Editor's Note: This article was updated Sept. 7 at 9:45 a.m. EDT to reflect a one-day launch delay for the Telstar 18V; it will now launch Sept. 9.
After a successful engine test-fire, SpaceX is on track for a Sunday-night launch of the company's Falcon 9 rocket, which will carry a Telstar communications satellite. The launch was delayed one day to complete pre-flight checkouts, according to a tweet from SpaceX.
SpaceX lit the rocket's nine engines for a short static-fire test Sept. 5, later confirming on Twitter a Saturday (Sept. 8) launch date from the company's launch site at Cape Canaveral Air Force Base in Florida. The launch has faced multiple delays, but its new 4-hour launch window was set for 11:28 p.m. EDT Saturday (0328 on Sunday GMT), according to a report from Spaceflight Now. Its new launch window Sept. 9 should be in a similar time window.
Next, engineers will have to attach the rocket's payload: the Telstar 18 Vantage communications satellite (Telstar 18V for short), which will be shared between the Canadian company Telesat and Hong Kong's APT Satellite Co. Ltd. SpaceX successfully launched the Telstar 19V, the second satellite in this series, in July; Telstar 18V will be the third in the series, according to a release from Telesat.
Like 19V, the newest Telstar will launch on SpaceX's latest (and final) iteration of the Falcon 9 rocket, the Block 5. The satellite will reach a high geostationary orbit, meaning it will stay still compared to a specific spot on Earth as the planet turns. Once there, the Telstar 18V will aid communications from India and Pakistan all the way to Hawaii, with a potential mission length of more than 15 years, according to Telesat.
For now, the official weather forecast from the U.S. Air Force suggests a 60 percent probability of favorable launch conditions.
SpaceX's last Telstar launch, in July, reused the Block 5 first stage; the upcoming launch will employ an unused rocket. As usual, SpaceX will attempt to land the first stage to reuse again, this time on the company's drone ship named Of Course I Still Love You, according to Spaceflight Now.