SpaceX Starship orbital test flight facts for kids

Quick facts for kids
Starship Flight Test

Fully stacked Starship vehicle during its first flight
Mission type	Flight test
Operator	SpaceX
Mission duration	3 minutes, 59 seconds (achieved) 90–100 minutes (planned)
Orbits completed	0 (achieved) <1 (intended)
Start of mission
Launch date	April 20, 2023 08:33 CT
Rocket	Starship
Launch site	Starbase, Texas
Contractor	SpaceX
End of mission
Destroyed	April 20, 2023
Orbital parameters
Regime	Transatmospheric Earth orbit (intended)
Periapsis	50 km (31 mi) (planned)
Apoapsis	250 km (160 mi) (planned)

The SpaceX Starship orbital test flight (called Starship Flight Test by SpaceX) was the first integrated launch of the Starship spacecraft with the Super Heavy booster. Prior to this test, only the Starship upper stage was flown in a series of flight and landing tests. The launch made Starship the tallest and the most powerful rocket ever flown, with twice the thrust of the Saturn V.

The spacecraft was planned to be placed into a transatmospheric Earth orbit where the spacecraft would do nearly one revolution around the Earth, passing through the Strait of Florida, before dipping down and reentering into the atmosphere near Hawaii. The Super Heavy first stage would have performed a controlled landing on the Gulf of Mexico.

The test launched Super Heavy Booster 7 and Ship 24 from SpaceX's Starbase launch site near Boca Chica, Texas. At liftoff on April 20 at 8:33 a.m. CT (13:33 UTC), the rocket had already lost 3 of its 33 booster Raptor engines, and 3 more engines were lost during flight, leading to a total of 6 lost engines. Despite these engine-outs, the vehicle cleared the critical max-q mark. While attempting stage separation, however, the spacecraft went into an uncontrolled spin, and the safety personnel activated the flight termination systems, destroying it at 8:37 a.m. CT (13:37 UTC) over the Gulf of Mexico.

Background

Starship is a super heavy-lift launch vehicle developed by SpaceX. The launch vehicle is the largest and most powerful ever developed with a projected 150 metric tons (330,000 pounds) of payload capacity in a fully reusable configuration, and a height of 120 meters (394 feet). The first stage of Starship is the most powerful rocket ever launched, as its 33 Raptor engines generate nominally more than 16 million pounds of thrust. This is roughly twice that of the Saturn V between 1967 and 1973, more than the SLS produced 8.8 million pounds of thrust at liftoff in 2022, and well above the 10 million pounds thrust from 30 engines that powered the Soviet Union’s N1 rocket between 1969 and 1972.

Both stages are designed to perform controlled landings at the launch site and be reflown multiple times. SpaceX plans to use the launch vehicle for various applications including satellite deployment, space tourism, and interplanetary spaceflight.

Starting in 2019 SpaceX built several prototypes for the upper stage and launched them for a total of 9 times culminating with a launch on 5 May 2021 of Starship SN15 which achieved a soft landing after 6 minutes. After this, SpaceX continued reiterating builds of the upper stages, and completed construction of several first stages, continued ground tests without any flights while waiting for governmental launch clearances. An environmental review of the launch site concluded with the issuing of a 'mitigated FONSI' (Finding of No Significant Impact) ruling in June 2022, requiring the company to implement various mitigations to local wildlife and historical sites but otherwise permitting a launch license to be issued.

A flight readiness review was completed on April 8, 2023. A planned launch rehearsal scheduled for April 11 was later cancelled. The Federal Aviation Administration (FAA) issued an orbital launch license for the vehicle on April 14, 2023.

Flight profile

The spacecraft flight plan was to conduct powered flight until reaching the desired transatmospheric Earth orbit, estimated to be around 250 × 50 km (155 × 31 mi), which would have caused Starship to decay reentry the atmosphere after roughly 1 hour, 17 minutes of flight, after nearly completing a full orbit.

