Update for 8:27 pm ET: SpaceX successfully launched the mysterious Zuma spacecraft for the U.S. government on Sunday, Jan. 7, at 8 p.m. ET. Read our full wrap story (and see the Falcon 9 first stage landing) here: SpaceX Launches Secret Zuma Mission for US Government, Lands Rocket

Original story:

SpaceX plans to launch the secret Zuma payload for the U.S. government this evening (Jan. 7), after a nearly two-month delay.

Zuma is scheduled to lift off atop a two-stage Falcon 9 rocket from Florida's Cape Canaveral Air Force Station tonight between 8 p.m. and 10 p.m. EST (0100 to 0300 GMT on Jan. 8). You can watch it live here at Space.com, courtesy of the company. You can also watch the liftoff directly from SpaceX's live webcast page here.

Sunday's launch will also include a landing attempt by the Falcon 9's first stage, which will come back down to Earth at Landing Zone 1, a SpaceX facility at Cape Canaveral. To date, SpaceX has pulled off 20 such first-stage landings, which are part of its push to develop fully and rapidly reusable rockets. [SpaceX's Zuma Launch: Here's What We Know]

Zuma is a U.S. government spacecraft headed to low-Earth orbit. But that's pretty much all that outside observers know about it; everyone involved with the mission has remained pretty tight-lipped.

Sunday's launch was originally slated to take place in mid-November, but SpaceX stood down to investigate the results of payload-fairing testing done for another customer. (The payload fairing is the nose cone that protects a spacecraft during liftoff.)

The company then aimed to loft Zuma on Friday (Jan. 5) but ended up pushing things back by two additional days.

"Team at the Cape completed additional propellant-loading tests today," SpaceX representatives wrote on Twitter Thursday (Jan. 4). "Extreme weather slowed operations, but Falcon 9 and the Zuma spacecraft are healthy and go for launch — now targeting Jan. 7 from Pad 40 in Florida."

That rough weather was presumably linked to the "bomb cyclone" storm that has been battering the U.S. East Coast all week.

Zuma is the third classified launch for the U.S. government by SpaceX. In 2017, the company launched a secret spy satellite for the U.S. National Reconnaissance Office and the X-37B robotic space plane on a classified mission for the U.S. Air Force.

Visit Space.com at 8 p.m. EST (0100 GMT) tonight for complete coverage of SpaceX's Zuma mission. If you capture an amazing photo or video of SpaceX's Falcon 9 launching into the Florida night sky and want to share it with Space.com and our news partners for a story or gallery, send images and comments in to: spacephotos@space.com.

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