Practice English Speaking&Listening with: SLS VS Starship: Why do both rockets exist?!

Difficulty: 0

- Hi, it's me, Tim Dodd, the Everyday Astronaut.

NASA just announced the lunar landers

for the Artemis program and, to everyone's surprise,

SpaceX's massive Starship

is actually one of the landers that NASA chose

alongside Blue Origin and Dynetics proposals.

Whoa. (chuckles)

And this is bringing up a lot of questions,

some of which we'll answer in my next video,

"Should NASA Just Cancel SLS and Use Starship

"and/or Other Commercial Launchers for Artemis?"

where we're going to dive deep

into why NASA isn't just using Starship entirely,

and why they're only looking to use it as a lunar lander.

But today I think we need to settle

a lot of debates here first

about these two rockets, and now more than ever,

it's time we truly pit them head-to-head.

Because this very well might go down in the history books

as some serious irony

that these two rockets even exist at the same time.

I mean, despite these two vehicles

having very similar capabilities,

you couldn't come up with two more opposite vehicles

with two drastically different engineering philosophies.

I mean, one rocket has been meticulously designed

and built for years and years by seasoned rocket engineers,

and the other is being built in a field in Texas

by a patchwork team of space cowboys,

some of whom previously built water towers.

So today, let's take a look at the history

and progress of Starship and SLS,

including the Orion capsule

and everything else necessary for the Artemis missions,

their design considerations, and lastly, their capabilities.

Once we do that, I think we can answer the question,

how is it possible that two rockets like SLS and Starship

even exist at the same time.

Should they exist at the same time?

I mean one is easily

the most ambitious rocket ever conceived

and actually being worked on,

and the other is living in the past,

I mean, literally reusing old parts

from retired space shuttles.

How on Earth did we even wind up here,

two of the most powerful rockets ever made

going online at roughly the same time?

Well, we've got a lot to cover, so let's get started.

- Three, two, one, liftoff (upbeat music)

- [Neil] That's one small step for man.

- [Dispatcher] (speaking faintly) Test one.

- Before we get too far into this video,

just wanted to give a quick, fun shout-out

to this awesome Lunar Mission shirt that I'm wearing.

At the end of this video, I'll challenge you

to find the Easter egg in this shirt.

We'll talk more about that later at the end.

Okay, have you ever spent two months researching,

shooting, editing and animating a video

only to get it completely done

and find out the day before you were planning to release it

that every single bit of your video needs to be blown up,

and you need to reassemble the scraps?

Oh, yeah, no, no I have no idea what that's like.

If you're one of my Patreon supporters,

you're probably laughing right now

at how different this video is

from just what you saw earlier this week,

which I'll keep up in there, Patreon, for posterity's sake.

So please forgive me

if you can tell that I've shot this video in pieces,

because I have. (chuckles)

but there's a lot of good info that we need to get to.

Because you guys know me,

once I got into the topic of SLS vs Starship,

I maybe got a little too too carried away

answering my own questions,

diving in deep and correcting a lot of assumptions

that frankly, I had wrong.

But I've boiled this topic all the way down,

and we're going to cover all the bases in great depth,

because this one is nuts

and you guys debate this all the time,

so we have a lot to settle.

Now, because we've got so much to cover,

and just like all my long videos,

here's the timestamps if you need a reference for later.

But seriously, don't skip through this video.

You'll be shocked at some of the things that I learned,

at least about the history and the progress,

and of course, some of the conclusions as well.

And I've got quick links to these topics

and an article version of this video in the description too.

Okay, right off the bat, we've gotta make one thing clear.

NASA and SpaceX are not competitors.

If you love SpaceX, you can thank NASA for that.

NASA is SpaceX's biggest customer

and their biggest supporter,

so let's keep that in mind.

As if that wasn't obvious now

that NASA is literally investing in Starship

for the Artemis program

and seeing NASA plastered all over SpaceX's Falcon 9 rocket

for the Commercial Crew Program,

the relationship with NASA and SpaceX

goes back to pretty much the beginning of SpaceX.

I mean, after all,

if it weren't for NASA's initial investment

of nearly $400 million for the Falcon 9 and Dragon capsule,

then plus the multi-billion dollars

for the CRS and commercial crew contracts,

SpaceX most certainly wouldn't be where they are today.

NASA does incredible things, vital research and science

that no private company would or really ever could do,

and they do a lot of behind the scenes things

that can often go unnoticed.

In my last video that compared SLS and Starship

two years ago, back in the Tim inexplicably wore

a high altitude Russian flight suit in his bedroom days,

I really drilled into why it's not fair

to compare NASA the organization

directly to SpaceX, the private company.

As you probably know, in general,

I'm team space and I like to encourage

my audience to fight tribalism,

and not just think one thing is the best

and therefore everything else sucks.

But when it comes to NASA building and operating a rocket,

then we can properly compare the pros and cons

of those two systems.

Because I already know there's plenty of you out there

that are, "orange rocket bad, shiny rocket good,"

and vice versa.

So let's come together, sing kumbaya a little,

and celebrate the fact

that we have multiple mega rockets in existence, yes.

Okay, now that the hand-holding's out of the way,

let's define the term super heavy-lift launch vehicle.

