SpaceX Set to Launch Final Inmarsat Global Xpress Satellite

The fourth GX satellite will be launched into orbit on a Falcon 9 rocket, which will not make a return trip.

Arguably the most exciting aspect of SpaceX's most recent launch was watching the first stage of the Falcon 9 rocket return to Landing Zone 1 (especially with the split-screen footage). Unfortunately, Monday night's SpaceX launch won't feature that same excitement, because this Falcon 9 rocket won't have enough fuel to make a return trip.

That's because, after a series of delays, SpaceX is finally sending the Boeing-built Inmarsat-5 Flight 4 communications satellite into Geostationary Transfer Orbit, and the weight of the satellite (13,400-lbs.) will require all of the rocket's thrust.

As SpaceX confirmed in a tweet, the Falcon 9 rocket is erect and ready to take off from Pad 39A at Kennedy Space Center, with a launch time of 7:21 p.m. ET and a 49-minute window. The launch can be viewed live on SpaceX's YouTube channel (above).

The Inmarsat-5 F4 is the fourth and final satellite in the $1.6 billion Global Xpress system that "has been delivering seamless, high-speed broadband connectivity all around the world since December 2015," according to the company's website. The first I-5 satellite was launched in 2013, while the second and third went up in 2015.

While SpaceX fans may be disappointed that this Falcon 9 rocket won't return, this type of mission will soon be the exception. As former SpaceX official Phil Larson told Gizmodo, "Expendable missions will start to become few and far between." This will be SpaceX's sixth launch of 2017.