The SpaceX Starship system is a fully-reusable two-stage-to-orbit, super heavy-lift launch vehicle under development by SpaceX since 2012, and is a self-funded private spaceflight project. Integrated system testing of a proof of concept for Starship began in March 2019, with the addition of a single Raptor rocket engine to a reduced-height prototype, nicknamed Starhopper.
SpaceX is planning to launch commercial payloads using Starship no earlier than 2021. In April 2020, NASA selected a modified human-rated Starship system as one of three potential lunar landing system design concepts to receive funding for a 10-month long initial design phase for the NASA Artemis program.
While the name of the vehicle has changed many times over the years, the combination of Starship spacecraft and Super Heavy booster is called the “Starship system” by SpaceX in their payload users guide. Sometimes, as on the SpaceX website, the term “Starship” is used as a collective term for both the Starship spacecraft and the Super Heavy booster.
In January 2019, Elon Musk announced that the Starship would no longer be constructed out of carbon fiber, and that stainless steel would be used instead to build the Starship. Musk cited several reasons including cost, strength, and ease of production to justify making the switch.
In 2019, the cost per launch for Starship was estimated by SpaceX to be as low as US$2 million once the company achieves a robust operational cadence and achieves the technological advance of full and rapid reusability. Musk clarified that SpaceX intends to fly exclusively cargo transport missions initially, and that passenger flights would come only much later.
Musk says. “Starship will fly hundreds of missions with satellites before we put people on board.” Starship is planned to eventually be built in at least these operational variants:
- Spaceship: a large, long-duration spacecraft capable of carrying passengers or cargo to interplanetary destinations, to LEO, or Earth to Earth spaceflight.
- Satellite delivery spacecraft: a vehicle able to transport and place spacecraft into orbit, or handle the in-space recovery of spacecraft and space debris for return to Earth or movement to another orbit. This is shown with a large cargo bay door that can open in space to facilitate delivery and pickup of cargo.
- Tanker: a cargo-only propellant tanker to support the refilling of propellants in Earth orbit. The tanker will enable launching a heavy spacecraft to interplanetary space as the spacecraft being refuelled can use its tanks twice, first to reach LEO and afterwards to leave Earth orbit. The tanker variant, also required for high-payload lunar flights, is expected to come only later; initial in-space propellant transfer will be from one standard Starship to another.
- Lunar-surface-to-orbit transport: a variant of Starship without airbrakes or heat sheilding that is required for in-atmosphere-operations. Additionally the ship will be equipped with a docking port on the nose and have white paint (as opposed to the bare steel planned for regular Starships). On 30 April 2020, NASA selected SpaceX to develop a human-rated lunar lander for the Artemis program, therefore requiring SpaceX to develop an approach for a direct lunar landing.
According to Musk, when Starship is used for beyond Earth orbit (BEO) launches to Mars, the functioning of the overall expedition system will necessarily include propellant production on the Mars surface. He says that this is necessary for the return trip and to reuse the spaceship to keep costs as low as possible.
A modified version known as the Starship Human Landing System (Starship HLS) was selected by NASA in April 2020 for potential use for long-duration crewed lunar landings as part of NASA’s Artemis program. (Wikipedia)