So you know why we're not including rockets

like Blue Origin's upcoming New Glenn

or other heavy-lift launchers in this comparison.

The aerospace industry considers a super heavy-lift launcher

as a rocket that can carry more than 50 tons into orbit.

Super heavy-lift launchers

can of course put bigger things into orbit,

but what that really means is having enough capability

to potentially send large things to the moon

or get probes on direct trajectories

to our outer solar system

without time-consuming gravity assists,

potentially getting to outer solar system destinations

almost three times faster.

Historically, there's only been five

super heavy-lift launchers to ever fly,

and only four of those were actually successful.

They're the Saturn V, which could lift 140 tons,

the Soviet Union's unsuccessful N-I

that could have lifted 95 tons,

then there's also the Soviet Union's

twice-flown Energia rocket which could fly 100 tons.

SpaceX's Falcon Heavy technically can loft about 64 tons

if SpaceX chose to expend all three boosters.

Although this has never happened and may never happen,

it does make Falcon Heavy

technically a super heavy-lift launch vehicle.

Although, when all three cores are reused,

its payload capability is more like 30 tons.

And lastly, the Space Shuttle which,

if you include the orbiter

as part of its payload capability,

it could technically put 122.5 tons into orbit.

I should probably point out real quick, by that same logic,

if you included, say, the core stage of the SLS,

which can get into orbit if they wanted it to,

that would in that same way

add another 80 tons to its payload capacity.

But the Shuttle was just a different beast,

and you kind of in some ways had to factor in the orbiter

as payload that went orbital, but the actual,

deployable payload capacity was really only about 27 tons.

Although there was a proposed shuttle C

to make it super heavy, but, okay (chuckles)

tangent, let's keep going.

So if humans are to return to the moon ASAP,

or especially if we're to get to Mars,

we absolutely need to have some serious capabilities.

Of course, I think we're long overdue

for these kinds of missions.

I want humans on the moon again, in 4k!

Actually, let's make is 8k.

Let's just send MKBHD up there with some of his cameras.

Now before we get started with SLS and Starship facts,

in case you've been living under a rock,

we are currently working on getting back to the moon

with NASA's Artemis program,

and a substantial amount of work, funds and goals

have been laid out.

So during this video

you'll hear Artemis thrown around quite a bit.

Although we could lump in

the upcoming Space Station around the moon, Gateway,

into Artemis, we're really just going to focus

on the SLS rocket, the Orion capsule,

and the Human Lander System.

Which to be clear, SLS is to Artemis

as Saturn V was to the Apollo program.

And right now, the Gateway is being skipped

for the first crewed lunar landing or two

and, although a lot of things are drawn up

and in progress for Gateway,

we're just going to focus on landing on the moon

and the hardware that's directly involved in that.

(relaxed music)

We're gonna set some records straight here

before we pit these two rockets head-to-head,

because I think a lot of people have the wrong idea

when it comes to how and why NASA pursued SLS

and Orion in the first place,

and how they fit into the Artemis program.

After the Space Shuttle Columbia tragedy,

NASA started to rethink it's next steps and began looking

to a low Earth orbit replacement to the shuttle

and also started to set its sights on deep space exploration

and needed to build a big rocket in order to do so.

NASA's original vision was the Constellation program,

which would be a crew transportation replacement

for the Shuttle with the Ares I

and a new deep space rocket called Ares V.

After slow progress and massive cost overruns

pointed out in the 2009 Augustine Commission report,

the Constellation program wound up being canceled.

So the NASA Authorization Act of 2010

directed NASA to develop a Space Launch System

capable of lifting 70 to 100 tons to low Earth orbit

and evolvable to 130 tons or more.

The vehicle must be able to lift the Orion Crew Vehicle

since its development was so far along

and NASA was required to work

with existing partners when available.

As we know, NASA,

instead of an Ares 1 low Earth orbit vehicle,

ended up hiring commercial partners to send cargo

and eventually crew to the ISS

with the Commercial Crew Program,

and NASA was tasked with a more focused and leaner rocket.

The thought was to roll out a massive rocket

quickly and efficiently,

as their directive required the vehicle to be operational

by December 31st, 2016. (chuckles) (sighs)

NASA performed a figures of merit analysis

and narrowed it down to five different variations

of a launch vehicle.

Some of them were getting pretty exciting,

with a 10-meter wide core diameter

and oxygen-rich staged combustion engines.

The analysis weighed the options

of affordability being 55%, schedule 25%,

performance 10% and programmatic 10%.

NASA landed on what we now know as the SLS,

and although SLS and Ares V look very similar,

SLS was actually a fairly blank slate design,

but it definitely took cues

from a rocket proposal called DIRECT

in which SLS would lean heavily

on the literal leftover parts

and facilities from the Space Shuttle

as a quick and easy way to prototype

and test out the most powerful rocket ever built.

Unlike the Commercial Crew Program we know today,

NASA would continue to work

with the contractors from the Shuttle

using the familiar cost-plus contracting funding scheme

which basically means, "Here's how much money

"we're going to give you to get it done,

"but we'll also pick up the bill

"on anything that goes over budget."

