
Don’t stage off Starship - davedx
https://caseyhandmer.wordpress.com/2020/02/15/dont-stage-off-starship/
======
_Microft
If you are still unsure about the scale of SpaceX' plans for Mars, here is a
very concise summary by Robert Zubrin (president of the Mars Society):

 _It 's not Apollo. It's D-Day._

It is from an interview with Zubrin who, among other things, discussed mini-
Starship with Elon Musk at the Boca Chica job day recently. It can be found
here [0], with an automated transcription at [1]. Discussed in /r/spacex at
[2].

[0]
[https://www.thespaceshow.com/show/11-feb-2020/broadcast-3459...](https://www.thespaceshow.com/show/11-feb-2020/broadcast-3459-dr.-robert-
zubrin)

[1] [https://hastebin.com/raw/ozimiqenop](https://hastebin.com/raw/ozimiqenop)

[2]
[https://old.reddit.com/r/spacex/comments/f34fqm/zubrin_share...](https://old.reddit.com/r/spacex/comments/f34fqm/zubrin_shares_new_info_about_starship/)

------
mechhacker
This is by far the most interesting aviation/rocketry development I've ever
seen. After watching the two Falcon 9 lower stages come back simultaneously
from the first Falcon Heavy launch, I realized how different things were going
to be.

Starship, even if Musk is off by quite a large factor on the cost to launch,
is still going to be extremely cheap to fly compared to everything else out
there.

Other people copycatting the ideas off of Starship will drastically improve
the space industry costs, regardless if the Mars venture is successful or not
(and I want it to be). This will literally put us in a different era. It
wouldn't surprise me if Starship spins off other industries for vehicles not
focused on Mars, but elsewhere in the solar system, or based on much longer
space voyages.

The next hurdle for deep space, aside from shielding, will be power. Lower
solar flux in deep space and the interest to save weight will likely see the
use of more nuclear power.

Regardless, I'm much more hopeful about the space industry that I was in early
February, 2003...

~~~
moneytide1
> The next hurdle for deep space, aside from shielding,

Zinc Bromide for radiation protection?

~~~
mechhacker
Probably not. It looks like that's primarily for gamma. In space, cosmic rays
are much much more powerful and catastrophic for cells.

Water is actually probably the best shield, because you'll need it to support
humans along the way. Gamma still is a risk but I think the concern has mainly
been higher speed subatomic particles.

Anything with heavy nuclei actually produces significant and also highly
damaging secondary radiation when hit by fast moving, heavy nuclei, cosmic
rays.

Another interesting thing: Apollo astronauts could see sparkles in their eyes
from the radiation effects of getting hit by cosmic rays travelling through
their skulls.

[https://en.m.wikipedia.org/wiki/Cosmic_ray_visual_phenomena](https://en.m.wikipedia.org/wiki/Cosmic_ray_visual_phenomena)

~~~
moneytide1
< sparkles in their eyes

Does the iron core of Earth imply magnetic repellent of the sight of these
Cosmic ray retina inducing sparkles?

~~~
mechhacker
No, the atmosphere blocks almost all of it. If it weren't for that, we'd be
hit constantly. Their influence on weather/cloud formation is an active area
of research [https://home.cern/news/news/experiments/cosmic-rays-
clouds](https://home.cern/news/news/experiments/cosmic-rays-clouds)

~~~
pmontra
I stood by this cosmic trays detector [1] in a station of the metro of Naples,
Italy, for a few minutes. I saw quite a few cosmic rays passing through the
detector.

[1] [https://www.researchitaly.it/en/news/surprise-in-naples-
subw...](https://www.researchitaly.it/en/news/surprise-in-naples-subway-there-
is-an-infn-cosmic-ray-detector/)

------
GuB-42
When talking about big rockets, it is hard not to talk about Sea Dragon. It
was a rocket where the entire design is based on the "bigger is better"
philosophy.

The design was simple. No need for lightweight, high-tech materials, because
it is big. No need for highly efficient high pressure engines, just make one
that is bigger. That thing would have dwarved the Saturn V. The name "Sea
Dragon" comes from the fact it would have been launched from the sea, it would
have been too big for a ground-based launchpad. It would have been built in a
shipyard like a submarine that can stand upright.

[https://en.m.wikipedia.org/wiki/Sea_Dragon_(rocket)](https://en.m.wikipedia.org/wiki/Sea_Dragon_\(rocket\))