Though both Starship's rocket stages are planned to eventually be reusable, this test flight planned to not make any soft-landing attempts and instead discard both of the rocket stages at the end of their flight. Both the booster and the spacecraft would have performed controlled touchdowns on the ocean surface. According to filings with the Federal Communications Commission, the booster would have performed a boostback burn and targeted a landing about 20 miles (32 km) offshore in the Gulf of Mexico, while the Starship spacecraft would have targeted a landing in the Pacific Ocean about 62 miles (100 km) northwest of Kauai.

April 17 launch attempt

The Starship Super Heavy stack was loaded with propellant and set to launch at 13:20 UTC (8:20 am CT), however, the launch was scrubbed due to a frozen pressurization valve on the Super Heavy booster (first stage) at T-8:05, leading to concerns surrounding the successful pressurization of Booster 7. Prior to the scrub being called, SpaceX control worked on resolving the issue and proceeding with a launch the same day. However, due to little responsiveness from the valve as the clock ticked to ignition, mission control had made the decision to make the most of the propellant and pressure while not placing the entire vehicle at risk. Instead of removing the propellant, SpaceX proceeded with a wet dress rehearsal and halted the timer at T-40 seconds. SpaceX said that that it would require a minimum of 48 hours to refill the propellant for another attempt.

April 20 launch

Radar scans from the National Weather Service radar in Brownsville, Texas

A second, 92-minute long launch window opened at 13:28 UTC (8:28 am CDT) on Thursday, April 20.

The vehicle launched from Starbase, at Boca Chica, Texas, on the United States Gulf Coast. Following a successful launch and tower clearance at 8:33 CDT, three of the 33 Raptor engines were displayed by SpaceX as shut down as the vehicle lifted from the ground. By T+1:07, six Raptor engines had shut down. After successfully passing max q, the booster and spacecraft failed to separate when scheduled at T+2:52, as it appeared to undergo flipping maneuvers without shutting its engines down first.

During the unsuccessful separation of the Starship and Super Heavy booster, which required the rocket to spin to reorient itself, the stack entered an uncontrolled spin, emitting plumes of white smoke. The stages remained attached to each other for over a minute, until the rocket's flight termination system was commanded, causing a controlled breakup of the vehicle. Starship and Super Heavy were terminated separately: Booster 7 was destroyed at T+3:59, Ship 24 exploded at T+4:01. The vehicle reached a peak altitude of 39 km.

Because SpaceX intentionally minimized the launch protection infrastructure (such as not installing a water deluge system or a flame diverter), the rocket caused damage to the spaceport and surrounding infrastructure. At liftoff, the rocket kicked up huge plumes of sand and dust at the pad, with reports in Port Isabel, about 10 miles from the launch site, of particles covered cars and other surfaces, and a shattered window at a local business. The concrete below the rocket and launch mount also appeared to show significant damage.

Reactions

• Bill Nelson, the NASA administrator, and Josef Aschbacher, ESA Director General, both congratulated SpaceX on the launch, with Nelson commenting, "Every great achievement throughout history has demanded some level of calculated risk, because with great risk comes great reward. Looking forward to all that SpaceX learns, to the next flight test—and beyond."
• The company said in a tweet that "today's test will help us improve Starship's reliability as SpaceX seeks to make life multi-planetary," with Elon Musk saying that the team will try to test the rocket again in a few months.
• The Federal Aviation Administration said it would oversee an investigation, a standard practice when a vehicle was lost in flight, and there were no reports of injuries or property damage.
• University of Chicago space historian Jordan Brimm said that "it fell somewhere between a small step and their hoped-for giant leap, but it still represents significant progress toward a reusable super-heavy lift rocket".
• Bloomberg News space reporter Loren Grush said the explosion "highlights the challenges ahead for Musk’s grandiose plan for Starship to open up space to human travel", and that beyond the engineering work required for Starship to successfully land, SpaceX will still need to work on Starship's life support systems and ability to refuel in outer space. Grush also described the booster's first takeoff as a "win", and said that commercial rockets' first launches are rarely successful.