With funding hovering around 1.5 billion

for SLS development per year since 2011

and the Orion Capsule receiving

a little more than one billion a year,

the contractors were assured to have plenty of resources

to make it happen,

but while staying within a realistic NASA budget

which matched the funding levels during the Shuttle era.

But the problem with cost-plus contracting

is it offers very little incentive to remain on budget

or especially on schedule.

In fact, timeline slips literally means more money

for the contractors, and the prime contractor for SLS,

Boeing, set to receive the most money for the project.

Although NASA does performance reviews of their contractors,

they've been scrutinized for being too easy on some of them,

more on that later.

So in order to keep some of those contractors,

employees, and members of congress happy,

keeping the rocket's heritage close to the Space Shuttle

ensured that funds would continue to be appropriated

to Shuttle contractors, or so the thought was.

So although SLS does literally seem

like a giant wingless space shuttle,

it's actually had many changes

to make the vehicle have higher performance

and lower costs than Space Shuttle's parts.

Here's a quick rundown on the changes.

The SLS will have five-segment solid rocket boosters,

as opposed to the four-segment SRBs the Space Shuttle had,

lacking any recovery hardware

and featuring a redesigned plug

that keeps squirrels and stuff out of it,

with the redesign ensuring debris won't potentially damage

the nearby RS-25 nozzles on ignition.

The core stage, which,

although it looks like a Space Shuttle's external fuel tank,

there's virtually nothing in common

with the external fuel tank

other than its color and its 8.4-meter diameter.

It uses a new aluminum, AL 2219,

different construction and welding techniques,

and even a different spray foam.

People definitely tend to think

it's literally a stretched external fuel tank,

me included, but again, it shares almost nothing in common,

mostly because SLS will have structural loads

going down through the top of the tank

as opposed to hanging off the side of the tank.

The RS-25s have been tweaked

quite a bit since the Space Shuttle

and have increased their power output

from 104.5% to 109%, or 111% in an emergency.

But again, just like the SRBs, the RS-25D

and later the RS-25E variants

will of course not be recovered on SLS.

Just a fun side note, those percentage numbers

are based on the original rated thrust

of 1.6 meganewtons at sea level.

After some tweaks in the Space Shuttle's main engines,

they wound up being able to be throttled up

beyond their original design during the Shuttle's program

and are being pushed even further with SLS.

Another cost-saving and timeline-helping decision

was to initially fly the SLS

with quite literally the upper stage

from ULA's Delta IV and Delta IV Heavy

known as the Delta Cryogenic Second Stage, or DCSS,

only it's been modified

to fit on top of the 8.5-meter wide core stage,

have different hydrogen tanks,

and more reaction control fuel.

This configuration is known

as the Interim Cryogenic Propulsion Stage, or ICPS.

SLS is intended to have a much more powerful upper stage

known as Exploration Upper Stage,

which is considered to be part of the Block 1B upgrade

and makes SLS much more capable.

Next, we need to talk about the Orion capsule.

It sits on top of this whole vehicle

for the Artemis missions.

The Orion Capsule is a fairly traditional crew capsule

and in some ways is a newer and embiginated version

of the Apollo capsule.

But although it looks quite similar,

it's a lot bigger than it might appear.

At five meters wide

versus the Apollo capsule's 3.9 meters wide,

and sporting an impressive nine cubic meters of volume,

compared to 6.2 cubic meters, it'll be quite a bit roomier

and capable of up to six astronauts,

although it'll probably only fly four

for the Artemis missions, versus Apollo's three,

which could technically fit five.

Well, barely.

The Orion capsule used to be called

the Crew Exploration Vehicle

when it was in development for the Constellation program.

But it has changed quite a bit

and now features another cost savings measure,

which is a service module

based on ESA's Automated Transfer Vehicle.

But one thing we need to mention

that's still new to this whole line-up,

and it's still in progress,

and is definitely required for the Artemis program

to land on the moon,

and that is of course the actual lunar lander.

And that brings us to today.

So far, everything we've talked about and discussed

is only capable of getting humans into lunar orbit

with SLS and Orion, because there really

still isn't the capability

to also carry up a lunar lander with SLS Block 1,

or even the upgraded Block 1B.

But NASA has officially selected

three very, very different lunar landers

for the Artemis program, and each one has until 2021

to draw up exactly how they'll get their landers

to the moon.

You know some proposals could actually wind up

still sending modules alongside Orion

in the upgraded Block 1B SLS.

But to get to the moon for Artemis 3,

which will use a Block 1 SLS,

the lander will need to fly on a separate commercial rocket,

or two, or three, or another SLS,

depending on how big this thing ends up being,

because Artemis hardware is big.

This portion of Artemis

is a lot closer to the Commercial Crew Program

than it is to SLS and Orion.

NASA has just a set of requirements,

but is letting the contractors put out proposals,

and doing so in a way that's incredibly quick and ambitious

in the best attempt to get humans on the moon by 2024.

NASA will not own and operate the spacecraft

like they do for SLS and Orion.

So this does mean that we will need

at least two rockets per crewed mission to the moon

for the Artemis program,

likely even three, maybe even four.

