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SpaceX is preparing to launch the 12th uncrewed test flight of its Starship rocket as soon as Thursday, marking the debut of the upgraded Starship V3 — the largest and most powerful version of the vehicle yet — ahead of a planned IPO that could be the biggest in history.

A 90-minute launch window beginning at 6:30 p.m. EDT Thursday has been set for liftoff from SpaceX's Starbase site in South Texas, Space.com reports. Designated Flight 12, the mission will be the inaugural Starship test of the year — with no flight having taken place since last October.

SpaceX said it will not attempt to recover either portion of the vehicle from this launch. Roughly seven minutes into the flight, the Super Heavy booster will execute a descent and hit the water in the Gulf of Mexico; the upper stage will follow with its own ocean entry in the Indian Ocean around an hour after liftoff. Prior to each water impact, the booster and upper stage are each scheduled to fire their engines in a braking maneuver. The payload manifest includes 20 Starlink stand-ins alongside a pair of satellites that have been outfitted with cameras to image the heat shield as the vehicle descends through the atmosphere, SpaceX said.