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Everything you need to know about Starship's third test

plus a breakdown on what Starship is!

This week, SpaceX is planning on launching their interplanetary vehicle Starship on its third test flight. It’s the largest and the most powerful rocket ever built — bigger than NASA’s Space Launch System, bigger than the Saturn V rockets that took Apollo astronauts to the moon, bigger than the Soviet N1 moon rocket. If you want to know more about Starship, or the particulars of this mission, you’re at the right place.

Credit: SpaceX

Let’s start with what Starship is. Fully stacked, it stands 394 feet, or 120 meters, high. It’s a two-stage launch system, with a first-stage booster, called Super Heavy. The second stage is Starship, and it is designed to carry cargo or passengers or both. The big thing about Starship is that it can transport huge payloads to space. 

Here’s the low down on Starship and Super Heavy

Currently, SpaceX has their workhorse rocket the Falcon 9, as well as their heavy lift variant, the Falcon Heavy. The current iteration of the Falcon 9 rocket maxes out with an expendable rocket flying around 50,265 lbs or 22,800 kg to low Earth orbit. The Falcon Heavy can lift 140,660 lbs or 63,800 kg, while Starship? There are a few numbers out there, but it’s safe to say that the rocket will be able to handle at least 100 metric tonnes, or 220,462 lbs to orbit. So it’s a bit of a difference. 

Falcon 9 rocket, credit: SpaceS

It’s important to note that Falcon Heavy is basically a modified version of the Falcon 9. It’s essentially just three Falcon 9 boosters strapped together, with a reinforced center core. You can think of it as an iteration on SpaceX’s flagship rocket. It’s essentially the same technoloogy, they both have Merlin engines and use liquid oxygen and rocket-grade kerosene as propellant. 

Falcon Heavy rocket, credit: SpaceX

Starship is a completely different beast. I’m sure much of the flight software is the same, but here’s the key: The Super Heavy booster has 33 raptor engines that run on methalox, or liquid methane and oxygen, propellant. It’s cleaner burning than other rocket fuels, it’s more efficient, it costs less, and the materials are available on other worlds, which means astronauts on Mars could create the fuel locally to return home. It’s considered next-gen rocket propellant in a lot of ways.

Starship also fully reusable — so, like the Falcon 9 and Falcon Heavy boosters, the Super Heavy will perform a boostback burn and come back to Earth for a safe landing.

Falcon Heavy booster landing, credit: SpaceX

Starship, the second stage, also has its own six Raptor engines that theoretically will be capable of taking it wherever it needs to go. The idea is Super Heavy is just to get Starship out of the drag of Earth’s atmosphere. Then the upper stage can manage on its own into space or come down for a safe, controlled landing.

That’s part of why this is so complicated — SpaceX is basically testing two different spacecraft every time they launch Starship. And both are supposed to be fully reusable. 

With a launch suite like Falcon 9, which is by far the most launched rocket in the world, and the Falcon Heavy, you might wonder why SpaceX needs a third rocket? Well, the entire point of what SpaceX is doing is basically just reducing cost to take cargo to low Earth orbit. If you get what you need to into LEO, you’re halfway to wherever you need to go. 

The hard part is putting stuff into orbit, especially if you’re trying to haul heavy cargo, habitation modules for outposts on other planets — that’s why the International Space Station was constructed in pieces, because it’s a lot easier to take up smaller pieces and build things in space than it is to construct something large on Earth and figure out a way to launch it. The idea is eventually, Starship will bring down launch costs enough to where it will replace both the Falcon 9 and Falcon Heavy.

Bringing the cost of accessing low Earth orbit down

SpaceX has been consistently bringing launch costs down thanks to the reusability of its rockets. Currently the launch cost of a reusable Falcon 9 rocket is around $67 million (we don’t have the precise pricing for an expendable Falcon 9, but it can be up to $100 million). We also don’t have clear numbers for how much a fully loaded reusable Falcon 9 rocket can manage to low Earth orbit, but it’s probably around maybe 18,000 kg, or 39,600 pounds. 

Falcon 9 launch, credit: SpaceX

The reusable Space Shuttle was originally designed to bring down the cost of access to space (but in practice the orbiters were so delicate they had to fully refit them between every launch). The pricing for a Space Shuttle launch was about $1.5 billion to launch 27,500 kg to low Earth orbit. If you do the math, it’s a difference of $54,500/kg versus somewhere around $3,700/kg for a Falcon 9. 

This is also why I don’t really take it seriously when people try to compare NASA’s SLS rocket and Starship. Yes, Starship and SLS are both intended to be interplanetary rockets, but SLS will end up costing around $4.1 billion PER LAUNCH. Like development in any other industry, usually, the first launch is extremely expensive, and then once the rocket succeeds, the costs come way down.