So we'll talk more about the options

the Human Lander Systems proposals

could use in the next video

when we look at what other options NASA has,

if they just full blown canceled SLS

in favor of Starship and other commercial options.

So, let's talk about Starship.

(relaxed music)

If you're new to the scene of Starship, or SpaceX,

you might not realize how far back this thing actually goes.

Basically, since SpaceX started,

there's been talks of doing a BFR, or a Big Falcon Rocket.

And, unlike SLS, the actual engineering and development

had mostly been behind closed doors since the early days.

And really, going back before SpaceX's start,

propulsion engineer and employee #1, Tom Mueller,

had built a BFR rocket engine

in his high-powered rocket club, Reaction Research Society.

And yes, the naming scheme does stem from "Doom's" BFG.

Fun side note, Tom's BFR engine was a pintle injector engine

that was targeting 10,000 pounds of thrust.

And Tom was facing off against David Crisalli,

who built a more traditional flat-face injector.

Tom's design won out and eventually kind of became the basis

for the Merlin engine.

But the BFR vehicle

didn't really gain any public notice

until around 2012 when Elon would mention a huge rocket

dubbed Mars Colonial Transporter

that SpaceX would add to their lineup.

But at this time,

SpaceX was still a relatively small company,

only having launched three Falcon 9s to date.

After that rumors were swirling about a Falcon X,

Falcon X Heavy, and Falcon XX rocket

that would be their next mega rockets.

It wouldn't be until 2016

at the International Aeronautical Congress

in Guadalajara, Mexico

that the world would really get a sense

for what SpaceX was actually working on.

And yes, that was that super weird press conference

where everyone asked ridiculous questions.

Well, not everyone.

Hello, Elon, Tim Dodd here,

the Everyday Astronaut with Spaceflight Now.

You show it going into orbit with the 100 passengers

and then refueling it three to five times,

and then doing your Mars injection.

- Right. - Is this the plan,

or is it to have a fully-fueled IBT, or MCT, or whatever,

and then put passengers on board?

Or can you tell me a little bit about that process?

- Yeah.

- The plans Elon showed were properly ludicrous,

maybe even plaid,

something the world had never seen legitimately proposed.

A fully reusable, 12-meter wide, 122-meter tall rocket

with 42 full-flow staged combustion

methane-powered rocket engines on its first stage,

then six vacuum engines

and three more sea level engines on the upper stage,

and advanced carbon composite construction,

and sporting a nutty 300-ton payload capacity.

It was known as the Interplanetary Transportation System.

After 2016 we saw some tweaks year-to-year,

with the biggest change actually being an unbigenning change

when suddenly the rocket shrunk to a nine meters in diameter

and the capability shrunk with it.

Around this time, SpaceX started calling it BFR again

and announced plans to send Japanese billionaire,

Yusaku Maezawo, on a trip around the moon for dearMoon.

But maybe another big change was the decision

to shift away from carbon composite construction

and instead utilize stainless steel.

Then the name Starship finally came into existence.

And, not to be confusing,

the entire system is called Starship,

but so is the upper stage on its own.

The booster is called Super Heavy.

So we can loosely say Starship

meaning Starship and Super Heavy,

but we could also just be talking about the upper stage.

Kind of like how you can point to corn and say,

"Hey look, that's corn."

If it's off the cob and in a bowl,

you'll still call it corn, but when it's on the cob,

you might say it's corn on the cob.

(chuckles) God, you can tell I'm from Iowa, can't you?

In 2019, SpaceX held a press event

in front of a full size Starship mock-up prototype

in Boca Chica later known as Mark 1.

By this point, the design was iterating less and less,

and now the upper stage was to have only two fins

that act like giant air brakes.

Now I already did a video explaining the reasons

why they likely went to two fins instead of three,

and it's a fun video.

But that pretty much gets us up to speed on Starship,

since most of the development

had been behind closed doors and on SpaceX's own terms.

I think now would be a good time

to go through the progress of these two programs,

add up what exactly has been built,

and see if we can get a better sense

of their wildly different design philosophies.

(relaxed music)

So this is a segment I've wanted to do for a while.

Skeptics of Starship

will point to all the blown up test articles

and say, "See, they can't even build a tank,"

while skeptics of SLS say,

"It's been a decade and nothing has happened."

So let's lay out all the hardware that's been built.

This will be pretty comprehensive,

but not a full, complete list of absolutely everything,

but we'll at least list out the major milestone things,

starting with SLS and Orion.

there's quite a lot more hardware

that's been completed and tested than you might think.

So far we've seen over a dozen Orions be used

between Ares 1-X, different abort tests,

mock-ups and drop test units.

There's been a mostly feature complete flight

of a legit Orion capsule in 2014

on top of a Delta IV Heavy for EFT-1.

I was at that mission, and it was absolutely incredible.

There's been a test of a full-size hydrogen tank of SLS

that lasted over five hours at 260% of its structural rating

at Marshall Space Center in 2019.

All of the hardware for the first all-up test

of SLS and Orion for the Artemis 1 mission

is pretty much ready for final assembly.

The core stage is currently on the test stand

preparing to do a full duration static fire,

the five segments of each SRB are ready to be stacked,

the launch abort system is ready,

the actual Orion capsule has finished all of its testing

and is back at Kennedy Space Center

awaiting its upcoming launch around the moon.

