SpaceX, an aerospace company founded by Elon Mus, is working diligently on a wildly ambitious project: permanently populate people on Mars.
In order to make this vision a reality, Muska Company is developing a colossal, fully reusable launch system called Starship.
Star ship is supposed to be a 180-foot spacecraft that will ride in orbit at the top of the Super Heavy, rocket amplifier, about 220 feet high, according to the latest Mask descriptions. The spacecraft is designed for refueling in a low Earth orbit in order to launch 100 passengers in Mars and more than 100 tons of cargo.
But the success or failure of the launch system ̵
One change involves construction Spacecraft of Alloys of Stainless Steel instead of carbon composites. But the surprising shift, according to experts in the aerospace industry, is how Star Ship tries to keep itself from burning in the atmosphere of Mars and Earth.
Instead of relying on thousands of heavy ceramic tiles to protect Starship from heat, as NASA did with its spacecraft, Musk says the spacecraft "pumps" rocket fuel through tiny pores to cool. Theoretically, putting a fluid between Starship's steel skin and a burning hot plasma, which is generated when it is spilled through atmospheric gases, prevents the vessel from collapse.
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But can SpaceX extract a launch system of this unprecedented size and design, says Walt Engelund, an aerospace engineer and Director of the Space Technology and Research Directorate of NASA Langley.
"A large-scale entry, descent, and landing is what NASA called for a decade. We spent a lot of time and paid a lot of attention to how we can do it on Mars," Engelund said. Business Insider. "We landed on the metric point of the Curiosity rover – this is the greatest thing that we have ever laid on the surface of Mars."
To move from the Martian landing of a car-sized robot to a ship sized to a building filled with people, Engelund said it's "a couple of orders" – about 100 times – more difficult than landing the curiosity that he said "this is one of the hardest things we have ever done to NASA. "
"It will not be easy for us or SpaceX," Engelund said.
Why the Star Ship Becomes Heavy Metal Rocket Ship
Musk believes that he can build a self-sufficient city on the red planet 2050 . He wants individual tickets to Mars to be as cheap as a house on Earth, and for return trips – for free.
The Starship-Super Heavy launching system is the way Musk plans to achieve this, and he said that the transition to of stainless steel alloys is a way to reduce costs and build the system faster.
"A star ship will look like liquid silver," Musk said of the change in December, adding that the ship would have a polished surface to repel heat – a literal case of a cool factor.
In an interview with popular mechanics, Musk explained that steel is about 67 times cheaper than lightweight but extremely strong carbon fiber composites, which SpaceX plans to use in September. Steel is also easier to operate than carbon fiber, allows faster prototyping, and gets better than intense heat.
Moreover, according to Mus, the strength of the steel "is increased by 50%" when it touches ultracold liquids, including cryogenic methane and oxygen, which the Star Ship can use to move through space.
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The problem with steel, however, is that the material is tight and heavy. At the very least, one earlier version of the General Dynamics "Atlas", which was made of metal, is under its own weight in the start-up panel.
However, Musk suggested that the use of steel in SpaceX would be very different and would make the Starship transformed stronger, more durable and less difficult. Ultimately, he says, significant changes will improve the performance of the missile ship over the old design.
"I'm sure the stainless steel ship will be lighter than the advanced aluminum or carbon fiber, through strength to weight against temperature and reduce the need for heat protection," Musk said in January.
But, just as rigid as steel, it is not invincible, especially when it forms the skin of a spacecraft screaming through atmospheric gases.
Sweating and bleeding for survival
A star ship could penetrate the atmosphere of Mars and Earth 19000 km / h . At such speeds, as Musk said, parts of a ship propeller, such as a nose, could have been exposed to a temperature of about 2700 degrees Fahrenheit.
Enough heat to destroy the steel alloy that Musk said that SpaceX can use for the outer skin of Starship. The material, which is called 310S, is often exposed as a heat-resistant metal, since it has a lot of mixed chromium and nickel. (This does not look like steel used in kitchen utensils and pots.) But steel 310S nonetheless begins to react with oxygen and roasts about 2000 degrees and melts in about 2400.
Rocket the ship needs protection from intense heat, therefore, Mus's plans call the body of the Star ship to cool itself using liquid fuel during landing.
Musk said "Popular Mechanics" that he decided to abandon thermal tiles, similar to the space shuttle, in order to preserve weight and avoid the risk of damage or loss of tile.
Read more : This NASA astronaut tried a new spacecraft SpaceX and Boeing – that's what she thinks
Instead, he explained, Star ship "bleed" or rocket fuel from tiny holes in its steel skin, and that the liquid layer will carry with it the burning heat of the atmospheric entrance.
"On the windy side, what I want to do is the world's first regenerative thermal shield." The double-edged stainless steel shell is like a stainless steel sandwich, "Mask said. "You pass either fuel or water between the sandwich layer and then you have micro perforations on the outside – very small perforations – and you essentially bleed the water, or you could bleed the fuel through a micro perforation on the outside. he will see them if you do not come.
He added that the thermal shield would make a double bond with the strengthening of the stellar body of the Star ship.
"As far as I know, this has never been offered before," Mask said. 19659002] Experts told Business Insider that Musk is correct that no space to The aircraft did not go into orbit and did not return to Earth with such a thermal shield, but the concept of sweating or "transpirational" thermal protection is not new, and it has a history of an extremely complicated technical task.
