We’re not yet in the phase where a shuttle launch is a common weekly or monthly thing, but from time to time we get to see how the Discovery shuttle comes back on the planet or how it takes off to go back in space.

Tomorrow at 11:38 Eastern time, if the weather is good at the Kennedy Space Center the Discovery is scheduled to take off on the STS-120 mission to the International Space Station but predictions are not great, going from 60% favorable to 60% unfavorable. Other than the weather, no problems are keeping the shuttle on grounds and officials said that they want it back in space as soon as possible, but taking the safest decisions.

The mission is all wrapped around the delivery of the Harmony module, which is an Italian made Aluminum tube, that will connect the European lab Columbus and Japan’s Kibo lab on the International Space Station. This is a very big step before we have the final shape of the space station, and is Commander Pam Melroy, 46, the second woman in command of the Discovery that should have the job done.

If you’ve booked tickets to see the launch live, make sure you have enough cash, a rain coat and an open ticket back home.