SpaceX’s Starship megarocket prepares for launch after two cancellations

Test flight comes after explosive failures raise doubts over founder Elon Musk’s goals to reach Mars and moon

SpaceX for a third time on Tuesday prepared to launch its Starship megarocket after scrubbing the launch twice in two days.

The 10th test flight comes after a string of explosive failures that have raised doubts about whether the world’s most powerful launch vehicle can fulfill founder Elon Musk’s vision of colonizing Mars or helping Nasa return astronauts to the moon.