If all goes as planned, a SpaceX rocket will lift off from the Cape Canaveral Air Force Station in Florida on Sunday. A two-hour launch window begins at 8 p.m. ET. The space exploration firm, which is headed by Tesla () CEO Elon Musk, initially scheduled the secretive Zuma mission for last November, but a series of delays pushed it back.
SpaceX gave some reasons for the schedule changes. At one point, SpaceX said it was delaying the mission for “fairing testing.” The fairing is the very top portion of the rocket that houses the payload. “Extreme weather” also slowed down the company’s launch preparations.
Last week, SpaceX finally declared that both the rocket and the payload were “healthy” and ready for launch.
Zuma is headed for low-Earth orbit, but we don’t know exactly where. SpaceX will likely cut off its customary live stream of the launch early in order to avoid dropping any hints about the spacecraft’s final destination. It has done so during other secretive missions.
Zuma was built for the U.S. government, and it’s not unusual for the government to keep information about sensitive payloads under wraps. Typically these payloads involve a military concern, such as national security, defense or surveillance.
When asked about the project in November, Northrop Grumman () — the Virginia-based aerospace and defense company that says it’s “involved” in the Zuma mission — declined to give any details about the spacecraft or reveal which arm of the government funded it.
Friday’s launch marked SpaceX’s 18th and final launch for the 2017 calendar year, making it the busiest private-sector rocket company in the world.
The mission was to deliver a group of 10 telecommunications satellites to low-Earth orbit for a company called Iridium, which is in the process of replacing its vast satellite network. It’ll be used to deliver communications services and, among other things, track airplane traffic.
Musk took advantage of the buzz created by Friday’s spectacle to tout SpaceX’s next big feat: conducting a test launch of its massive new rocket, called Falcon Heavy. That’s due in January.
“If you liked tonight’s launch, you will really like Falcon Heavy next month: 3 rocket cores & 3X thrust. 2 cores return to base doing synchronized aerobatics. 3rd lands on droneship,” Musk tweeted.
To translate, “rocket cores” refer to the boosters at the base of the rocket. They provide the initial thrust at liftoff. SpaceX’s defining move is to guide those boosters back to Earth for a safe landing so they can be reused in future missions.
The Falcon Heavy has three boosters, two more than SpaceX’s operational Falcon 9 rocket, and SpaceX will attempt to recover all of them.
Droneship refers to a landing pad that SpaceX sends into the ocean to capture boosters that fly out with a horizontal trajectory.
Reusing hardware is all part of SpaceX’s plan to drastically drive down the cost of spaceflight, and the company has all but mastered the move. It’s landed rockets on 20 separate occasions.
No rocket landing was attempted on Friday, however.
Photo credit: SpaceX