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Robert Zubrin, likely the planet's leading strategist for landing humans on Mars, and then remaking it in the Earth's image, predicts SpaceX's colossal Starship will be the first spacecraft ever to speed astronauts to the Red Planet.
Yet Dr. Zubrin tells me SpaceX founder Elon Musk's target date to launch these trailblazing interplanetary astronauts - 2028 - will be virtually impossible to realize, and predicts they might actually touch down in the summer of 2031.
With his remarkable series of books sketching out the rockets and robots that could set the stage for the human exploration and transformation of Mars - which have reshaped future spaceflight masterplans by NASA and by SpaceX creator Elon Musk - Zubrin is widely considered the supreme conceptual architect of creating a New-World Martian civilization.
One of the top aeronautical engineers in the U.S., who co-designed an early version of NASA's powerful Space Launch System rocket, Zubrin forecast on the eve of SpaceX's Test Flight 8 of its next-generation Starship that the super-spacecraft will chart rapid progress this year.
With the new test flight, he said, "I'm hoping they can actually make orbit this time but if they don't they'll make it the next time."
"This is going to happen," Zubrin added, "they will be orbital this year for sure."
One day later, the Starship saw its Super Heavy booster perform perfectly before being captured by gigantic robotic arms back at the SpaceX Starbase launch tower.
But its experimental upper-stage capsule broke up and fell back to Earth shortly after stage separation.
"Rather than opting to analyze everything for years or decades before any flight tests, as NASA has done, Musk's approach is to build, launch, crash, fix problems, then try again," Zubrin recounted earlier, after touring SpaceX's launch center and its rapidly expanding skunkworks to build Starships, and summiting with SpaceX's supreme commander.
Musk's super-speed assembly and demo flights of prototype Starships - with his Starbase Starfactory now turning out one spacecraft every four weeks - are bringing SpaceX's first robotic and human landings amid the orange-red Martian dunes closer and closer, Zubrin predicts.
Zubrin outlined his latest oracles for the globe's most technologically advanced rocket, and for the Solar System's second potentially habitable planet, during a captivating virtual roundtable with space journalists and Mars aficionados hosted by the Mars Society and Ashton Zeth, the dynamic young anchor of the Society's Red Planet Live webcast.
When I asked Dr. Zubrin about Elon Musk's blueprints to launch a squadron of robots aboard five Mars-bound Starships in 2026, Zubrin forecast the chances of liftoff next year are close to zero.
Musk told his 200 million followers on X, in the twilight days of last summer: "The first Starships to Mars will launch in 2 years when the next Earth-Mars transfer window opens."
"These will be uncrewed to test the reliability of landing intact on Mars," he said. "If those landings go well, then the first crewed flights to Mars will be in 4 years. Flight rate will grow exponentially from there, with the goal of building a self-sustaining city in about 20 years."
Yet Zubrin cautions the projected 2026 blast-off for robotic explorers, and the 2028 launch goal for humans, are both aspirations that are all but unreachable.
"Just speaking as a realist," Dr. Zubrin tells me, there are too many challenges for Musk to overcome during the countdown to the next Earth-Mars orbital transfer window, which opens in November of 2026.
"It's now 2025, and you're talking about launching to Mars in 2026."
"For Starship to go to Mars, you not only have to get Starships on orbit, you've got to get Starship tankers on orbit and perfect orbital refueling."
After lifting off to low Earth orbit, the Mars-bound Starships will have to be loaded with cryogenic methane and oxygen via multiple dockings with SpaceX tankers - while both ships are speeding around the planet at 28,000 kilometers per hour - a complicated operation that has never been tested, he points out.
At the same time, SpaceX will have to perfect the robots that it envisions will help build spacecraft landing pads and human habitats on the Martian surface, prospect for water underground, and convert the water and carbon dioxide captured from the atmosphere into vast reservoirs of super-cooled oxygen and methane for the Starships' return voyage to Earth.
SpaceX's lead engineers for Mars development have outlined these sci-fi-like goals in a series of fascinating conceptual studies, but have never unveiled any of the robot-astronauts that will spearhead these missions.
Dr. Zubrin was the first Mars expeditions strategist ever to propose dispatching an interconnected swarm of advanced robots to prepare a future Martian colony for the humans who would follow - initially in his masterwork, The Case for Mars: The Plan to Settle the Red Planet and Why We Must, and in an ongoing torrent of follow-up books and articles.
"Starship, with its 100-ton capacity, can land a battalion of robots," Zubrin stated in a futuristic feature for the magazine Nautilus.
