Featured Image Source: SpaceX
SpaceX ultimate goal is to build a sustainable city on Mars by the year 2050. The rocket company is in the initial phase of developing a multi-purpose reusable spacecraft-rocket duo to complete the mission, Starship and its Super Heavy rocket booster. The first flight prototypes of the craft are under development at their South Texas facility in Boca Chica Beach, Brownsville, TX. SpaceX founder, Chief Engineer Elon Musk, stated teams aim to manufacture as many as 20 test flight vehicles -Starship SN1 through SN20- this year. Engineers will build many Starship prototypes in order to test different features that will aid in the development of a space-ready craft. Sometime after March 16, Starship SN1 will finalize assembly to perform a 20 kilometer test flight above Boca Chica Beach. SN1 was moved to the launch pad this week where teams will finish its assembly, attach a Raptor engine, and conduct preflight preparations.
Starship SN1 tank preparing for Raptor attachment & static fire pic.twitter.com/jx0ijLrxWx
— Elon Musk (@elonmusk) February 25, 2020
The final version of Starship will be capable of carrying 100 passengers plus over 100 tons of cargo powered by 6 Raptor engines with propellant capacity of up to 1,200 tons that will enable long-duration voyages to the Moon and Mars. The Super Heavy rocket booster will only be used to carry Starship out of Earth's atmosphere into orbit, then it would return from space to land on a spaceport at sea in order to be reused.
Starship and Super Heavy are powered by Raptors, a new type of rocket engine developed and manufactured by SpaceX. Each Raptor is 1.3 meters in diameter, with a height of 3.1 meters. Unlike the company's other rockets which are powered by Kerosene/LOX, Raptors are a full-flow, staged-combustion engine powered by a combination of cryogenic methane and cryogenic liquid oxygen -a true innovation in the aerospace industry. Musk stated:
“Other rocket engines were designed for no, or almost no reuse. Raptor is designed for heavy and immediate reuse, like an aircraft jet engine, with inspections required only after many flights, assuming instrumentation shows it good.”
The Super Heavy rocket is powered by 37 Raptor engines with thrust capability of approximately 72 meganewtons (MN), which would make SpaceX's Starship the world's most powerful rocket in comparison to the 35 MN thrust of Saturn V rocket that took humans to the moon during NASA's Apollo mission. Starship will be powered by 6 Raptors, including 3 sea level Raptors designed for atmospheric flight, and 3 vacuum optimized Raptors for propulsion in space. Each Raptor engine could produce over 200 tons of thrust at full throttle!
Starship will become the world's most powerful rocket in history! Enabling humans to embark on voyages to the Moon, Mars and beyond!
3 on SN2
— Elon Musk (@elonmusk) February 25, 2020
Starship SN1 will perform its first test flight with a single Raptor. Musk said 3 Raptor engines will be tested on SN2 -the next Starship prototype in the production line to test. So, future prototypes will eventually increase the number of Raptors used in flight. Last year, SpaceX performed a 150 meter test flight with a scaled-down prototype using one Raptor engine, and successfully landed the vehicle on a nearby launch pad (video below).
SpaceX announced this morning that they have tested 18 Raptor engines at their manufacturing facility situated in McGregor, Texas. Engineers use a test stand that holds the Raptor to the ground while the engine is briefly ignited for a few seconds to asses if it works at optimal levels, the company stated:
"Third Raptor test stand activated at SpaceX’s rocket development facility in McGregor, Texas. In the past year, the Raptor team has accumulated over 3,200 seconds of testing across 18 engines, including multiple full-power firings."
Testing Raptor in vertical configuration (on the giant tripod) should allow us to simplify some aspects of the engine design
— Elon Musk (@elonmusk) February 27, 2020
Musk said that "Testing Raptor in vertical configuration (on the giant tripod) should allow us to simplify some aspects of the engine design." Some of the engines in McGregor might be shipped to Boca Chica whenever more Starship vehicles are built. The Raptor engine is special, SpaceX engineers designed it with Mars in mind, to enable astronauts to build refueling stations upon arrival. Since Raptors are powered by a combination of sub-cooled methane plus liquid oxygen, future Martians could dig water ice from the Red Planet's soil and capture carbon dioxide from the atmosphere, in order to synthesize methane and liquid oxygen by using electrolysis and the Sabatier process to create fuel.