(CNN) – The explosion of a SpaceX Starship vehicle during regular ground testing on Wednesday sent a shockwave of fire and smoke that appeared to engulf the company’s testing facility in Starbase, Texas. Mishap has questioned the company’s ability to hash the key design and engineering challenges of vehicles that are considered important to SpaceX’s founding goal of ultimately transporting a fleet of people to Mars.
SpaceX CEO Elon Musk spoke to a South Texas employee in late May, aiming to once again support Mars’ ambitions, he highlighted the metrics that measure success.
Later in his speech – Musk gave two days after the recently released Starship Prototype failed at re-entry. The roadmap rests on certain deadlines determined by laws of physics, thanks to how far Earth is from the red planet.
The distance between Earth and Mars ranges from approximately 35 million to 250 million miles (56 million to 400 million kilometers) depending on where each planet is in its orbital path around the Sun. To save time and fuel costs, the mission aimed at visiting Red Planet will have to wait until it is an ideal point compared to Earth. This is a major alignment opportunity, also known as the “Martian moving window,” which occurs approximately every 26 months over a few weeks.
The next window, where travel time to Mars will be reduced from over a year to just six to nine months, will be coming into the second half of 2026. The Musk’s roadmap suggests SpaceX wants to send up to five non-white partial spacecraft cars loaded with cargo on Mars in the meantime. However, there are some major concerns SpaceX needs to address before its first cargo ship is set up on Red Planet, and Wednesday’s explosion (the fourth Starship so far this year) may be evidence of that.
Musk spoke about the possibility of reaching Mars in 2026, and said during his speech in May that he imagined that “50/50 Chance” could win a spacecraft spacecraft on Mars next year.
Before the 2026 Mars Movement Window opens, SpaceX will be debuting another upgraded version of Starship Spacecraft and Super Heavy Rocket Booster.
With the new spacecraft system, both the first stage booster and upper stage ship are slightly larger, allowing together to carry 661,387 pounds (300 metric tons) of propellant.
This is a substantial upgrade similar to one SpaceX version 2, which debuted earlier this year, adding 25% propellant capacity compared to previous test flight models.
SpaceX is struggling to run version 2 as expected. The first two test flights, which took place in January and March, each failed minutes after takeoff, causing rain to fall near a population-based island in eastern Florida.
The final test flight in May flew further during the flight, but the spacecraft lost control before re-entrying, leading to a nailed, uncontrolled descent into the Indian Ocean.
And Wednesday’s explosion during routine ground testing raises even more concerns about how long SpaceX will take to fine-tune Starship designs and ensure that cargo and humans can safely transport. The company has not disclosed how much of a set-up it will be for the vehicle or its launch facilities.
Preliminary data suggested that the explosion was caused by the detonated gas tank, Musk said in a social media post. The tank “has fallen below proof pressure,” he said. That is, they suggested that previous stress tests and known characteristics of tanks should have survived the scenario. This is a potentially unique problem that has never been observed before.
During his speech on May 29, Musk emphasized that introducing more upgrades and further increasing the size of the spacecraft is essential for long-term success.
“It requires three major iterations of key new technologies. To make it work really well,” Musk told employees during the spacecraft update.
Musk said he hopes the updated spaceship will make its flight debut by the end of the year.
However, even if the new version pulls out an untouched test flight along the same suborbital pathway that SpaceX conducted its previous Starship test mission, it does not guarantee that the vehicle is ready for an interplanetary excursion.
That’s because even with the added fuel capacity, the spacecraft must be rounded out with more propellant after reaching space for a long trip to Mars.
SpaceX plans to do this by firing a series of tankers, or a spacecraft vehicle designed to carry batches of fuel and oxidant. These tankers are idle in Earth’s orbit, simmering along with the spacecraft, moving thousands of pounds of propellant, supplying the vehicle with the fuel it needs to continue its deeper journey through the solar system.
In particular, it has never been done before to move fuel between two vehicles in space.
“We’ve never done that. Nobody did it — autonomously transferring fuel from one spacecraft to another,” said Bruce Jakoski, professor emeritus of geology at the University of Colorado Boulder University Research Institute for Atmospheric and Astrophysics.
“That’s difficult,” Jakoski added, taking into account that oxygen and methane are essentially kept at temperature, especially considering spacecraft vehicles running on estuary fuel. Also, in orbital microgravity environments, the fuel may float in a tank rather than settling in one location. So, amid countless other technical difficulties, SpaceX probably needs to devise a pump or motor that can effectively inject fuel from one vessel to another.
At present, it is not even clear how many tankers SpaceX needs to fire to provide enough gas to one spacecraft vehicle for a trip to Mars. (Previous estimates NASA staff and third-party experts predicted that around a dozen spacecraft tankers could be needed for a lunar mission.)
In his speech, Musk said he believes that fuel transfer within the space is “technically feasible.”
SpaceX will not attempt to conduct its first tanker flight test by next year, Musk added.
Even after SpaceX sorts out the issue of propellant transfer, they will face another important technical question: How will Starship survive a trip to the surface of Mars?
Musk was called the issue “one of the hardest problems to solve last month.”
“It’s extremely difficult to do that because no one has really developed a reusable orbital heat shield,” he said. “This will be something we’ve been working on for several years to continue honing.”
Vehicles that need to safely land on the planet’s body while traveling at orbital speed require a component called a heat shield. This is a special coating on the outside of the vehicle that acts as a buffer to modhing temperatures produced by processes entering the planet’s atmosphere.
On Mars, one of the key issues is air. It is almost entirely made up of carbon dioxide.
When a spacecraft hits Mars’ atmosphere, it compresses the air in front of it violently, creating a burning temperature. And the conditions for re-entry are so intense that this process literally tears electrons from atoms, breaks down molecules, and turns carbon dioxide into carbon and oxygen.
A re-entry into Mars actually produces more heat–Musk suppresses oxygen, which destroys the shield than the process of returning to Earth. Starship’s heat shield ultimately needs to be durable enough to survive potentially multiple re-entry of both types.
The chances are likely to be small to solve all the technical difficulties required for SpaceX to send a cargo-filled spacecraft to Mars at the end of next year, but even bigger problems need to be solved.
For example, if SpaceX wants to send humans to Red Planet, the company must find a way to ensure that Starship’s appearance can keep people safe from the deadly radiation that showers through the six-month journey. You should have a life support system that is fully equipped with breathable air.
As Musk said, we need to explain the needs of all humans. “You can’t overlook it, just like it’s the equivalent of vitamin C,” he said.
Once the spacecraft’s vehicle reaches its destination, it will likely need to refill the fuel at a Mars depot before returning home.
As Musk said in a previous social media post, the idea that there will be enough infrastructure on Mars by 2029 or 2031 makes it strange to allow such crew missions.
Still, industry experts say SpaceX’s bold ambitions spark both excitement and skepticism.
“I’m a fan of what SpaceX is trying to do. I’m fully subscribed to this vision of a multifaceted society,” said Olivier de Weck, professor of astronauts and engineering systems at the Massachusetts Institute of Technology. “But that’s logistics first and foremost. And what I lack is my thoughts on cycling, fuel production and return to Earth.”
However, Phil Metzger, a planetary physicist at the Florida Space Institute, stressed that SpaceX tends to fulfill its promises, even if it’s a few years behind.
“They feel bad for some of them (the test flight obstacles on the spacecraft). “Given their design and development philosophy, I think they’re still in the window of expected results.”
But Metzger added, “We’ve reached the point where you start to worry.”
Sign up for CNN’s Wonder Theory Science Newsletter. Explore the universe with news about fascinating discoveries, scientific advances and more.
