Starship is about to embark on its fifth flight, and this time there's a catch

“We landed in the ocean within half a centimeter, so we think we have a reasonable chance of returning to the tower,” Gerstenmaier said.

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The Starship's upper stage, meanwhile, will fire six Raptor engines to accelerate to near-orbital speed, giving the rocket enough power to sail halfway around the world before falling back into the atmosphere above the Indian Ocean.

This is a similar trajectory to the one Starship flew in June, when it survived a fiery reentry for a controlled landing. It was the first time SpaceX completed an end-to-end Starship test flight. Onboard cameras showed fragments of the Starship's heat shield falling from the Starship as it reentered the atmosphere, but the vehicle retained control and restarted its Raptor engines, turned from a horizontal to a vertical orientation and settled into the Indian Ocean , northwest of Australia.

After analyzing the results of the June mission, SpaceX engineers decided to rework the heat shield for the next Starship vehicle. The company said its technicians spent more than 12,000 hours replacing the entire thermal protection system with new-generation tiles, a backup ablative layer and additional protection between the ship's valves.

Sunday's test flight should take about 1 hour and 5 minutes from start to finish.

This diagram illustrates the path the Super Heavy booster will take to return to the launch pad in Texas, while the Starship's upper stage continues its ascent to space.

Credit: SpaceX

Here's a look at the key events from Sunday's flight:

• T+00:00:02: Launch

• T+00:01:02: Maximum aerodynamic pressure

• T+00:02:33: Super Heavy MECO (most engines fail)

• T+00:02:41: Phase separation and ignition of Starship engines

• T+00:02:48: Super heavy boost back burn start

• T+00:03:41: Super heavy duty boost back burn shutdown

• T+00:03:43: Throwing hot staging overboard

• T+00:06:08: Super Heavy is subsonic

• T+00:06:33: Fire start during super heavy landing

• T+00:06:56: Super heavy landing, takedown and catch attempt

• T+00:08:27: Spaceship engine shut down

• T+00:48:03: Return of the spaceship

• T+01:02:34: A spaceship is transonic

• T+01:03:43: The spaceship is subsonic

• T+01:05:15: Spaceship landing flip

• T+01:05:20: Burn during spaceship landing

• T+01:05:34: The crash of a spaceship in the Indian Ocean

SpaceX officials hope Starship's heat shield will remain intact as it plunges into the atmosphere, when temperatures will reach 2,600° Fahrenheit (1,430° Celsius), hot enough to melt aluminum, the metal used to build many launch vehicles. SpaceX chose stainless steel for Starship because it is strong at cryogenic temperatures (the rocket consumes super-cold fuel and oxidizer) and has a higher melting point than aluminum.