Transpirational cooling for men-months and ICBMs  Musk says the space shuttle launcher will be polished to mirror finish. © Kimi Talvitie
Active "cooling" has existed for millions of years as a skin of mammals. When the temperature of the human body rises too high, for example, microscopic pores supplant sweat. This liquid then evaporates to avoid excess heat and prevent overheating. As for spacecraft for sweating, NASA began playing with a naturally-cooled cooling system before landing astronauts on the moon.
"The idea of cool cooling is not new. It's been a decade," Engelund said. One patent filed by NASA in 1965 suggested the use of urine for astronauts to cool the thermal shield at the bottom of the space capsule. In 2006, the space agency spent at least $ 70,000 on researching an inflatable, heat-shielded transpiration that could help a land-based spacecraft on Mars.
"Sweeping" spacecraft also played a role in the Cold War race. In March 1976, the US Department of Defense conducted a test-release of a cooled transpiration tip for vehicles. Such vehicles return to space on intercontinental ballistic missiles, return to the Earth's atmosphere thousands of kilometers per hour and strike nuclear warheads.
However, according to historic US Air Force documents, the project was canceled later in the 1970s due to limited funding and "design problems that were detrimental to development." Instead, engineers chose simpler "ablative" thermal shields that isolate the vehicle by burning them on a re-entry. Information about problems encountered with protective transpirational thermal shields is mainly classified. But George Herbert, an aerospace engineer who explored the military use of space launch vehicles, told Business Insider in an e-mail message that "Issues reported and known include blocked holes in transpiration." In other words, a challenge that usually encounters teenage skin: clogged pores.
"What to do if a bird spoils your rocket?"
Several experts reported that they were interested in the problem of blocking the design of the heat shield Zorya.
"You can imagine that you do not need much to kill something like this if they were microscopic pores," Engelund said.
Dwayne Day, who helped investigate the loss of NASA's space shuttle with Columbia and its crew, imagined one unexpected scenario with which a star ship would collide anywhere on Earth launch.
"What should I do if a bird clogs your rocket and he will close several holes, and then, when this thing comes back, no coolant does not come out of these holes and this part of the car overheats?" The day was e-mailed to Business Insider.
Engelund said that he had seen problems with clogged cooling systems in tests performed on NASA hypersonic aerodynamic tunnels. During such experiments, large-scale vehicle models that can explode the air thousands of kilometers per hour to learn how they perform are entering the tunnel. Some of the tests are running included heat shields that pump fluid through the channels only under the model skin to cool it, but not all models survived.
"I've seen cases when you get one dead channel … and it will immediately burn," Engelund said. "The model will disappear in a hypersonic aerodynamic tube, it's almost evaporating, it has so much energy and so much heat."
Musk said that the use of methane as a coolant may be better than water.
"Rapid evaporation of water can withstand the intuitive cause of its freezing and blocking of cooling channels," he said .
But Englund also sees problems with methane. Under the influence of high temperatures, carbon atoms in hydrocarbon fuels (for example, methane) can be "cooled" or glued and converted into solids. Such fragments can then block small structures, such as pores.
"I would be very concerned about this," Engelund said, adding that one more major concern would be the impurities in the fuel, which could also lead to slaughter.
One of the possible ways to solve these issues, according to Engelund, may simply be to add more time than it seems necessary, "only if a small percentage of perforations is clogged, or channels flowing through the coolant to these perforations."
In addition to issues such as bird droppings and clogging, there is a fine dust that blows through Mars. It can get into the pores coming from the fuel, and it may be difficult to find and remove those blockages while staying on the red planet.
"Inspection and certification, in general, would be an issue of concern for such a large-scale active system – especially on Mars, where you do not have access to large goats or towers to climb and check," Engelund said. "I think you could
May the star ship take heat?
Musk shared only pieces of the latest design of a star ship and did not introduce a complete picture to the public as he did in the past. (Visualizations shown in this story are lovingly Kimi Talvitie 3D artist.
But Musk said in December that he "would provide detailed explanations in March / April" In anticipation of the successful launch of the prototype "test-hopper" that the company is building in Texas.
Read more : Giant rocket ship SpaceX was damaged by powerful winds in Texas – the nose end was blown up, and Elon Musk said that the repair would take a week
Meanwhile, Musk shared a video (above) that appears to show metal testing Thermal Screen for Starship. It is still unclear how many SpaceX studies performed the concept of transpirational cooling.
"A huge risk if they did not work to qualify and test what they want to do," said Herbert. "But if they did, it could become the real winner for the new design."
If this does not work, Engelund said, this is not necessarily a dead end to the Mask spacecraft.
"He may find that this is not, or too expensive for certification or testing, and he may find a better idea," Engelund said. "He was very good at his career."
SpaceX also expects constant adjustments and changes as engineers are working to make Starship a reality.
"We use the same fast iteration in the design approach, which has succeeded in the programs Falcon 1, Falcon 9, Falcon Heavy and Dragon," – said the representative of Business Insider by e-mail, turning to the company rocket-spacecraft.
But SpaceX rejects any comparison between a spaceship and a NASA ship.
"Curiosity advanced the limits of Mars technology [entry, descent, and landing] of the 1970s, including a parachute-based EDL architecture," SpaceX said. "We adopt a completely different approach, using what we did with Falcon 9, and we have ample opportunity to demonstrate it on Earth before flying to Mars."
Despite the high barriers SpaceX faces in its quest to launch and land on Mars, no expert with whom we spoke, did not say that the SpaceX system was unlikely.
"They surprised a lot of people, and many smart people work for them, and Elon seems to be truly devoted to this," Engelund said. "There may be some things we could do with them. I suspect it will be."