• A view of the Falcon 9 rocket on Sunday morning, ready for launch. Trevor Mahlmann/Special to Ars
  • And then the fog lifted. Trevor Mahlmann/Special to Ars
  • A zoomed-in view of Landing Zone 4. Trevor Mahlmann/Special to Ars
  • A view of the launch site, right, and landing site (left). Trevor Malhmann/Special to Ars
  • Our photographer on the scene, Trevor Mahlmann, is ready to capture views of the launch and landing. Trevor Mahlmann/Special to Ars
  • Some of the SpaceX facilities at Vandenberg. Trevor Mahlmann/Special to Ars
  • SpaceX will attempt to use its new landing site at Vandenberg Air Force Base on Sunday night. SpaceX
  • The structure in the lower, left-hand corner is a booster stand where initial inspections of the first stage will occur. SpaceX

The US Air Force has a message for residents of Santa Barbara, Ventura, and San Luis Obispo counties—do not be alarmed on Sunday night around 7:30pm local time if you hear a loud noise. That's just the sonic boom of a rocket's first stage, returning from space, and landing for the first time ever at site along the West Coast of California.

On Sunday night, SpaceX is scheduled to launch a Falcon 9 rocket from Vandenberg Air Force Base in California, which is a couple of hours north of Los Angeles. While the company has landed several first stage boosters on a drone ship offshore from California, until now it has not attempted to land at a site along the coast. But now it has completed the "Landing Zone 4" facility and received the necessary federal approvals for rockets to make a vertical landing there.

For long time employees of the Hawthorne, Calif.-based company there must be some satisfaction in this. More than a decade ago, when SpaceX sought to begin launching its Falcon 1 rocket, the company asked the Air Force for permission to launch from Vandenberg. But the military and some of the companies using the facility to launch national security missions, including Lockheed Martin and Boeing, looked coolly upon the requests from SpaceX. Now SpaceX has built a landing zone on the former site of Space Launch Complex 4W, where Titan rockets built by Lockheed were previously launched.

This will be SpaceX's 17th launch attempt this year, bringing the company close to tying its record-setting pace of 18 launches last year. With as many as half a dozen launch attempts left this year, SpaceX should easily surpass its 2017 total, barring a major accident.

This Block 5 first stage of the Falcon 9 rocket has previously flown once before, launching 10 Iridium NEXT satellites into a polar orbit 625km above the Earth. It returned to a drone ship off the West Coast after that flight. The payload launching Sunday night, the SAOCOM 1A satellite for Argentinas Space Agency, weighs less than a lot of the Falcon 9 payloads launched into a Sun synchronous orbit several hundred kilometers above the Earth. Therefore, the first stage will have ample fuel to return to the new coastal landing site.

SpaceX is also likely to try and retrieve one-half of the Falcon 9 rocket's payload fairing. It has come close to catching these before with its large, catcher's-mitt shaped net attached to a boat, but it has yet to succeed.

For Sunday night's attempt, the instantaneous launch window opens at 7:21pm PT (02:21 UTC on Monday). The landing (and sonic booms) should occur less than eight minutes later. A back-up launch window is available on Thursday night, at the same time. The webcast below should begin about 15 minutes before the window opens Sunday night.

SAOCOM 1A launch.

Listing image by Trevor Mahlmann/Special to Ars

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