Update for 5:12 pm ET: SpaceX is now targeting a 6:12 p.m. EDT (2212 GMT) launch time for its Falcon 9 rocket carrying two SES satellites for ViaSat. The mission's 88-minute launch window opened at 5:12 pm ET.
SpaceX will launch two satellites for the telecom company SES today (April 28) and land a rocket at sea, weather permitting, and you can watch the action live.
A Falcon 9 rocket carrying SES' O3b mPower 3 and 4 satellites is scheduled to lift off from Florida's Cape Canaveral Space Force Station Friday during an 88-minute window that opens at 5:12 p.m. EDT (2112 GMT).
Watch it live here at Space.com, courtesy of SpaceX, or directly via the company. The webcast is expected to begin about 15 minutes before launch.
That schedule assumes good weather, however, and Mother Nature may not cooperate. Indeed, forecasts project just a 20% chance of good conditions at launch time on Friday, SpaceX said via Twitter yesterday (April 27). If Friday's try is scrubbed, a backup opportunity opens on Saturday (April 29) with the same 88-minute window.
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If everything goes according to plan, the Falcon 9's first stage will return to Earth just under nine minutes after liftoff today. It will come in for a vertical touchdown on the SpaceX droneship Just Read the Instructions, which will be stationed in the Atlantic Ocean off the Florida coast.
It will be the second liftoff and touchdown for this particular booster, acccording to a SpaceX mission description. It previously launched Crew-6, SpaceX's most recent astronaut mission to the International Space Station for NASA.
The Falcon 9's upper stage, meanwhile will continue hauling O3b mPower 3 and 4 to medium Earth orbit. The two satellites are scheduled to be deployed seven minutes apart about two hours after launch.
As their names suggest, the two satellites launching today will become the third and fourth members of SES' O3b mPower constellation, which will provide low-latency communications services to customers around the word, according to Luxembourg- and France-based SES.
The 11-satellite network is being assembled at an altitude of 5,000 miles (8,000 kilometers). Two satellites are already up there — O3b mPower 1 and 2, which launched on a Falcon 9 last December. That was a landmark mission for SpaceX, the 200th orbital flight for the company since its 2002 founding.
Today's liftoff will be the 29th of 2023 already for SpaceX, with more coming soon. Indeed, the company plans to launch its powerful Falcon Heavy rocket for the sixth time ever this evening, weather permitting. (It's also slated to fly from Florida's Space Coast.)
Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook.