After a weather delay, SpaceX will once again try to land the first stage of its Falcon 9 rocket on an ocean barge off Florida Thursday. Returning a rocket on land is one thing, but no company has completed an ocean landing. SpaceX has tried, and failed, three times before Thursday’s attempt.
The 90-minute launch window from Space Launch Complex 40 at Cape Canaveral Air Force Station is scheduled to start at 6:46 p.m. EST with the SpaceX live-streaming starting at 6:26 p.m. EST.
SpaceX’s latest ocean-landing attempt took place in January after the launch of NASA’s Jason-3 satellite. The rocket reached the platform, but one of the latches failed to lock into place. The small glitch caused the rocket to tip over and explode. The landing attempts on land and sea by SpaceX are not requirements for its contracts with NASA or commercial partners, but part of the company’s larger mission is to create a reusable rocket that would significantly reduce launch costs.
While ocean landings are more difficult than ground-based returns, Thursday’s launch is further complicated by the launch requirements. The three previous ocean-landing attempts occurred after launches to altitudes several hundred miles above Earth. Last month’s launch placed NASA’s ocean-monitoring satellite in an orbit 830 miles above Earth. Thursday’s launch of the SES-9 communications satellite could reach an altitude of 16,155 miles.
SpaceX successfully returned the first stage of the Falcon 9 rocket, which contains the Merlin 1D engines and propellant tank, in December after launching 11 small satellites for ORBCOMM. Jeff Bezos’ Blue Origin accomplished the feat during a test flight of its New Shepard space vehicle Nov. 24. Blue Origin successfully launched and landed the same space vehicle Jan. 23. The launch and return of a reusable rocket occurred during a test flight at an altitude of 62 miles. SpaceX is the only commercial spaceflight company to perform ocean-landing attempts.
The SpacX live stream can be viewed below. There’s a hosted broadcast and a technical broadcast that provide additional information for the launch.