As SpaceX charges forward with full and rapid rocket reuse, the company's stretch goal is to fly each "ship" every six to eight hours. These "ships" are the Starship launch system's upper stage, which is 50 meters tall and designed to carry payloads into orbit or be refilled there to fly to the Moon or Mars. The first-stage "booster" could fly even more frequently, as much as once an hour, he predicted. The first stage makes a six-minute flight to space and back and is intended to be loaded with propellant on the ground in just 30 minutes. //

SpaceX has unquestionably come a long way since 2016, when Musk first revealed the full scope of his plans to build a launch system that could establish a self-sustaining settlement on Mars. By his own estimates, such a venture would require 1 million tons of food, water, and construction materials. The settlers will need to build an entire industrial base to mine the red planet, and manufacturing consumer products will require a huge infrastructure base to refine and shape materials.

This is an incredible logistical challenge. Consider that throughout the last five decades, during the entirety of its Mars exploration program, NASA has landed a grand total of a couple of tons on the surface of Mars.

For his settlement plan, therefore, Musk proposed an unprecedented rocket and spacecraft. During a 90-minute speech in Guadalajara, Mexico, five years ago, Musk spoke of his “Interplanetary Transportation System,” or ITS. This was a huge and fully reusable launch system with a second-stage spaceship that could be fueled in low Earth orbit and then flown to Mars fully laden with supplies or dozens of settlers. Eventually, after more name changes, the ship would be christened Starship.

The 2016 speech was striking in its candor. Musk laid bare his entire vision for the first time for all the world to see. It was easy to criticize, and many did. The general viewpoint among the established space community at the time was that such a vision was preposterous.

And who could blame the critics? Only four weeks before Musk gave his speech, SpaceX had blown up its second Falcon 9 rocket in a year, losing the Amos-6 satellite on the launch pad on September 1. The company was also going to be years late delivering a Crew Dragon capability to NASA and its astronauts. And for all the talk of reusable rockets, SpaceX had not yet re-flown a single Falcon 9 rocket. Critics watched the Guadalajara speech and saw Musk the Charlatan—over-promising, grasping for government money, and spewing lies about the future when he couldn’t deliver in the present.

But in the five and a half years since Musk’s first Mars moment, the billionaire has answered those critics. SpaceX has not lost a single rocket since Amos-6. In fact, the Falcon 9 booster recently set the record for the longest streak of successful launches by any rocket ever. SpaceX also has become a reliable provider of crew transportation services to NASA, years ahead of its competitor Boeing, which NASA paid 60 percent more for the same service to low Earth orbit. And Falcon 9 rocket first stages have now flown 11 times, with no end in sight.