These could include rovers outfitted with leading-edge cameras, spectrometers and lasers, along with helicopters that could overfly and map the lava tubes that might shelter future habitats.
Robotic photographers could shoot high-resolution images of potential landing sites and base camps for later human astronauts - images that in turn can be transformed into life-like virtual reality simulations that will allow explorers back on Earth to trek through the sites myriad times before touching down on the mysterious ruddy planet.
"Construction robots, too, possibly humanoid in form, could build a Mars base, capable of converting Martian carbon dioxide and water ice into methane-and-oxygen rocket propellant to store in tanks."
"With such a set-up, fully supplied in advance," Zubrin says, "Starships could start sending humans."
During our virtual meet-up, Zubrin tells me that it's almost inconceivable that this robotic army of Mars scouts could be assembled and perfected by the time the next trans-Mars flight path opens 20 months from now.
Yet when the following Hohmann transfer window appears, in late 2028, he projects, "Absolutely, I think that could be done."
"You're talking about developing all this stuff within three years okay, but I think we could do it - I absolutely think we could do it."
"And that should be the goal," Zubrin proposes, "to have a terrific robotic expedition to Mars in 2028."
"Now you say if we did that could we land people in 2031?"
NASA scientists who have charted optimal Earth-Mars flight paths for the next two decades state that the Hohmann orbital window in 2031 opens in January: a flight lifting off from the Earth on January 28, for example, could land on August 6 of 2031.
American and allied astronauts touching down on Mars would mark a sensational leap for the planet's spacefaring civilization.
"It's conceivable we could land people in 2031," Zubrin tells me, but that would depend on the robotic forerunners on Mars completing their essential assignments.
Starship's gargantuan size, with its projected capability to speed one hundred astronauts and 150 tons of cargo - robots, food, oxygen, rovers and satellites - to the Martian dunes is also its greatest drawback, Zubrin says.
Each Starship will land with its propellant tanks depleted, and will depend on being refilled with 600 metric tons of oxygen and methane to make the return odyssey back to Earth.
An automated system to convert Martian H2O and CO2 into these propellants within a year and a half - before the first astronauts land around the robotically built base camp - "would require a power source with an average round-the-clock output of 600 kilowatts," says Zubrin, who holds advanced degrees in aeronautics and in nuclear engineering.
If this propellant production complex depended solely on solar arrays, Zubrin says, the light-collecting panels would stretch out to cover 60,000 square meters, and would weigh about 240 metric tons, which alone would require three Starship launches to transport them to Mars.
Relying on massive solar power systems for this life-and-death project could doom the entire endeavor, Zubrin tells me.
"Forget it."
"You want a nuke - a Mars surface nuclear power reactor," but that would depend on the American government's aid in developing the reactor and approving its use on another planet.
"Space nuclear reactors involve highly enriched uranium," Zubrin says, "which could be used to make weapons and so this is the kind of thing where you've got to get the government involved."
Yet anyone proposing flying American nuclear reactors to power the first astronaut outpost on Mars - who happened to have high-level contacts in the White House - might see quick-fire approval.
Zubrin says while he's been captivated by SpaceX's lightning-speed advances in assembling prototypes of its next-generation Starship rocket and capsule, and its accelerating tests of the Mars spacecraft, he takes issue with Elon Musk's motivation for creating a Mars cosmopolis - filled with one million first-generation Martians - over the course of 10,000 Starship flights.
Musk sketched out his vision of Mars as an off-world sanctuary during a sensational overview he presented last spring at Starbase, when he said: "The overarching goal of the company is to extend life sustainably to another planet - Mars is the only option really - and to do that ideally before World War III."
Building a haven for humans on Mars at breakneck speed is imperative, he said, before "there's something that takes out Earth - like let's say there's a World War III - global thermonuclear warfare."
While predicting that a refuge on the Moon could still be vulnerable during an all-out nuclear clash on Earth, Musk said: "It's way harder to shoot Mars with nuclear."
"Mars would see it coming and probably have some time to stop the inbound missiles."
"Musk has done great things for Mars by creating reusable rockets," Zubrin says, "but his understanding of why we need to go to Mars is off base."
"The reason why we're going to Mars," Dr. Zubrin tells me, is "not to have some survivors after Earth is destroyed, but to create new branches of human civilization that will add their creative powers to humanity a whole."
This will "allow the human race to more effectively deal with all the the challenges that it faces," he adds.
When the human race is spread out across the twin planets, as Mars is terraformed and its ocean and atmosphere restored, Zubrin says, the interconnected Martian and Earth civilizations and scientists will work together to fend off incoming asteroids or comets that threaten either orb, and team up to co-shape a fantastical future for both worlds.