Elon Musk plans to launch a prototype of the car soon, which may change the rules of space travel. As we all know, the interstellar spacecraft will be a completely reusable transportation system that can carry up to 1
The founding spirit of Elon Musk’s private space company SpaceX is to make life more planetary. This is partly caused by existential threats such as asteroid collisions, which are enough to wipe out humans.
Placing other planets will put some eggs in other baskets, and if one of them is going to experience a catastrophe, this will save human civilization.
He said that in 2016, the entrepreneur outlined his rationale at an international conference in Mexico: “History will diverge in two directions. One path is that we will stay on earth forever, and then we will eventually become extinct. “
“The alternative is to become a space civilization and a multi-planetary species. I hope you agree that this is the right approach.”
Musk often talks about his dream of building a city on Mars. He believes that settlements need a large number of people to be self-sufficient.
To realize this dream, you need a vehicle that can do the job. The interstellar spacecraft is a combination of rockets and spacecraft, which can transport more than 100 people to the red planet at a time.
The system is designed to be completely reusable, which means that the main hardware elements will not be discarded or burned in the sea like some other launch systems, but will be recovered from space. It can then be refurbished and flown again, thereby reducing the cost of the entire enterprise.
The rocket part of the system is called super heavy, and the spacecraft part is called a starship.
The combined system will be up to 120m (394 feet) high and is also called a “starship”.
Let’s take the spaceship first. This stainless steel car has a nose cone and landing fin, similar to a rocket ship from the golden age of science fiction.
This 50 m (160 ft) long spacecraft, also known as the upper platform, has a huge payload bay near the front, which can tow large cargo or people to a deep space destination.
In the middle of the propeller is a propellant tank. These supply liquid methane (CH4) and liquid oxygen (O2) to the six Raptor engines at the rear of the vehicle.
Methane is a fuel, and oxygen acts as an oxidizer-a chemical substance that burns fuel. This combination is called methotrexate.
The choice of fuel is unusual for a rocket engine, but methane produces a lot of thrust. Considering Musk’s design on Mars, this is also a prudent choice. The founder of SpaceX said that a chemical process called the Sabatier reaction can be used to synthesize CH4 from the groundwater of Mars and carbon dioxide (CO2) in the atmosphere.
SpaceX has spent more than ten years developing an efficient Raptor engine. Combustion is carried out in stages, and the engine is designed to reduce wasted propellant.
Using Martian resources to refuel the interstellar spacecraft to return to Earth will give a certain degree of self-sufficiency, making the journey more feasible and cost-effective.
Now, let us turn to the Rockets. The Super Heavy is 70m (230 feet) long and will be filled with 3,400 tons (6.8 million pounds) of low-temperature (refrigerated) naphthalene.
It will be powered by about 28 Raptor engines (this specification has been changed many times), and can provide a maximum thrust of about 16 million pounds (72 meganewtons). It should be able to lift a payload of at least 100 tons (possibly as much as 150 tons) into low Earth orbit.
This will make Super Heavy more powerful than the huge Saturn V launchers used in the Apollo moon missions in the 1960s and 70s.
How does it get into space?
When it rises from the launch pad, the combined starship system will begin to tilt toward a predetermined orbit.
When the high altitude is separated in space, the super-heavy aircraft will flip and fall towards the earth.
When descending, Super Heavy will deploy a steel structure called “grid fin” from the side of the booster, which is shaped like a potato waffle. These will help guide the rocket stage back to its launch pad so that it can land and fly again.
Previously, SpaceX wanted to ignite the Super Heavy’s Raptor engine to guide it to a precise landing site with six steel legs. SpaceX did a similar thing in the first phase of its Falcon 9 rocket, landing it safely on landing pads and drones after launch.
But Mr. Musk recently tweeted that this thinking has changed. SpaceX now plans to use an arm on the launch tower to grab the descending booster.
This structure allows engineers and crews to approach the spacecraft and rockets while sitting on the mat before launch. However, it remains to be seen how this “capture mechanism” will work.
At the same time, the upper level of the interstellar spacecraft can be inserted into the “parking track” after separation to refuel it.
“If you just fly [Starship] Going into orbit without any replenishment is very good-you will send 150 tons to low earth orbit and no fuel can flow anywhere else,” Musk explained in the keynote speech at the 2017 conference.