~~~
ekianjo
The Orion interplanetary ship would also have been huge - it was planned to be
able to reach Jupiter:
[https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...](https://en.m.wikipedia.org/wiki/Project_Orion_\(nuclear_propulsion\))

~~~
api
An early draft of 2001 A Space Odyssey had Discovery as an Orion, but
apparently Kubrick having just done Dr. Strangelove didn't want to do another
film with nukes.

------
ppaattrriicckk
Personally I think it'd be interesting to compare the expected price/weight to
how much it cost to cross the Atlantic back in the 1600s. Does anyone happen
to have any good references for goods/people crossing back then?

For instance, one person writes on Quora[0] that between 1600 and 1800 one
could cross the Atlantic from Europe by becoming an indentured servant,
working 4-7 years for someone. By looking at the average US income, this
corresponds to roughly $2-300,000 per one-way "ticket".

This is somewhat comparable to Musk's aspirational price for a one-way ticket
to Mars, no?

On another note, I'm sure there were discussions back then about why bother to
spend months crossing the Atlantic..!

[0] [https://www.quora.com/How-much-did-it-cost-in-
today%E2%80%99...](https://www.quora.com/How-much-did-it-cost-in-
today%E2%80%99s-currency-to-travel-from-America-to-London-in-
the-1600s-the-1700s-and-the-1800s)

~~~
setr
I imagine indentured servitude path should be dramatically more expensive by
the end of it than paying straight up -- it's like taking money from a loan
shark; it's not actually a good deal -- but you don't have the resources to
get anything better.

I imagine the actual cost of buying a ticket would probably be like 50÷ the
cost of indentured servitude

~~~
rbanffy
> like taking money from a loan shark

A loan shark that owns the air you breathe.

~~~
setr
Yes, a bad deal. But if it's the only offer on the table...

------
MayeulC
> while storage tanks can be built from local materials

Just use the starships themselves. Actually,to further reduce cost, I would
design starship to be useable as a Mars habitat: even fuel tanks could
conceivably be converted into living quarters,I guess. Further the efficiency
by recycling other parts of the starship as building materials.

Also, most of the reasoning in this article revolves around power plant mass.
I wonder how a nuclear power plant would affect the outcome.

~~~
sp332
The trouble is that the Starships need to refuel very quickly after landing to
hit their return launch window. If you need to generate all the fuel right
then, you need a much larger fuel plant. If you can store the fuel ahead of
time,before the Starship has arrived, you can use a much smaller fuel plant,
but you need storage space.

~~~
fit2rule
You build a version of Starship which produces fuel. You launch a fleet of
them to Mars and have them operate for a year or so.

Then, you send the human-carrying version.

I think the way this is going to work, is when there are 1000 Starships on the
surface, some of them with workshops, some with power plants, others with
science labs, human quarters, and so on .. and they land in a big field.

Humans arrive, string them all together.

~~~
projektfu
Similar to the approach seen in "Red Mars" by Kim Stanley Robinson.

------
rbanffy
Since it seems we are on the verge of having an off-planet colony, I'd like to
launch a couple questions:

1- What are the colonists' fundamental rights and who protects them?

2- Under what jurisdiction will they be?

3- Who owns the air?

4- If someone can't pay for their air or food, what happens?

