Elon Musk plans to soon launch the prototype of a vehicle that could be a game changer for space travel. Starship, as it is known, will be a completely reusable transportation system that can transport up to 100 people to the Red Planet.
The founding of Elon Musk’s private space company SpaceX was to make life multi-planetary. It is motivated in part by existential threats such as an asteroid collision large enough to wipe out humanity.
By establishing other planets, some of the eggs would be placed in other baskets, which would save human civilization if one of them experienced a disaster.
In 2016, the entrepreneur set out his rationale at an international conference in Mexico: “History is going to split in two directions. One way is that we will stay on earth forever, and then there will be an eventual extinction event,” he said. he said.
“The alternative is to become a spatial civilization and a multi-planet species, which I hope you will agree to be the right way.”
Musk has often talked about his dream of building cities on Mars. He believes that settlements need a large number of people to become self-sufficient.
To realize this dream, you need a vehicle that fulfills the task. Starship is a rocket and spacecraft combination that 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 most important hardware elements are not thrown away in the sea or allowed to burn up, as happens with other launch systems, but are recycled into space. They can then be refurbished and flown again, reducing the cost of the entire business.
Starship: an overview
The rocket part of the system is called Super Heavy, while the spacecraft part is called Starship.
The combined system will be 120 meters high and is also called Starship.
Let’s take the spacecraft first. The stainless steel vehicle with its nose and landing fins looks like the rockets of the golden age of science fiction.
The 50 m long vessel, also known as the top floor, has a large cargo space near the front that can transport large cargo or people to destinations in the deep space.
In the center of the vessel are the propellant tanks. This feeds liquid methane (CH4) and liquid oxygen (O2) to six Raptor engines at the rear of the vehicle.
Methane is the fuel and oxygen acts as an oxidizing agent – a chemical that causes the fuel to burn. The combination is called metaloks.
The choice of fuel is unusual for rocket engines, but methane can cause a lot of thrust. It is also a wise choice in light of Musk’s designs on Mars. The founder of SpaceX says that CH4 can be synthesized from Martian groundwater and from atmospheric carbon dioxide (CO2) through a chemical process called the Sabatier reaction.
SpaceX has spent more than a decade running the highly efficient Raptor engine. The combustion takes place in phases, and the design of the engine cuts the amount of fuel wasted.
Refueling your Starship for the return trip to Earth using Mars resources will provide a degree of self-sufficiency, which will make travel more feasible and cost-effective.
Let’s turn to the rocket now. Super Heavy, which is 70 meters long, will be filled with 3,400 tons (6.8 million pounds) of cryogenic (refrigerated) metal ox.
It will be powered by about 28 Raptor engines (this specification has changed several times already), offering about 16 million lbs (72 Meganewtons) of maximum thrust. It must be able to lift at least 100 tons of payload, and possibly as much as 150 tons, to a low earth orbit.
This will make Super Heavy more powerful than the huge Saturn V launcher used for the Apollo Moon missions in the 1960s and 70s.
How does it get into space?
As it ascends from the launching platform, the combined Starship system will begin to rotate towards the intended trajectory.
When the upper stage separates into space, Super Heavy turns around as it falls back to Earth.
As it decreases, Super Heavy steel structures, called ‘grid fins’, shaped like potato waffles, will use from the sides of the booster. This will help send the rocket stage back to its launch pad so that it can be flown again.
Previously, SpaceX wanted to set Super Heavy’s Raptor engines on fire to lead it to a precise landing on six steel legs. SpaceX does something similar with the first phases of its Falcon 9 rockets, landing them safely on landing pads and drunken ships after a launch.
But Mr. Musk recently tweeted to say that this thinking has changed. SpaceX now plans to catch the descending booster using an arm on the launch tower.
It is the structure that gives engineers and crew members access to the spacecraft and rocket as they sit on the road before launch. Exactly how this ‘capture mechanism’ will work remains to be seen.
Meanwhile, the Starship upper stage can be placed in a “parking lot” after separation, so that it can be refueled.
‘If you just fly [Starship] to spin and not refill, it’s pretty good – you’ll get 150 tons on a low Earth orbit, and you have no fuel to go anywhere else, “Musk said during a speech on the conference in 2017 explained.
