The massive SpaceX rocket explosion just 4 minutes after launch highlights how far the goal of sending humans to the Moon and Mars still is.
On the evening of April 20, SpaceX’s Starship, the most powerful rocket ever built aimed at transporting crews for future space exploration, had its first test launch. Four minutes after liftoff, the rocket exploded in mid-air.
SpaceX engineers are still investigating the cause of the launch failure. It appears that some of the 33 Raptor engines caught fire. Within 3 minutes after takeoff, the lower half of the rocket—the Super Heavy booster—was supposed to detach from the upper half, the Starship, but that did not happen. Instead, the Starship began to spin wildly, tumbling through the sky before exploding. SpaceX stated that they intentionally sent a command to detonate to end the flight.
Successes and Failures in the April 20 Launch
Despite the early termination of the test, SpaceX still achieved some successes. This was the first time the Super Heavy, the large cylindrical booster containing the propellant necessary to lift the Starship out of Earth’s gravitational pull, flew in the air. The company also collected data during the flight that could be applied to future tests in the coming months, as Elon Musk shared on Twitter.
It is rare for a commercial rocket to succeed on its first launch, and SpaceX itself endured 3 failures before successfully launching the Falcon rocket into orbit on its fourth attempt. Currently, the Falcon 9 is the most frequently used rocket for space missions. However, the Falcon 9 is smaller and partially reusable, while the Starship is designed for larger payloads and full reusability.
The Starship rocket just before takeoff on the evening of April 20. (Photo: SpaceX).
However, the failure of Starship to detach from Super Heavy, one of the initial steps in the launch process, indicates the challenges ahead for Musk’s grand plans. The billionaire hopes this rocket will usher in a new era of space exploration, transporting people and cargo to the Moon and even Mars.
First and foremost, SpaceX needs to prove that Starship can reach orbit, then return to Earth and land safely.
One of the standout features of this rocket is its size, standing nearly 120 meters tall. It is also the most powerful rocket in history. Both of these factors mean that to reach orbit, Starship consumes a lot of fuel, and even more if it aims to carry humans to the Moon and back.
Therefore, flights will need to refuel mid-journey, similar to a car needing to stop for gas. Refueling a rocket like this in space has never been done before, and the super-cooled propellants being used make this mission even more challenging.
With the April 20 test, SpaceX did not achieve the first step of putting Starship into orbit.
An even greater challenge is figuring out how to refuel the spacecraft in outer space. This process is akin to launching a gas station into orbit, then sending a fleet of “fuel truck” ships to refuel the station, and then finding a way to transfer fuel between the station and the ships in a zero-gravity environment.
What to Expect from the Most Powerful Rocket?
Musk has stated that fully reusable vehicles like Super Heavy and Starship will enable multiple flights, significantly reducing the cost to reach orbit and creating a previously non-existent pathway into space.
An illustration of the rocket transporting humans to the Moon. (Photo: SpaceX).
The U.S. government is also betting on the success of this project. The National Aeronautics and Space Administration (NASA) has committed at least $2.9 billion to help develop Starship into a vehicle capable of landing NASA astronauts on the Moon’s surface as part of the Artemis program. This rocket is also seen by SpaceX as a key component in the vision for exploring the Solar System and commercializing space.
It is difficult to estimate how much SpaceX has spent on Starship and how much more it will spend to realize these goals. Musk mentioned in 2018 that the total development cost was expected to be no more than $10 billion. This projected figure has not been updated, and the company has not disclosed any financial information.
Before the April 20 launch, when asked how much SpaceX had spent on developing Starship, Musk did not answer directly. “The specific cost of this vehicle really doesn’t matter,” the SpaceX CEO said.
“For example, if you build a soap factory, the first bar of soap will cost $10 million. But that’s not really the price of a bar, as the cost will decrease with mass production,” Musk elaborated, explaining that the goal is to reduce the cost to $2 million per flight.
Timelines for completing Starship have not been announced. NASA has stated that the agency will utilize SpaceX’s vehicle to send humans to the Moon by 2025, although the company is known for repeatedly missing its self-imposed deadlines. The first crewed flight was supposed to take place earlier this year.
The moment Starship exploded 4 minutes after takeoff on the evening of April 20. (Photo: Reuters).
Once Starship can achieve stable orbit, SpaceX will first use the vehicle to launch various payloads into space, including next-generation Starlink satellites, which are larger and aimed at increasing capacity for satellite internet service. However, to send humans deep into space, such as to the Moon, Mars, and back to Earth, the spacecraft will need to refuel en route.
A Series of Technical Challenges Await SpaceX
“Getting this monster into orbit is a challenge, and refueling is the next technological challenge,” Gwynne Shotwell, SpaceX’s CEO, stated at an industry conference in Washington in February.
Refueling for SpaceX will not be as simple as pumping gas. Starship’s fuel consists of two cryogenic propellants, liquid oxygen and liquid methane, both of which must be kept at temperatures around -180 degrees Celsius. If they heat up, the fuel will turn into gas and evaporate.
Keeping the fuel cool in space is very challenging. While orbiting Earth, the fuel ship will spend half its time in freezing darkness and half its time in direct sunlight. To avoid pressure buildup that could lead to catastrophic consequences, the ship needs a venting system to release evaporated fuel.
The most powerful rocket ever built, Starship, still faces many technical hurdles before it can be operational. (Photo: SpaceX).
SpaceX will also have to transfer these cryogenic liquids from the fuel ship to the station and then from the station to the crewed ship. The back-and-forth transfer also causes the fuel to warm up, and engineers have never worked with such large volumes of these substances in a weightless environment.
“There are a lot of things we are not certain about. The transportation of cryogenic fuel in space is still not well understood,” stated Lauren Ameen, Deputy Director at NASA’s Cryogenic Fluid Management Office.
It remains unclear when SpaceX will demonstrate that they can transfer propellant between ships in space. For the first orbital flight, SpaceX may need at least another 6 months, and possibly longer, according to Lisa Watson-Morgan, NASA’s Program Director for landing systems under the Artemis program.
NASA still believes it is possible for Starship to reach the Moon by 2025. “I am fully confident that NASA and SpaceX will achieve that,” Watson-Morgan said. But first, SpaceX will need to prove that the spacecraft can reach space without exploding.
