SpaceX's jumbo 400-foot-long Starship rocket took off from the Texas Starbase site Thursday morning for its fourth test flight, resulting in its most successful run yet. All three previous tests ended in explosions.

The unmanned craft is classified as a super heavy-lift launch vehicle and is lauded as the biggest and most powerful rocket ever built. Working toward an ultimate goal of delivering astronauts back and forth between the Earth, moon and even Mars, SpaceX has called each previous test flight an improvement on the last.

SpaceX provided live coverage of the launch on the SpaceX website and X, formerly Twitter, account. The company has been provided millions in funding from NASA in hopes of producing a commercial rocket that can safely take astronauts to the moon by 2026.

Here is what happened during the Starship's fourth test launch and its previous test flights.

Starship test launches:Here's what happened in first 3 SpaceX Starship test launches

SpaceX Starship successfully splashes down

Roughly 49 minutes into the flight, Starship began its reentry into the Earth's atmosphere.

The Starship's heat shields protected the craft as the atmosphere naturally slowed its descent without the use of engines to navigate toward the Earth's surface.

About 57 minutes into the flight, external cameras on the craft caught one of the heat shields sparking and debris ripping from the ship's exterior. While the damaged camera made for a spotty livestream, flares of light prompted rounds of cheers from the crowd watching at the launch site.

Roughly one hour and six minutes into the flight, Starship successfully completed its first-ever landing burn and splashed down into the Indian Ocean to raucous applause.

"Splashdown confirmed!" SpaceX shared on X moments after landing. "Congratulations to the entire SpaceX team on an exciting fourth flight test of Starship!"

SpaceX Starship booster successfully splashes down

Around 7 minutes and 20 seconds into the flight, the craft's booster successfully separated and splashed down in the Gulf of Mexico. All six of Starship's engines powered it into successful orbital insertion.

SpaceX Starship takes off

The SpaceX Starship spacecraft lifted off from SpaceX’s private Starbase site in Boca Chica, Texas at 8:50 a.m. E.T. on Thursday.

This time, 32 of 33 booster engines lit as the craft launched. Roughly three minutes into the flight, the ship successfully began traveling on its own without the assistance of the booster.

What is the goal of the Starship test launches?

The improving test launches are a positive sign for SpaceX and NASA, which awarded the company a $2.9 billion contract in 2021 to develop the first commercial human lander for its upcoming Artemis III mission to the moon slated for 2026.

NASA agreed to pay Elon Musk's company the hefty sum in hopes SpaceX will develop a spacecraft able to transport astronauts to the moon's surface.

"We’re continuing to rapidly develop Starship, putting flight hardware in a flight environment to learn as quickly as possible as we build a fully reusable transportation system designed to carry crew and cargo to Earth orbit, the Moon, Mars and beyond," said the space company in a post on X, formerly Twitter.

NASA originally intended to launch this mission and its Artemis II astronauts into orbit by the end of the year on a 10-day trip circumnavigating the moon. The space agency then planned a moon landing for one year later, part of the Artemis III mission. However, the program missions have since been delayed by at least a year after NASA encountered a slew of issues.

NASA intends to eventually send a crew to the moon's unexplored south-polar region in a mission that would be the first of its kind in American history since the Apollo program ended in 1972.

What happened during previous Starship test launches?

SpaceX's Starship has had three previous test launches since April 2023. While all three ended in explosions, each one "made tremendous strides" toward the ultimate goal of developing rapidly reliable reusable rockets.

Starship got off to a rough start when it exploded just four minutes into its inaugural test flight on April 20, 2023.

The craft launched from the Starbase site, but several of the craft's engines failed to ignite, triggering an explosion before the booster and spacecraft were able to separate. The rocket's flight termination system was activated to destroy the tumbling vehicle, which reached a total height of about 24 miles above the ground.

The second launch attempt on Nov. 18, 2023 saw the craft survive longer and reach new milestones.

This time, the booster was able to successfully separate from the rocket, which reached space before the ground crew lost communication with it after nine minutes. Three minutes later, SpaceX lost both the booster and the spacecraft in two explosions.

All 33 booster engines fired as designed in this launch, and the ship reached an altitude of 92 miles.

The third test launch, which took place on March 14, saw Starship successfully separating from the booster and making it to orbit shortly after launch.

A series of in-flight tests were conducted until Starship began to make its way back into the Earth's atmosphere, at which point signal to the craft was lost and about an hour into the mission and it was concluded the craft likely broke apart.

SpaceX said this flight reached several more milestones, including the first reentry from space, first opening and closing of the craft's payload door in space and a successful propellant transfer demonstration.