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UPDATE: April 30K 2017, 7:21 a.m. EDT SpaceX aborted its launch at the last minute on Sunday due to a sensor issue with the first stage of the Falcon 9 rocket. The private spaceflight company will attempt the launch again on Monday at 7 a.m. ET. Webcast here:

SpaceX is getting into the spy satellite game.

On Sunday, Elon Musk's private spaceflight company will launch a rocket loaded with a secret payload for the National Reconnaissance Office, marking the first time SpaceX will have lofted a major national security payload up to orbit for the spy agency. (A Falcon 9 rocket actually launched a couple tiny satellites for the NRO as secondary payloads years ago, but hey, that doesn't count as "major" to us.)

Oh, and did we mention that SpaceX is also planning to land the first stage of its Falcon 9 rocket back on land at Cape Canaveral after sending the spy satellite payload on its way? And that all this will take place early in the morning on Sunday, potentially providing stunning views?

The Falcon 9 is expected to liftoff at 7 a.m. ET on Sunday, though depending on weather and other factors having to do with the rocket, it could launch at any time between then and 9 a.m. ET. The landing of the rocket stage will happen about 9 minutes after the launch.

SpaceX will air the launch and landing live in the window below. The webcast will begin at about 6:40 a.m. ET.

This webcast may be different from other SpaceX broadcasts, however.

As the nation's procuring agency for spy satellites, the NRO is famously secretive about their launches, and this one is no different. No one is quite sure what's traveling to space aboard the Falcon 9 this weekend.

Because of that secrecy, SpaceX will likely need to cut off the broadcast of the Falcon 9's ascent to avoid giving away any clues about the payload to foreign intelligence agencies, and we definitely won't get any views of the actual payload as the first and second stages of the rocket separate.

In all likelihood, the feed will cut off sometime right after liftoff, and we'll just have to follow along with the announcers as the first stage attempts to make its landing back at the Cape.

That said, SpaceX's plan to land its rocket back at the pad in Florida actually tells us a little bit about what might be onboard the rocket.

SpaceX only attempts these kinds of land landings when the Falcon 9 has a fair bit of fuel leftover from its launch. The rocket only has this excess fuel when the payload is either very light, or heavy but going to a low orbit. If the Falcon 9 has less fuel leftover, then the company will attempt to land the rocket stage back on a drone ship in the ocean instead.

It's possible that this NRO payload is a light, experimental satellite or a heavier satellite in a lower orbit, but there's no way of knowing for sure. The industry publication Spaceflight Now has more speculation about this question, if you feel like digging into it ahead of the launch.

If SpaceX manages to land this rocket stage, it will be the fourth time the company has landed a Falcon 9 first stage back on land, and it's always a spectacular, alien looking sight.

Do yourself a favor and tune in to start your Sunday off right.