At last second, SpaceX delays satellite launch again

Still, the company says it will make another attempt at a historic first, landing an orbital rocket on a sea-based platform.

A third try at a SpaceX launch for a communications satellite is set for 6:47 p.m today at Cape Canaveral.

This will be SpaceX fourth attempt at such a landing, and while the company has stated that it has low expectations of success, these rocket landings are a novelty of 21st century spaceflight and worth getting excited about. The relay station, which will provide video and data services across the south Asia-Pacific region, is the first of three comsats SES hopes to launch aboard SpaceX rockets this year. SpaceX noted this on its Twitter as a “range safety issue” and Elon Musk tweeted that they were scrambling to get the boat to move. A new launch date was not announced.

The launch will be coupled with a first stage landing attempt on SpaceX’s autonomous drone ship. Thursday’s countdown was aborted at 6:45 p.m., two minutes before liftoff, according to SpaceX’s online webcast.

SES has more than 50 satellites already in orbit and the launch of SES-9 will expand its capacity, company officials said.

The decision to abort was made in the final seconds of the countdown. The rockets now run on deep cryo liquid oxygen (LOX). It is only the second booster upgraded by SpaceX to utilize super-cooled, “densified”, propellants that allow the rocket to carry more RP-1 kerosene fuel and liquid oxygen propellant. SpaceX President Gwynne Shotwell said February 3 that after the SES-9 launch, the company planned to launch “every two to three weeks” to handle a backlog of commercial and NASA missions. SpaceX, the company responsible for the satellite into orbit, gave no explanation.

The Falcon 9 will need to achieve a height of 22,000 miles above Earth before separating from its payload, after which it will attempt to land onto a floating barge in the Atlantic Ocean.

“…given this mission’s unique GTO profile, a successful landing is not expected.”