The Interim Cryogenic Propulsion Stage

has been ready to go for years,

the Orion service module is ready,

literally all of the hardware for Artemis I is completed

and finishing up testing and then integrations.

In total there's 16 RS-25Ds,

four of which are currently integrated onto the core stage,

and 14 of those RS-25s previously flew on Shuttle missions.

There's enough Solid Rocket booster segments

to make up 16 boosters.

There's also four more RL-10 engines

ready to be used for upper stages.

And now that the manufacturing lines

and practices are in place,

parts for Artemis II are coming together,

including the LOX tank, hydrogen tank, intertank,

forward skirt, engine section,

the pressure vessel for Orion, its service module,

the heat shield, launch abort tower,

and other bits of hardware, too.

And of course, as mentioned,

the RS-25s and booster segments are complete, too.

But that's not all.

Artemis 3 hardware is also coming together already too,

including parts of Orion, the SLS hydrogen tank,

parts of the service module,

and again the engines and solid rocket motors.

This is what's been accomplished and completed

throughout the last decade-ish.

So how's that compared to Starship's progress?

Starship's progress is very different.

The Raptor engine started development around 2012,

and since then, here's a list

of what we've seen built and tested.

To date, there's been over 26 Raptor engines built,

many of which are in pieces now,

and likely only a handful

that are truly flight capable at this point.

But that number is changing rapidly,

as SpaceX has cranked out pretty much all of those

in just 2019 alone.

And if we ignore the progress

and the test articles for anything carbon composite

and/or 12-meter diameter Starship,

again, almost everything we're about to list

was built within the last year.

Starting with Starhopper,

which is the only Starship prototype to really fly,

well on purpose, at least, with two flights,

a 20-meter hop and a 150-meter hop.

Then we saw the Mark 1 full-scale prototype come together.

At the same time, SpaceX was building a similar prototype

in Cocoa, Florida as a way for two different teams

to work on different methods of construction

in a friendly competition.

Mark 2, as it was known, has since been abandoned

and is still just hanging out there.

Then we saw the two teams come together at the end of 2019

to finish and test the Mark 1 prototype,

which failed when testing, as was kind of expected

because they were already working on the next one,

which would be called SN1, and that's when they switched

from the Mark to Serial Number nomenclature.

There's been three subscale pressure test articles

that have tested the welds

and the ability to hold pressure at cryogenic temperatures

around this time, too.

They tested SN1,

which kind of imploded when its bottom fell off.

Then we have SN3, which also failed

due to improper testing procedures.

And, as of the making of this video,

SN4 is already complete

and SN5 is well on its way.

And if I keep trying to update this stupid animation

with all the new parts they're making,

this video will never come out,

because they're just making them so quickly.

So in other words, SpaceX has built and blown up

three times more tanks in the last six months

than SLS has built in the last six years.

And this is where we see the massive, massive differences

in the building, testing, and overall philosophies.

Time to dig into this for a second.

(upbeat music)

By now you've already probably got a really good sense

of the design differences and philosophies

just by seeing how these two programs

have developed over time.

But there's a few things that really, really drill in

just how different they truly are.

So let's start by putting ourselves in NASA's shoes.

NASA, being government funded,

has to do things quite a lot differently

than a private company with private funding,

but perhaps the biggest thing they can't really do

is take big risks.

When building something as massive,

complex and ambitious as SLS,

you really need to account for absolutely everything

before you start sending out the instructions

to the contractors.

If you start telling contractors to start building something

and then something changes in the plan,

all of that work is for naught.

And this compounds when you have dozens of contractors

and government supporting employees

all relying on each other to have their parts done on time.

Imagine if a key part gets delayed a year.

What are the government employees supporting that system

supposed to do?

You can't just lay them off for a year

and then bring them back onto the project,

they're gonna go find new work.

You can't really reassign them to something else.

It's not like a propulsion engineer

is now just going to move over

to the other rocket NASA is currently working on.

There's a lot of inherent costs per year

that are sunk costs in running a program of this scale.

So, although it's inherently less risky and inefficient,

there's also a safety net

for having multiple contractors and space centers

spread throughout the country,

which massively helps make it more appealing to congress.

So, although it is inefficient, it at least does help ensure

the program survival and that it continues to be funded.

And this is especially true when you realize

that it's written into law that the Europa Clipper,

a probe to Jupiter's moon, Europa,

is legally mandated to fly on SLS.

And perhaps most nutty about that fact

is that $250 million has been added to the program

because there won't be an SLS rocket until at least 2025,

despite the probe being ready by 2023.

But in the long run, this law

did help keep a program moving forward and being funded

during what could be very uncertain times

with changing administrations.

Now this obviously isn't ideal at all,

but if you're worried about program survivability

and not just having your entire vision

shift 180 degrees every four to eight years,

doing things like this is just kinda part of the game,

for better or worse.

But don't forget, NASA's budget

is only about half a percent of our national budget,

and the human space flight programs

aren't even half of that.

So in general, the primary philosophy of building SLS

is to plan ahead and take little risks,

because there really isn't much room to fail

when you have to answer to the taxpayers

why their money literally went up in smoke.