“If you transport the tanker and refill the track, you can fill the tank all the way to the top and get 150 tons [of payload] All the way to Mars. “
In order to refuel, the spacecraft will be docked or paired with another spacecraft that has orbited the earth, which will only act as a propellant storage.
Musk said in 2017: “The two ships will actually mate in the rear. They will use the same mating interface that they connect to the booster when they lift off.”
“To transfer the propellant, it is very simple: you can use the control thruster to accelerate in the direction you want to empty.”
What will the interstellar spacecraft be used for?
For long-distance travel to and from Mars (one-way may take up to 9 months), Musk hopes to install about 40 passenger cabins in the payload area near the front of the upper deck.
“If you really want to crowd people, you can imagine that there are five to six people in each cabin. But I think that in most cases, we want to see two or three people in each cabin, so every flight to Mars There are about 100 people in name,” Musk said.
The payload bay will also house public areas, storage spaces, kitchens and shelters where people can gather to withstand the solar storms, during which the sun brings harmful charged particles into space.
The interstellar spacecraft may also play a role in NASA’s Artemis program, which aims to establish a long-term human presence on the moon. In 2020, NASA awarded SpaceX US$135 million to advance the design of an “interplanetary spacecraft” for use as a manned lunar lander.
The version tailored for Artemis flights will not have the heat shields or flaps needed to return to Earth. Instead, the Interstellar Spacecraft Human Landing System will remain in space after its initial launch from the Earth and will be used for multiple trips between the lunar orbit and the lunar surface.
The unloaded or loaded version of the interstellar spacecraft has a payload bay that opens like a crocodile mouth. This will make it available for launching satellites. SpaceX said the huge payload capacity opens up possibilities for new robotic science missions, including telescopes larger than the James Webb Observatory, which is the upcoming successor to Hubble.
The system can even be used for high-speed travel between different destinations on the earth.
Musk said that “interstellar spacecraft” could eventually transport people to destinations in the “larger solar system,” including gas giants such as Jupiter. But this is still a long-term goal.
How do the upper floors land?
In order to bring other spacecraft back to Earth, engineers rely on parachutes or designed aircraft so that they can land on the runway.
But the upper stage of the interstellar spacecraft took a different approach. When preparing to land, the ship first re-entered the atmosphere at a 60-degree angle, and then “belted” to the ground in a horizontal position.
This way of returning completely relies on the atmosphere to slow down the vehicle’s descent speed. The disadvantage is that in this configuration, Starship is inherently unstable.
Therefore, the vehicle uses four steel landing flaps, which are located at the front and rear of the vehicle to control its descent. It’s like a skydiver using his arms and legs to control a free fall.
“This is completely different from anything else… we are falling under control,” Elon Musk said in the 2019 spacecraft update.
“You are trying to create drag instead of lift-actually the opposite of an airplane.”
When the “starship” approaches the ground, its speed should be slow enough to burn the engine, thereby turning the vehicle into a vertical position. It then uses the Raptor as a retro rocket to guide the vehicle to a safe landing.
Musk said that this general method can be used to safely land a starship on any planetary surface in the solar system (including Mars).
When to fly?
In the past few years, SpaceX has tested various prototypes of the upper stage of the Starship at its Boca Chica facility in Texas.
The company started with a 39 million tall “test article” called “Starhopper,” which has similarities to the water tower. Since flying this aircraft to 150 meters above the ground, SpaceX has been developing increasingly complex Starship prototypes.
In December 2020, SpaceX launched a test article called SN8 (Spacecraft 8), which is the first article with a nose cone and flaps. After reaching an altitude of 12.5 kilometers, the abdomen of SN8 suddenly turned back to Earth, providing SpaceX with valuable engineering data about the final part of the spacecraft’s return from space.
It was almost a flight from a textbook, but the vehicle approached the landing pad at too fast and too hard, causing it to fall and explode. SpaceX has moved the prototype SN9 to the launch pad, and this time, their goal is to keep landing.
Elon Musk said in October 2020 that SpaceX’s goal is to launch an interstellar spacecraft on an unmanned aircraft to Mars in 2024.
Some observers pointed out that Musk’s timetable is sometimes optimistic. However, no matter how ambitious he is, he has built a reputation for finally achieving his goals.
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