A revolutionary leap toward interplanetary travel

Space exploration has always been a boundary of human imagination, pushing the boundaries of technology and expanding our understanding of the universe. NASA and many other organizations have already carried out remarkable missions of landing on the Moon and exploring Mars with spacecraft. These efforts have significantly contributed to our knowledge of space but still, the concept of interplanetary travel and colonization remains a grand ambition. Elon Musk has taken a bold step toward realizing this dream through his company SpaceX. Musk is working on a new idea of transportation that envisions human travel from one planet to another. Starship is the latest development in this journey, designed to transport humans and cargo to Mars, the Moon and beyond.

Musk founded SpaceX in 2002 and from that date, it has already achieved several space milestones including the development of reusable rockets like the Falcon 9 and the first private spacecraft to deliver cargo to the International Space Station (ISS). These successes have paved the way for the development of the most powerful and advanced spacecraft ever built—Starship. SpaceX has launched several different versions of spacecraft before the development of Starship. The Dragon was the company’s first major spacecraft designed to transport cargo and crew to the ISS. With the development of Dragon 2, SpaceX solidified its position as a leader in the space industry as it was allowed for human spaceflight. With the development of Falco 9, a reusable rocket, the company marked a significant turning point in space exploration by drastically reducing the cost of launch. Starship is the result of all these earlier projects, which marked a major leap in terms of technology and scale. Unlike previous spacecraft, Starship is designed with interplanetary travel in mind, making it a key component of Musk’s vision for colonizing Mars.

The most advanced spacecraft SpaceX has developed to date, the Starship is designed to carry up to 100 passengers or 100 tons of cargo to various destinations in space. The spacecraft is made of stainless steel and carbon fiber.  The use of stainless steel is a significant shift from the lightweight aluminum-lithium alloys used in many traditional spacecraft, as it provides a better balance of strength, temperature resistance and cost-effectiveness and it can withstand the extreme conditions of space travel. The Starship consists of two stages: Stage 1 and Stage 2. The lower part responsible for providing the necessary thrust to launch the spacecraft into orbit is Stage 1, which is also known as Super Heavy booster. It measures 71 meters in height with 9 meters in diameter and is powered by 33 Raptor engines, which generate a total thrust of around 17m pounds (7,700 tons). In the past, boosters were expendable; after launch, they would fall into the sea and be destroyed. However, the Super Heavy booster is designed for reusability. It can return to the launch pad after separating from the spacecraft, allowing for rapid turnaround times and significantly lowering the cost of space travel. 

The upper part of the spacecraft responsible for carrying crew and cargo to their destination is Stage 2, which is the Starship itself. It is 50.3 meters tall with nine meters in diameter and has a payload capacity of 100 metric tons. It is equipped with six Raptor engines, which use liquid methane and liquid oxygen as propellants. This combination is chosen not only for its high performance but also because it can potentially be produced on Mars using the planet's natural resources. This capability is essential for long-term sustainability and the possibility of return missions.

The Starship program has undergone several test flights to date. The first test flight was a suborbital ‘hop’ in which the spacecraft ascended a few kilometers before landing back on Earth. Subsequent Starship flights reached higher altitudes and performed more intricate maneuvers, ultimately culminating in Flight 5. Executed on 13 Oct 2024, Starship Flight 5 marked a significant advancement in SpaceX’s mission to create a fully reusable rocket system, demonstrating major upgrades from its predecessors, such as a redesigned heat shield and enhanced landing mechanisms. The mission involved launching the Starship upper stage toward space, followed by a controlled return of the Super Heavy booster to the launch site. The booster executed a precise landing using ‘chopstick’ arms on the launch tower after separating at an altitude of approximately 74 km, showcasing a novel recovery technique that aims to significantly reduce the time and costs associated with rocket reuse. Starship is designed to achieve re-flight of its rocket booster ultimately within an hour after liftoff. The booster returns within ~5 minutes, so the remaining time is reloading propellant and placing a ship on top of the booster. 

SpaceX refined the design and improved the reliability of the spacecraft with the valuable data from each test. Starship's capabilities are not limited to Mars missions as it is intended for a variety of other roles, such as deploying satellites, transporting cargo to the Moon and even conducting intercontinental travel on Earth.  

As per Elon Musk, the cost of launching a rocket is around $60m. If the rocket is used only once, the entire capital investment is consumed in a single flight. However, if the rocket can be reused 1,000 times, the cost drops to just $60,000 per launch. This dramatically reduces the cost of spaceflight and can bring it closer to the cost of air travel in the near future.

Starship is another important step forward in human space exploration because Mars colonization becomes more realistic with it. The payload of the spacecraft is rather generous and, in addition, it can be refueled in orbit, which makes it possible to deliver everything necessary for the construction of a Martian settlement. Musk envisions a city on Mars with a population of one million people by the 2050s. This ambitious goal involves sending thousands of Starships to the Red Planet, transporting equipment, habitats and settlers in phases. The potential benefits of interplanetary colonization extend beyond survival. Mars could serve as a hub for scientific research, resource mining and even a launch point for future missions to the outer solar system. The Moon, too, could be a valuable destination. NASA’s Artemis program, which aims to return humans to the Moon, may use Starship as a lunar lander to transport astronauts and cargo to the lunar surface. With Earth estimated to be about 4.5bn years old and potentially facing environmental challenges that could threaten its habitability, finding an alternative home for humanity is becoming increasingly important. SpaceX’s vision for Starship is not just about exploration but about ensuring the continuation of human civilization.

Starship represents a monumental step forward in human spaceflight and interplanetary travel. Its advanced design, reusability and cost-effectiveness make it a game-changer in the space industry. SpaceX is advancing scientific knowledge and ensuring a future where humanity can thrive beyond Earth as it aims to establish a human presence on Mars and explore the Moon and other celestial bodies. As countries around the world look to space for new opportunities, the launch of NepaliSat-1 in 2019 stood as a symbolic moment, showcasing the country’s aspirations. Thus, considering Earth’s 4.5bn-year history and the potential environmental threats to its future, SpaceX’s Starship symbolizes a crucial step toward safeguarding the future of humanity beyond our planet.