Elon Musk’s SpaceX is working towards making a ‘bleeding’ heavy-metal rocket ship, for which completing a mission might be 100 times as hard as NASA’s most difficult Mars mission,as per one expert.

Recently, director of the Space Technology and Exploration Directorate at NASA Langley, Walt Engelund warned that the design proposed by Elon Musk of his Starship rocket is going to be ‘couple orders of magnitude’ more difficult than any NASA project in history.

This project will be 100 times more difficult than the Curiosity landing, which, as per Engelund ‘is arguably one of the hardest things we’ve ever done at NASA.’ “It won’t be easy for us or SpaceX,” Engelund told Business Insider.

Musk previously hinted at prominent changes to the Starship launch system for the rocket to Mars that could help ‘cheapen’ flight costs and maybe change the way space travel is seen. One of these changes is including using a stainless steel alloy instead of traditional carbon-fiber materials.

Elon Musk shows off ‘Starship’ rocket for taking humans to Mars

But, the more challenging and surprising plan is to create a spaceship that will ‘bleed’ rocket fuel to help it cool off and avoid burning up in both Earth and Mars’ atmospheres, keeping the entire vehicle cool. Engelund’s primary concern is Musk’s plan of making the ‘bleeding’ heavy-metal rocket ship, posing question on what would happen if some pores get clogged.

“I’ve seen instances where you’ll get one clogged channel… and it will immediately result in burn-throughs,” Engelund said while talking to the publication. “A model will disappear in a hypersonic wind tunnel. It almost vaporizes, there’s so much energy and so much heat.”

However, Engelund also acknowledged that SpaceX is indeed bringing unprecedented energy and creativity to the private space industry, and also envisions further collaboration between NASA and SpaceX, wrote Futurism.

“They’ve surprised a lot of people, and have a lot of smart people working for them, and Elon seems to be really committed and dedicated to this,” Engelund told Business Insider. “Perhaps there are some things that we could do with them. I suspect there will be.”