~~~
aguyfromnb
> _Since it seems we are on the verge of having an off-planet colony_

Has SpaceX even had a successful manned space flight yet? I don't think we're
quite on the "verge" of colonizing space...

~~~
maccam94
> Has SpaceX even had a successful manned space flight yet?

That flight will likely happen in the next quarter.

Meanwhile, while SpaceX has been wading through NASA design reviews and red
tape (some of which is probably good for them!) for Falcon 9 + Crew Dragon,
they've been hard at work on this next-gen rocket for years (the engines since
2009, the rocket itself since 2014). We will likely see a SpaceX Starship
reach Low-Earth Orbit within a year, so it's time to start considering what
other requirements for getting to Mars might take longer to build.

------
ben_w
> Synthesizing that much fuel would require about 1 MW of electricity for 500
> days, requiring in turn 5 hectares of solar panels. Per Starship, per launch
> window. At 50 kg/kWe, the solar farm would weigh 50 T.

Given those power and mass requirements, would it make sense to deploy the PV
in earth orbit and use it to power an ion drive? Those things need a lot of
electricity to be useful, but 1 MW _is_ a lot of electricity — not the 200 MW
for the VASIMR 39-days-to Mars proposal, I’m still thinking of a standard
“slow” journey, but this could also mean only one LEO refuel (for powered
landing) required.

------
credit_guy
Two aspects in favor of mini-starships

1\. economies of scale: if you manufacture 12 engines smaller by a factor of
10, the total manufacturing cost is not going to be 20% higher, but most
likely 2-3 times lower.

2\. engineering knowledge: more smaller engines means more engineers. Some of
whom would leave to start their own startups, or to join Blue Origin, or
Skunkworks, or some other aerospace company. That's not necessarily good for
SpaceX, but it's good for humankind. Maybe some would go and fix Boeing's
problems :)

~~~
tigershark
Yeah, right, it must be a child game to scale by an order of magnitude the
only full flow engine that ever flew in Human history...

------
russdill
This seems to completely miss the point of the Starship architecture. With
orbital refueling, staging as discussed in the article, or a smaller Starship
isn't something that would provide a big savings anyway.

Big Starship or small Starship, you get the same Delta-V assuming both are
fully fueled. In fact, you'd probably get more Delta-V out of a large Starship
since you might be able to get a better mass fraction.

------
altcognito
The 5 million per starship must be the cargo ship only. The engines alone are
going to be half that cost.

~~~
rtsil
I assume that's the cost when taking into account the reuses, not the
construction cost.

~~~
nkoren
Your assumption is totally reasonable, but wrong. That's the construction cost
Musk has said he's aiming for.

------
ForHackernews
Is 'Starship' even a real thing? Last I heard, it was an empty stainless steel
can ('aerodynamic model') that blew over in a strong wind. Has that changed?
Are they actually going to try and make this a real launch vehicle?

~~~
maccam94
The Starship Hopper flew a couple hundred meters up into the air using the new
Raptor engine, hovered, and then landed. A full size prototype had a fuel tank
fail a pressure test due to some bad welding. The most recent fuel tank
pressure test succeeded, so it's looking like a 20km altitude test flight will
happen in the next few months.

------
smoyer
I have a few interesting questions ... to be fair, I've done no science or
math to make a conclusion but there would certainly be a sense of irony
involved.

1\. Could the green-house gases produced to launch a civilization to Mars be
the final straw that breaks our eco-system's back?

2\. What are the moral implications of terra-forming Mars and moving a small
population there, knowing that the population remaining on Earth is doomed?

3\. If you're willing to allow an epic depopulation of the Earth, why not stay
here and let it happen?

4\. If any of the above are true, why would you expect the (current) larger
population of the Earth to fund the colonization of Mars?

I realize this is a very dystopian view ... and that I read/watch too much
science fiction, but if this is a novel (or a Netflix original), the Mars
population moves back to Earth after it's "recovered"

EDIT: I'm not against the StarShip, SpaceX or Musk at all - in fact I'm a big
fan as I was in elementary school during the Apollo missions and believe that
SpaceX in particular has reinvigorated the passion for engineering and
tackling big problems. This is only a Gedankenerfahrung.

