A fiery explosion of a SpaceX rocket has raised doubts over owner Elon Musk’s ambitious goal of reaching Mars by 2026.

On Thursday, while preparing for the tenth flight test of its interplanetary Starship project, SpaceX witnessed its Starship 36 vessel burst into flames at its launchpad.

The company explained that despite completing a limited engine test earlier in the week, preparations for a wider engine test were interrupted by a “sudden energetic event” which resulted in “the complete loss of Starship and damage to the immediate area surrounding the stand”.

According to Musk, the “preliminary data” suggested a pressurised tank – known as a ‘composite overwrapped pressure vessel’ or COPV – inside a cargo-holding section of the spacecraft “failed” below its intended maximum pressure threshold.

“If further investigation confirms that this is what happened, it is the first time ever for this design,” said Musk.

Despite causing a loud rumble and reportedly startling nearby residents, SpaceX reported no injuries or hazards to surrounding communities in Texas, USA.

Quite the trek to Mars

Before the explosion, SpaceX announced plans to launch its first unmanned Starship vehicles to Mars by 2026.

“These first vehicles will gather critical data on entry and landing, serving as the forerunners to future crew and cargo deliveries to the Martian surface,” read SpaceX’s website.

While the Moon averages 384,400 kilometres from Earth, Mars averages a significantly lengthier 225 million kilometres, with the minimum theoretical distance being 54.6 million kilometres depending on the orbits and positions of the planets.

Most of the time Mars is simply out of reach, leaving space travel reliant on ‘transfer windows’ when the Red Planet is at its closest to Earth.

Adam Gilmour, co-founder and chief executive of Australian space company Gilmour Space Technologies, explained such opportunities occur roughly every two years.

“Since the Earth rotates faster than Mars, it ends up taking two years for them to come close together, and then another two years after that,” Gilmour told Information Age.

“On either side of the window there’s times you can still go — I’m guessing about four to six weeks on either side of the optimal window — but you need a lot more energy.”

He added that rather than making a beeline to Mars, these transfer windows typically use the ‘Hohmann transfer’, a method that utilises an elliptical orbit for travel and times the rocket launch to intercept Mars at a fuel-efficient point during the planet’s journey around the sun.

“By a year later, Mars is on [the opposite side] of the Sun to Earth,” said Gilmour.

“You’d essentially need some sort of warp drive technology to get over there.”

Tonnes to do

Space travel, Gilmour explained, is dictated by data gathering and vehicle tests which are “much riskier” than their on-the-ground counterparts.

Indeed, SpaceX’s latest “loss of Starship” is but one in a string of fiery explosions, with Musk writing the incident off as “just a scratch”.

Still, Gilmour said Musk and his company need to “get a lot of the tech done and dusted” before attempting to reach Mars, including the achievement of an unprecedented mid-orbit fuel transfer which would involve launching multiple Starships into space and using them to fuel up the one bound for Mars.

Although Starship recently achieved a historical water landing and two return tower catches, Gilmour also pointed out the need to perform successful ground landing on Earth.

“You can’t water land on Mars, so you’ve got to test a similar landing here on Earth,” he said.

“If you’ve checked off a successful landing and a fuel transfer, those would be the two absolute bare minimum checks before you can say ‘I’m going to go all the way to Mars’.”

Musk has further lamented the challenge of getting Starship to the surface in one piece – Mars’ atmosphere is much thinner and colder than Earth’s, but it can still cause problems for heat shields.

“No one has ever developed a truly reusable orbital heat shield – that is extremely difficult to do,” he said last month.

“This will be something that we’ll be working on for a few years, I think.”

Gilmour added Starship’s latest explosion didn’t indicate a notable safety issue – standard practice in the sector is to adopt exclusion zones which ensure humans are many kilometres away from fuelled rockets – but the company may need to take stock of its recent complications.

“They've had quite a few failures in a row, and I wouldn't be surprised if they take a pause now and just say ‘look, let's do a full review of the rocket for the next four to six months to stop all the failures,” said Gilmour.

“I think he’s going to struggle to get the 2026 window.

“More realistic is 2028 or 2030, and that would still be unbelievably awesome for the first Mars mission.”

SpaceX did not respond prior to publication when asked if it would readjust its plan to reach Mars by 2026.