Update update: everything looks good for a launch today!

Update: Due to a helium leak, today's launch has been scrapped. It is tentatively scheduled for 3:25 pm EDT on Friday, assuming they can resolve the problem by then.

Watch the launch LIVE here:

Live streaming video by Ustream

Today at 3.25 EDT, SpaceX is launching a Falcon 9 rocket from Cape Canaveral in Florida that will bring supplies to the ISS. The Dragon capsule will dock with the ISS on Wednesday. This launch date has been pushed back several times due to hardware issues, but so far, everything looks good and the launch is currently a go.

There are a few amazing things associated with this mission: the payload itself, and what to do with the rocket after the capsule detaches.

Astronauts onboard the ISS will soon be able to grow their own vegetables in space using a specialized system of LED lights. If successful, this will help astronauts not only at the ISS in addition to future long-term missions to Mars and beyond. Sending seeds rather than prepackaged food will not only reduce the cargo sent up to astronauts (which reduces cost). It will also give astronauts better nutrition as well as the relaxation associated with tending the garden.

Various high-definition cameras will be sent to the astronauts for the purpose of taking videos of the Earth. It will then be decided which camera(s) is(are) superior and will continue to be used.

The most amazing payload being launched today is the Optical Payload for Lasercomm Science (OPALS) system. Communication between the ISS and Earth are done using radio frequencies, but this new system will use lasers. Some advantages (aside from the fact that communicating through lasers is incredibly cool) are that more information will be able to be sent in a beam, as lasers have considerably shorter wavelengths than radio waves, and it doesn’t use much power.

After delivering the payload, the rocket itself has a big test ahead of it: the ability to safely land back on Earth. SpaceX has been working toward a rocket that is reusable and can land on a set of legs as precisely as it can take off. There have been trials of this system making small launches (going less than a kilometer into the air) but this is the next step in making the landing gear functional.

For this launch, however, the team isn’t even attempting to reuse the rocket; they just want to make sure the landing legs will deploy when they are supposed to. The rocket will land in the Atlantic Ocean, so there is virtually no danger if the trial doesn’t work. Realistically, the odds of this landing being successful are pretty low at only 30-40%. No matter what the outcome of the trial, the scientists will gain information to keep moving forward toward a reusable rocket.