Credit: Swapna Krishna

But SLS will always be expensive. A report from NASA’s Office of the Inspector General makes it clear that the production costs will continue to be around $2 billion per rocket. 

The Space Launch System is old technology, which comes in contrast to Starship’s pushing the envelope. SLS’s RS-25 engines were literally ripped out of the Space Shuttle and reused for SLS — the intention was to keep costs down by using tried and tech. Future SLS rockets will use a modified RS-25 engine, but according to that OIG report, the cost for the four engines is over half a billion dollars per flight — and SLS isn’t reusable. 

Credit: NASA OIG report

It’s so bad that NASA’s Office of the Inspector General actually recommended that NASA look to commercial launch providers to achieve their cost reduction goals for the Artemis program, because it will just never happen with SLS.

I’m not trying to make this NASA versus SpaceX, and dunk on NASA and praise SpaceX. I certainly have my criticisms of SpaceX, and I don’t think it’s a secret I think NASA does a great job at a lot of things. And SLS performed very well during its first flight on Artemis I. But it’s also sickeningly expensive, which is one reason we’re all watching Starship.

The success of Starship is also crucial to NASA’s Artemis program in another way. The Human Landing System, or HLS, is a spacecraft that astronauts will board in orbit of the moon. It will transport them to the lunar surface, and then take them back to lunar orbit again when they’re ready. 

Credit: NASA/SpaceX

HLS is just a modified version of Starship, so NASA will be watching this launch very closely as well. If they want to meet the current goal of September 2026 for Artemis III, the first crewed moon landing of the Artemis program, then they really need SpaceX to succeed here.

The flight plan for March 14

Now, let’s talk about what to expect on the test flight on Thursday.

Credit: SpaceX

I talked about the amazing capabilities of Starship, but it’s important to note that we won’t see much of this on Thursday. What SpaceX is launching this week, assuming that they obtain a launch license from the FAA in time, is just a test. They’re not going to actually do all these things that I just talked about, because the main purpose here is just a demonstration of the hardware and an accomplishment of a few test objectives. 

The launch is currently scheduled for Thursday morning, March 14, and SpaceX will livestream it on their website. The livestream is currently scheduled to begin at 7:30 am ET, which would be about 30 minutes before when they hope to launch. I’ll also have a rundown of what happened during the mission later in the day, whenever it launches.

It can be hard to cover SpaceX, especially on these test flights, because they guard information very carefully. But here’s what we do know about the flight. 

The aim is to launch from their spaceport in Boca Chica, Texas. After stage separation, which happens at 2:44 after liftoff, the Super Heavy booster will flip and perform a Boostback burn (this is where the first test went wrong, the first stage didn’t separate properly, so when Super Heavy went to do its flip, the second stage was still attached). It’s supposed to splash down in the Gulf of Mexico.

Meanwhile, the upper stage, Starship, will continue its ascent. I think it will stay suborbital, so this won’t be an orbital flight. During this test, it will attempt to open and close its payload door, perform a propellant transfer demonstration (basically transferring propellant from one tank to another, a preview of on-orbit refueling technology),  and interestingly, the first-ever relight of a Raptor engine while in space and controlled re-entry of Starship. 

This is super interesting, because they’re targeting a new splashdown location for Starship in the Indian Ocean an hour and four minutes after liftoff. They haven’t specifically told us why, but reading between the lines of what we do know, it’s probably because if the raptor engine test goes sideways, then they don’t want to hit Hawaii on their way down — but it could be for some other reason. This also means the weather in the Indian Ocean will be a factor in the decision on whether to launch. 

Landing location, credit: Jonathan McDowell

There was a lot of talk about the “failure” on Starship’s first two test missions, while every space reporter and analyst I know was marveling at the success. Things blowing up and learning from what goes wrong is a tried and true component of building rockets and spacecraft. But we’re on the third test flight now, so let’s talk about what I would consider a success for this.

The second test, which I thought was successful because it improved on the previous one, ended soon after the first stage separation. I think they need to demonstrate they can achieve the basics — launch, ascent, stage separation, and the successful splashdown of the booster. The rest — the propellant demonstration, the payload door — is extra. 

Notice I didn’t mention Starship’s successful re-entry, because if they succeed at that objective, this will be an incredible success. I think that’s going to be the hardest part, the relight of the Raptor engine in space and then the controlled re-entry. I think that will be the single biggest point of failure because of the stresses involved. But we’ll see what happens.

And THAT is just about everything you need to know about Starship, and this upcoming test launch.