Now compare this to Starship.

Starship development is literally

about as blank slate as it gets.

SpaceX started not with detailed blueprints,

but quite literally started

by just learning what questions to ask

and how to frame the constraints

of what their vehicle should do.

SpaceX seems to have wound up on two main objectives.

Be fully and rapidly reusable, and have a capability

large enough to be useful

in getting humans onto other celestial bodies.

That's really about it, and then start to work backwards.

The next most pinned down item

that helps to answer that question

is developing an engine that is efficient

and massively reusable.

Like I talked about in my video

about SpaceX's Raptor engine,

a methane powered full-flow staged combustion cycle engine,

fits the needs of these goals perfectly.

From there on, the whole thing

is pretty much just a giant playground.

Hence, when we saw the sudden pivot

from carbon fiber to stainless steel,

you get a sense of just how important it is

for SpaceX to just start flying

so they have a starting point to iterate on

when you hear Elon explain why it was so important

to make the switch.

- Taking the general approach of,

if a design is taking too long, the design is wrong,

and therefore the design must be modified

to accelerate progress.

- Right.

- One of the most fundamental errors

made in advanced development

is to stick to a design even when it is very complicated

and to not strive to delete parts and processes.

It's incredibly important.

So this is why the switch to steel

was because the advanced carbon fiber was taking too long.

- This is why we're seeing so many random things

happening down there at Boca Chica, Texas

with the development of Starship.

It's why it's kind of silly

to even bother asking about future plans anymore,

which of course I'm as guilty of as anyone. (chuckles)

Because everything depends

on what's going to happen with the current step,

and the step in development after that

will be based on the results of the previous step

and et cetera, et cetera.

It's a similar philosophy

to something known as the agile model

which is standard in software development, which makes sense

because of Elon's original background in software.

Basically, you don't work on step two

until step one is done.

Planning ahead any further

and you're very likely going to have to just undo work.

Now this is quite literally the opposite of SLS,

where everything needs to have an exact plan

because, if you end up building the rocket

three meters shorter than the blueprints, all of a sudden

your entire ground support system will change too,

and by the way, pretty much this exact thing

has basically happened with SLS and its mobile launch tower.

But everything for Starship

is still on the table at the moment.

I mean, we're literally seeing them

build a factory around a rocket

instead of vice versa.

And frankly, this is pretty risky.

But it's also much easier to do,

because SpaceX is so vertically integrated,

meaning changes in decisions

don't have nearly as big of a ripple effect

as the other, more traditional methods.

But just know, we will see more hardware fail.

We will see some setbacks, we will likely see explosions.

But, unlike SLS, not only is it okay to fail,

it's halfway expected as a way to learn and prototype

with lower cost and greater speed.

Elon has said over and over in some way or another,

"Failure is an option here, if things are not failing,

"you are not innovating enough."

This is very similar

to the Soviet Union's design philosophy.

Basically, build something as cheap as possible,

test it out, if it blows up,

see what went wrong, make improvements, repeat.

And it definitely gave them a leg up in the space race

during early development.

So say you blow up a rocket that you built in a month,

oh well, learn from it.

SpaceX will build another rocket in less time

than it'll take NASA to fuel up and test fire the SLS once.

And that's just simply a huge,

huge difference in philosophies.

(relaxed music)

Okay, I think it's time

we really stack these rockets up side by side

to help figure out just how they really compare

when we look at their nuts and bolts.

We've already touched on each vehicle's dimensions,

so here they are again on screen.

For now, we'll compare some initial builds of each rocket,

so the Block 1 and Block 1B of SLS

and the rough-ish version of Starship

as it currently stands.

But definitely keep in mind

that Starship will change (chuckles) a lot,

pretty much every time one gets built

for at least the first dozen or two.

But SLS could also change a bit too if Block 1B goes online.

But while we're at it,

let's throw up the Saturn V and the Falcon Heavy

just so we have some extra perspective

on how these vehicles really compare.

As they stand today, SLS is big, really big,

but Starship will be huge.

Now let's talk engines and their fuels.

Falcon Heavy has 27 sea level Merlin engines

and a single vacuum-optimized Merlin engine

on its upper stage, which all run on RP-1.

Then there's the Saturn V, which had five F1 engines

on its first stage that ran on RP-1,

five J2 engines on the second stage,

and a J2 on the third stage that ran on hydrogen.

As we know, SLS has two SRBs,

four RS-25s running on hydrogen, and the Block 1

has only a single RL-10B2 on its upper stage,

and the Block 1B will have four RL-10s

that all run on hydrogen.

Lastly, Starship has 37 engines

on the Super Heavy booster

and six-ish Raptor on Starship.

This number is very subject to change,

and is relatively easy for SpaceX to do so

because of the small size of the Raptor engine.

Next let's look at their thrust at lift off.

As always, this is pretty fun.

The Falcon Heavy is the baby here at 22.8 meganewtons,

followed by the mighty Saturn V at 35.1,

then the SLS at 39.1,

and lastly, Starship will be the king here

at 72 meganewtons as it currently stands.

Now we've already gone over

some of these rockets' low Earth orbit capabilities,

so let's add SLS and Starship back into this.

