This makes sense given that the relatively low orbit would SpaceX to bring the Falcon 9 first stage in for a landing back on land, rather than a drone ship at sea.
The Falcon 9 rocket is set to blast-off at 8 p.m. ET from the company's launch pad at Cape Canaveral Air Force Station in Florida. Few details have been released about the classified mission, known as Zuma, other than it includes a satellite built by Northrop Grumman Corp.
The Falcon 9 rocket will carry Zuma, a USA government spacecraft, into low-Earth orbit.
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But now conditions for the mysterious mission are 80-percent go, weather-wise, in Florida.
SpaceX successfully sent something into space for the United States government, and that may be all we'll ever know about the so-called "Zuma" mission that Elon Musk's commercial space company completed from NASA's Kennedy Space Center in Florida Sunday evening.
After launch, SpaceX returned the tall portion of the Falcon 9 rocket to an upright landing at Cape Canaveral.
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The booster's two stages separated 2 minutes and 19 seconds into flight.
It's SpaceX's third classified launch for the US government, this one taking place under a deal with defense contractor Northrop Grumman.
SpaceX has scheduled a live feed of the launch on YouTube (we've embedded it below!) but you can also watch along on Space.com's webcast page. It wasn't until earlier in January that the company was able to confirm a hard time or date for the launch.
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