back to space multiple times, a process that should greatly reduce launch costs.

NASA TV will be broadcasting the launch. Check back closer to launch time, and we'll try to embed a livestream.

Update (4/14 at 3:49p Central time):

NASA and SpaceX cancelled the launch attempt today due to a Helium leak on Falcon 9. The organization says a fix will be implemented by the next opportunity to launch on 4/18. According to Orlando's WFTV, NASA debated scrapping the launch through the weekend due to a critical backup computer failure from Friday. NASA decided yesterday that the launch could go on before ultimately canceling around 3:45 pm Eastern time today.