Now notice, we are going to be showing

performance for SLS Block 1 and the Block 1B upgrade,

but their low Earth orbit capabilities

are virtually the same since it's the core stage

that pretty much drops them off into orbit.

But now let's show how much mass

they can shoot off to the moon,

otherwise known as a trans-lunar injection or TLI,

since we're talking about lunar missions here anyway.

Quick note, this isn't necessarily

how much a vehicle can put into lunar orbit,

just how much it could shoot off to the moon.

You still need to get into lunar orbit with your spacecraft.

In the case of Orion or Apollo,

that's done with the Service module.

And this is technically a C3 of -0.99 to be exact,

which is a measurement of the characteristic energy

to get to a certain point in space.

Falcon Heavy, when reused,

can sling about nine tons to the moon

if all three cores land downrange on drone ships,

or about 15 tons when expended.

Then we have the Saturn V

that could send 48.6 tons to the moon.

Then, SLS Block 1 can take 27.5 tons,

and the 1B can do up to 43 tons.

Now, you might ask, "How can a more powerful rocket

"get less to the moon than the Saturn V?"

Well, that interim cryogenic propulsion stage

is seriously undersized for this size of rocket.

But oddly, even with the Block 1B

and the four RL-10 powered Exploration Upper Stage,

the SLS can still only send 43 tons to the moon,

so that's shy of what the Saturn V was capable of.

Which, quite frankly, that's kinda baffling to me.

And Starship is a little more confusing

when it comes to TLI.

Starship on its own cannot do a trans-lunar injection.

Because of its massive 120-ton dry mass,

lugging all of that dead weight all the way out the moon

doesn't work out without it being refueled.

Now of course, in-orbit refueling

is 100% part of the plan for Starship.

But we'll talk more about that more

in an upcoming video

where I'm gonna talk about Starship using a kick stage

versus Starship refueling.

So now here's where we're going to go into a deep,

deep rabbit hole, so hold on to your butts.

We're gonna talk price,

and this is not an easy thing to talk about, you'll see why.

And all numbers you'll see are adjusted for 2020 US dollars.

Let's start off with what I'm going to call

the sticker price.

This is the price you could presumably buy a launch.

For now we're kind of ignoring development costs

and just what the invoice would be

for a launch of said rocket.

But we're going to get into the development costs

in a second, but for now, just file these away.

And we're also only going to look at just the rockets,

not the spacecraft like Apollo or Orion.

Starting with Falcon Heavy at around 90 million when reused

and probably around 150 million when expended.

The Saturn V was around 1.2 billion,

SLS Block 1 and the later Block 1B

will be 875 million once production stabilizes.

And Starship, well, uh, Elon claims they can launch

for two million.

But let's assume they can do two million,

but for a while they'd be smart to charge 100 million

until the market catches up.

So let's just throw 100 million out there

as more of a worst case scenario sticker price.

Now with these numbers,

we can do a very baseline dollar to kilogram ratio.

And since we're talking about the moon again,

let's only look at how much it costs

to send one kilogram to the moon on a trans-lunar injection

for each of these vehicles.

Falcon Heavy can get one kilogram to the moon

for around $10,000 whether it's reused or expended.

Then the Saturn V was about $25,600,

SLS Block 1 best case scenario with a stabilized production

is around $31,500, but Block 1B looks quite a bit better

at $20,000 per kilogram.

And lastly, Starship.

Now remember, a single $100 million Starship launch

can't get anything on a translunar injection,

so it's going to take two additional launches to refuel it

at an extra $100 million each

in order to send 156 tons of payload

on a trans-lunar injection,

which would wind up costing about $2,000 per kilogram.

In case you couldn't tell,

we're kind of sandbagging Starship

just in case it's way, way too optimistic.

And even so, it's still by far

the most economical thing on the chart.

But these preliminary costs are taking a lot of assumptions.

They don't really factor in development costs,

and we've still got a lot to cover

on the topic of budgets and cost.

So for now, just file this away,

because in the next video

we'll really chase all the rabbit holes

when it comes to costs.

(upbeat music)

So how did we get here?

How is it that we have

two completely different super duper mega rockets

going online at the same time?

I think the history kind of speaks for itself.

When NASA started working on SLS,

the thought of a rocket like Starship

would've been utterly ludicrous.

I mean, even today, many people think it's insane

and likely to fail.

But Starship is impossible until it's not.

And then, all of a sudden, literally everything changes.

And don't forget, NASA has been working on SLS and Orion

for nearly a decade.

If SpaceX had approached NASA with Starship in 2011,

it would've been like trying to sell a farmer in 1870

a GPS-guided, nine-liter turbodiesel-powered

four-track 8RX 410 John Deere tractor

with an infinitely variable transmission

and 85-cc displacement integrated hydraulic pump

with 227 liters per minute of hydraulic flow,

air conditioned and heated,

10-inch touchscreen displays and digital monitoring

when they were looking to purchase a plow for their horse.

They just simply wouldn't have believed you. (chuckles)

Oh man, I showed my Iowa again, sorry.

And NASA has had the rug pulled out from underneath them

so many times, so many programs getting started,

only to change direction and change hands 100 times

before the program even has a chance to really get going.