~~~
PaulHoule
I want to use a Starship to put a solar sail factory on an NEO and send the
sails to Earth-Moon L1 to block sunlight to buy us some time.

If you think you can change human nature fast enough to curb climate change
you should think again; introduce new energy sources that are cheaper than
fossil fuels and you can make them.obsolete.

~~~
chr1
"buying some time" would be the most underwhelming use of such a technology.
If you are putting large enough sunshade to change the climate, you can use it
to actually control the weather, make sahara green, make siberia warm, melt
greenland ice sheet in controlled way moving it to antarctic.

~~~
_ph_
Making the Sahara green is a good idea, Siberia warm, much less so. Actually
the thawing of the perma frost is currently one big danger, as it would
release a massive amount of greenhous gases (mostly methane).

~~~
chr1
You would do it in a controlled manner so that the amount of released gases
from arctic is compensated by gases absorbed by greening deserts.

------
drenginian
Im no less a science fiction fan than the next person but the whole “colonize
Mars” thing is stupid and wasteful and arrogant and really pounds the message
that billionaires are deeply deeply out of touch with the rest of society.

Not only will colonizing Mars never work, there’s no reason at all to want to.
What a dead, barren place.

And in the meantime back down to earth people are really starting to care
about inequality. Meanwhile billionaires pour resources into childish flights
of fancy when the world is literally burning.

Ugh. I really think billionaires have a place in our society but these sorts
of projects make me understand why others question whether some people should
have such huge control of resources.

No one is even visiting Mars, let alone colonizing it.

~~~
snowwrestler
I think you’ll get downvoted but I largely agree with you about the futility
of the exercise. The complexity of the Earth’s system for sustaining life
still far exceeds our understanding, and I think going to Mars will at best
turn out to be a powerful way to learn that we cannot replicate it.

The typical moral justification is that the Earth may be threatened and so it
would be prudent to have some humans somewhere else in the solar system.

Well the number one threat to Earth is an impact event. If we can hypothesize
a rapidly growing lift capacity, why not use that mass budget to develop a
solar-system-wide system for detecting and if necessary altering the
trajectory of potential impacting objects? It would be WAY better to protect
the Earth than any other backup plan.

The other big threat to the Earth would be a fast gamma ray burst but that
would very likely get Mars and any other human colony as well.

The reality is that people want to go to Mars for the same reason people want
to go climb mountains: because it is there. Our economic system provides a
very few people with the resources to pursue those dreams. Whether that takes
away from everyone else depends on how you think about the economy—to what
extent you believe it is zero-sum.

Personally I think we should go to Mars for the simple purpose of going—I like
exploration and climbing mountains too—but not fool ourselves about
establishing a new human society there. To me it’s like say let’s establish a
new human society on the summit of Everest. Which would be way easier than
doing so on Mars, by the way!

~~~
samatman
> _Well the number one threat to Earth is an impact event. If we can
> hypothesize a rapidly growing lift capacity, why not use that mass budget to
> develop a solar-system-wide system for detecting and if necessary altering
> the trajectory of potential impacting objects? It would be WAY better to
> protect the Earth than any other backup plan._

Detection is a solved problem.

Altering the trajectory of an asteroid requires a large amount of lifting
capacity to be available on relatively short notice. That is, it has to
already exist when the crisis is identified.

Congratulations. You've identified a positive externality of Starship.

~~~
disambiguously
Conversely, of course, the trajectory of a non-threatening near-Earth asteroid
can be known well in advance, but there’s no obviously benign reason for
anyone to bring a lot of delta-v to one.

So having a steady traffic in commercial heavy lift could be a positive
externality as well, for whoever wants to find a close-call asteroid that has
been recently marked as 100% safe and give it a little nudge.

~~~
samatman
Making it easier for mustache-twirling supervillains to destroy Earth is not a
concern of mine, personally.

Weaponizing smallpox and distributing it in major airports is the lower bound
of effort. Anything that exceeds this is not worth worrying about.

