WASHINGTON — SpaceX conducted its second mission of the year Jan. 31, launching the GovSat-1 satellite for fleet operator SES and the government of Luxembourg on a previously flown Falcon 9 rocket.

The launch took place at 4:27 p.m. Eastern from the recently opened Space Launch Complex 40 at Cape Canaveral Air Force Station, Florida.

GovSat-1 separated from the Falcon 9’s upper stage 33 minutes after liftoff.

SES, which was the first to trust one of its satellites to a previously flown Falcon 9 booster, has now gone that route three times, more than any other SpaceX customer.

GovSat-1 is part of a joint venture between SES and the Luxembourg government for secure military communications over Europe, the Middle East and Africa, as well as parts of the Atlantic and Indian Oceans. The public-private venture’s first satellite has 68 transponder-equivalent units of 36 MHz capacity each, and counts the North Atlantic Treaty Organization among its first customers. The X- and Ka-band satellite was built by Orbital ATK on the company’s new GEOStar-3 platform.

SpaceX did not attempt to land the rocket’s first stage on a droneship or back at the Cape.

Elon Musk, SpaceX’s founder, tweeted a photo of the booster partly submerged in the Atlantic Ocean, saying “[t]his rocket was meant to test very high retrothrust landing in water so it didn’t hurt the droneship, but amazingly it has survived. We will try to tow it back to shore.”

This rocket was meant to test very high retrothrust landing in water so it didn’t hurt the droneship, but amazingly it has survived. We will try to tow it back to shore. pic.twitter.com/hipmgdnq16 — Elon Musk (@elonmusk) January 31, 2018

The booster was part of SpaceX’s “Block 3” iteration designed to fly no more than two or three times. SpaceX plans to introduce a Block 5 booster this year durable enough to fly as many as 10 missions or more.

SpaceX’s next mission is the much-anticipated Falcon Heavy on Feb. 6 from Cape Canaveral. Additional commercial missions in February include two Falcon 9 missions for Spanish satellite operators — one from Vandenberg for Hisdesat’s Paz radar satellite, and another from Cape Canaveral for the Hispasat 30W-6 communications satellite.

Wednesday’s mission was SpaceX’s first launch since the classified Zuma mission ended with questions about whether the payload reached its orbit. SpaceX said Falcon 9 performed as planned during the Jan. 7 mission, an assertion that shifted focus to Northrop Grumman, which provided the payload and payload adapter.

Not long after the launch, SpaceX customers Iridium and SES said the Zuma mission hadn’t shaken their confidence in Falcon. The Air Force said it saw no reason to revisit Falcon 9’s certification to carry national security payloads.