Update, March 15: A new launch window is opening this evening/morning, at roughly the same time.

At about 1:30am Florida time (5:30am UK time), SpaceX hopes to send a communication satellite to a geostationary transfer orbit. The launch, scheduled to take place from the Kennedy Space Center, would mark one of the last times the company doesn't make an attempt to recover and reuse a booster.

As Ars' Eric Berger detailed, the payload is a large communication satellite, EchoStar XXIII, which will ultimately reside in a high, geostationary orbit. The combination of altitude and weight means that the existing Falcon 9 rocket will burn much of its fuel on the way up, leaving an insufficient supply to land. SpaceX plans to upgrade the Falcon 9 later this year to a version that could be recovered even from launches of this sort.

The launch will take place from Launch Complex 39A at Kennedy, which NASA had used for Apollo and Shuttle missions. If all goes well, the satellite will be deployed about a half hour after launch. The launch window can accommodate about two-and-a-half hours of delays. If that's not sufficient, SpaceX will have to wait until Thursday to try again.