So NASA did what they had to do, they took a safe,

conservative route, leaning on existing technologies,

partners, and program funding schemes

to lay out a rocket that would for better or worse

have a hard time being canceled

so they could at least have truly deep space capabilities

for the first time in nearly 50 years.

Because I think that's the biggest shocker in all this.

It's not Starship.

Humanity has Starship coming.

Starship is destined, because frankly it makes sense

to make a fully reusable rocket.

Everyone wants that, everyone wants to do that,

no one thinks that's a bad idea,

and no one thinks it's never, ever, ever going to happen.

But I think the biggest surprise

is that it would be almost 50 years

before there was a rocket

capable of taking humans to the moon after the Saturn V.

If you told that fact

to the last person to walk on the moon, Gene Cernan,

upon his return home in 1972

that no one will have returned to the moon by 2020.

he probably woulda pulled a Buzz Aldrin

and punched you right in the face.

It wasn't until the market shifted

that rocket technology became achievable, not by nations,

but by a small handful of brilliant and plucky individuals

that could rethink everything and open up commercial options

and opportunities that just simply didn't exist before.

I know Elon's life goal is to get to Mars,

but in the meantime, he'll have completely changed

humanity's access to space for the better.

And yes, even when you factor in how much rockets pollute,

because, trust me, I've already done a very,

very long video on that, too,

which is a fascinating topic,

you should definitely have a watch.

In order to get to Mars, you need a fully reusable,

massively capable rocket, and come to find out

that insane proposition just so happens

to completely shift the economics of spaceflight

by orders of magnitude.

I mean, the reason we stopped going to the moon

in the first place was because it was so expensive

and the United States had clearly measured their genitalia

against the Soviet Union,

and that just simply wasn't a sustainable way

to explore the moon.

So, speaking of sustainable ways to explore the moon,

that's what we'll really dive into in my next video

that by happenstance is mostly done already,

so standby and we'll answer, should NASA just cancel SLS

and use Starship and other commercial launchers.

So at the end of the day, in my opinion,

orange rocket good enough for now,

shiny rocket incredible for the very near future.

And we as team space can celebrate the fact

that we even live at a time

where we'll get to have two super mega rockets

go online at roughly the same time.


So what do you think, did you learn anything new?

Did any of your perspectives change?

I know mine did.

Honestly, when I started making this video

and working on the script,

I thought it was a foregone conclusion.

I thought that I knew everything, and come to find out

it was actually pretty humbling

to really go through how all this stuff works

and just kinda do a reality check for myself.

So let me know if you learned anything,

or something shifted in your mind.

And I'm sure the comments are already still full

of SLS versus Starship,

which is kinda what this video's about.

And I'm probably guessing that I really didn't help

to reduce the number of Twitter arguments.

Sorry, Joe Barnard.

I have a quick list of people I need to thank

for helping with this video.

First off, Boca Chica Mary and NasaSpaceFlight

for providing some of these wonderful images

of Starship development.

I'm sure you're already following them,

but in case you haven't, get your butt over there

and follow their work.

Then I need to thank Kimi Talvitie, Caspar Stanley,

and Martian Days, who all have helped provide

some of the beautiful renders you've seen.

So definitely shoot them a follow.

But also a thanks to Declan Murphy from

for helping me come up with some of these numbers

and crunching some stuff.

He started working on a yeet calculator,

which is just awesome.

Thanks to some of the stuff we were working on,

trying to figure out which rockets could do what things.

So definitely check out

and check out his Patreon page

if you wanna help him do the awesome work he's doing.

Speaking of Patreon,

I definitely owe a huge thank you to my patron supporters

who've already heard this video

so many times before it comes out.

They fact check and do a lot of work for me on the backend,

and it's just awesome.

We have such an incredible community,

so thank you guys for all your help.

If you wanna help add your voice, your opinion,

do some fact checking

or just hang out with like-minded space people,

definitely consider becoming a Patreon supporter,

where you'll gain access to our exclusive Subreddit,

our exclusive Discord channel,

and exclusive monthly live streams.


Thank you.

And while you're online, be sure and check out my web store,

because we have really cool merchandise

like Lunar Mission shirts, which, by the way,

you didn't even get to see the back yet.

Check this out.

Now there's actually a little Easter egg here

to this T-shirt.

So notice it says Lunar Mission in this photograph,

but there's actually more to this photograph.

So if you can figure it out,

if you can figure out what else is there

besides Lunar Mission,

not the remove shoes before entering cabin,

but the additional words to Lunar Mission.

If you can figure out what the rest of that says,

go ahead and type that in at checkout for a coupon code,

and you'll get 10% off this T-shirt, so good luck.

We have really cool merchandise,

they're all hand-printed here in the United States,

hand sewn on patches.

We're constantly making new stuff.

Get ready, there's going to be

a lot of really cool new things.

So check back often,

because some of this stuff is so cool

that even Elon Musk wears it, seriously.


Thanks, everybody, that's gonna do it for me.

I'm Tim Dodd, the Everyday Astronaut,

bringing space down to Earth for everyday people.

(upbeat music)

The Description of SLS VS Starship: Why do both rockets exist?!