‘If you send up tankers and refill a orbit, you can refill the tanks to the top, and get 150 tons [of payload] all the way to Mars. ‘
To refuel the spacecraft, the spacecraft would come together or mate with another Starship – already revolving around the Earth – which only serves as a fuel depot.
“The two ships will actually share at the rear. They will use the same mating interface as they used to connect the booster during the lift,” Musk said in 2017.
“Transferring propellant becomes very simple: you use steering propellers to accelerate in the direction you want to empty.”
What will Starship be used for?
For long-distance travel to Mars and back – which can take up to nine months each way – Musk wants to install about 40 cabins in the cargo area near the front top stage.
“You could possibly have five or six people per cabin, if you really want to crowd people. But I think most of the time we would expect to see two or three people per cabin, and therefore about 100 people per flight to Mars,” Musk said. . said.
The cargo hold would also house common areas, storage space, a kitchen and a shelter where people could gather to protect against solar storms, where the sun eliminates harmful charged particles in space.
Starship could also play a role in Nasa’s Artemis program, which aims to establish a long-lasting human presence on the Moon. In 2020, SpaceX was awarded $ 135 million to NX to advance the design of Starship so that it could be used as a lunar lander with crew.
The version adapted for Artemis flights does not contain the heat shield or valves needed for a return trip to Earth. Instead, the Starship Human Landing System would remain in space after its initial launch from Earth, to be used for multiple journeys between the lunar orbit and the lunar surface.
The unmade or cargo version of Starship contains a boot that opens like the mouth of a crocodile. This will make it possible to use satellites. According to SpaceX, the large payload provides opportunities for new types of robotic science missions, including telescopes larger than the James Webb Observatory – the successor to Hubble.
The system can even be used for fast travel between different destinations on earth.
Musk says Starship could eventually transport people to destinations in the ‘larger solar system’, including gas giants like Jupiter. But it remains a long-term goal.
How does the top stage land?
To bring other spacecraft back to Earth, engineers relied on parachutes, or designed the vehicle so that it could land on a runway.
But the upper stage of the Starship follows a different approach. When ready to land, the ship re-enters the atmosphere at a 60-degree angle and then “belly-flops” in the horizontal position to the ground.
This way of returning relies entirely on the atmosphere to slow down the vehicle’s descent. The downside is that, in this setup, Starship is inherently unstable.
The vehicle therefore uses four steel landing flaps, located near the front and rear of the vehicle, to control the descent. It’s just like a parachutist using their arms and legs to control a free fall.
“It’s completely different from anything else … we’re doing a controlled fall,” Elon Musk said during an update to Starship in 2019.
“You try to create rather than charge – it’s actually the opposite of an airplane.”
When Starship approaches the ground, it should be slow enough to perform an engine burn that causes the vehicle to rotate in a vertical position. It then uses the Raptors as retro rockets to divert the vehicle to a safe landing.
Musk says that this general approach can be used to drop Starship safely on any planet’s surface in the solar system – including Mars.
When will it fly?
Over the past few years, SpaceX has been testing different prototypes of the Starship upper stage at its Boca Chica facility in Texas.
The company started a 39-meter-long ‘test article’ called Starhopper, which had a passing resemblance to a water tower. Since the vehicle flew up to 150 meters above the ground, SpaceX has been developing more and more complex Starship prototypes.
In December 2020, SpaceX launched a test article called SN8 (Starship number 8) – the first with a nose cone and valves. After reaching an altitude of 12.5 km, the SN8 belly bounced back to Earth, giving SpaceX valuable engineering data on the last part of Starship’s return from space.
It was almost a manual flight, but the vehicle approached the runway slightly too fast and hard, causing it to crumble and explode. SpaceX has already moved the prototype SN9 to the launch platform, and this time they want to hold the landing.
In October 2020, Elon Musk said SpaceX intends to launch Starship on an unmanned flight to Mars in 2024.
Some observers note that the timelines of Mr. Musk is sometimes optimistic. But he has also developed a reputation for ultimately achieving his goals, no matter how ambitious.
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