Elon Musk SpaceX AMA
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I'd quite like to be proven wrong, spaceflight is an area very near and dear to my heart, but from my point of view Musk's reach appears to vastly exceed his grasp.
EDIT: I did enjoy the AMA though, as it provided some interesting insight into their plans for all of this.
>Glass domes and underground Martian tunnels make for some very interesting science fiction, but I'm concerned about the engineering challenges that he seems to be ignoring in favor of his grand statements of intent.
The AMA, and even that specific question was all about the engineering challenges...
>but the amount of press and attention that they get just by saying "we are going to mars" are crazy! Nothing practical to show, i would be more interested in a mission to build up a base at moon first. But hey! This is show business, what we losers can possible know!?
He literally showed images and video of fuel tank and rocket tech that represent novel advances. He has also spilled gallons of ink justifying why Mars is the place to go next.
EDIT: To be clear, I don't think I am quoting lambentonion here, just giving examples of the stuff that made me comment initially
Re: that specific question, I may just have a different view of what constitutes a question on engineering challenges.
That AMA is of exceptional caliber, however, and there are definitely some gems to be found (see [0] and [1], in particular).
The fuel tank and rocket tech represent novel advances in rocket tech that are as-yet untested, afaik. A scaled-down test stand prototype and a prototype of a composite tank are certainly worthy of praise, but they still require an enormous amount of work to turn into a functioning product.
I'd also like to qualify some of my statements here: I don't think _any_ of these challenges are insurmountable. However I think that it would be impossible for all of them to be addressed on the time scale that Musk proposes, for the amount of money he has stated, with the manpower that SpaceX possesses.
[0] https://www.reddit.com/r/spacex/comments/590wi9/i_am_elon_mu...
[1] https://www.reddit.com/r/spacex/comments/590wi9/i_am_elon_mu...
Does the fact that you aren't including any disclaimers in your posts now mean you no longer work for a competitor to SpaceX?
I suppose it might be worth it to keep including the disclaimer, as it'a possible I may be biased in some way that I'm not consciously aware of. Although it bears mentioning that if my former employer made half of SpaceX's promises, I'd be twice as skeptical! So a point in their favor.
I hope I'm not coming off as too much of an asshole in these threads; I really do want to see commercial space flight grow and succeed going forward. It's just that my experience and the conversations I've had with current and former SpaceX employees gives me an unhealthy dose of skepticism regarding a lot of their claims.
Here's one time Reddit was actually able to help SpaceX (!) by reconstructing a corrupt video stream:
https://reddit.com/r/spacex/comments/25xsyt/progress_report_...
Musk has said there will be no screening of the Mars colonists, and that anyone could go. That means someone who's mentally unstable and/or wants to make a name for himself (ala Herostratus[1] or any number of modern publicity-seeking terrorists and murderers) could go and attempt to harm the spacecraft or colony, both of which would be incredibly vulnerable to such intentional attempts at destruction and are guaranteed to get massive publicity were they to be destroyed or even merely attacked.
This could become even more likely if living on Mars long-term actually becomes viable, and people wind up spending decades on there. Some people will likely go stir-crazy and attempt to harm themselves and/or others.
People who are allowed to go live in Antarctica or out in to space are currently screened very carefully to be compatible with each other and able to psychologically withstand the rigors of life there, and the relative isolation. But there will be no such screening for the Mars colonists, according to Musk, and the isolation and danger on Mars will be even worse than it is in Antarctica.
The isolation and danger will be hugely stressful and difficult to deal with over the decades people will live on Mars. I've read that even in Antarctica, people are rotated out within a year or so because of the psychological difficulties of living there, and no one's been in space for much more than a year.
Even if all you do is accept applicants as they apply, that immediately biases the selection process to better informed and connected individuals.
Even if there was such screening or training, that alone won't be enough if despite it someone onboard the spacecraft or in the colony decides to act out anyway.
I really hope someone at SpaceX is seriuously thinking about these issues and coming up with practical solutions, as that's the only hope of preventing some unhinged or politically motivated individuals from turning a promising colonization effort in to a tragedy.
I suspect that will go out the door as soon as a major funding partner demands otherwise, to mitigate potential risk to their investment.
Eventually, sure, the screening will likely become less and less invasive; but at that point we'll have hundreds of people on Mars and the launch/voyage will be routine.
I wouldn't take Musk's word as gospel here.
Check out Robert Zubrin's article, which presents a much more salient critique of SpaceX's current plans than I could [0].
[0] http://www.thenewatlantis.com/publications/colonizing-mars
If you just mean that it's sad that people need this kind of hyperbole to get excited about space, well, different strokes for different folks. You don't need it, they do.
Musk has done incredible stuff already, he has shown multiple prototypes of what they are building. Sure, maybe they will fail, but I don't understand how you can call everything "empty promises".
He promised a orbital rocket landing, he delivered.
He promised a reusable rocket, this he is very close to as a used rocket was already did multiple full duration test fires.
He promised a new engine, he shows this new engine and its first tests.
He actually delivered a prototype of a carbon-fiber tank that literally nobody in the community was expecting.
Will people like you only be happy if there are 1 Million people living on Mars?
It seems to me that you have never read the actual communication and you are just going of on statements by third parties.
"He's done incredible stuff, so take him at his word" is the kind of nearly religious suspension of logic I'm talking about, mixed with equally unfortunate hostility at the "unbelievers" (aka 'people like me'). That you end with a note of incredulity at the notion that I could have arrived at my viewpoints while fully informed walks the fine line between insulting me, and insulting yourself.
>Still, with some corrections, a system using the core concepts Musk laid out could be made attractive — not just as an imaginative concept for the colonization of Mars, but as a means of meeting the nearer-at-hand challenge of enabling human expeditions to the planet.
He then claims that ISRU is impractical due to hypothetical resource constraints.
Zubrin then claims that the Spaceship is a "habitat" that should only go one way. SpaceX has decided that the habitat should be built on Mars from indigenous materials. A one-way Spaceship is vastly more expensive than a reusable one.
Zubrin dismisses fast transit to Mars entirely on the basis of not being a free-return trajectory with a symmetric time span (6 months out, 6 months back). The free return is only if use if the spacecraft is not going to land. The number of failure modes where the Spaceship can't land on Mars but can still manoeuvre into Earth orbit are very small. The Spaceship is designed for aerobraking and landing, not orbital capture.
He then goes on to criticise the four-month express crew transfer as having no payload capacity, when the intent was only to show that rapid crew transfer is possible. The benefit of the shorter trip is less exposure to harmful radiation. The assumption is that sufficient resources already exist on Mars to house and feed the new arrivals.
A multi-component system as proposed by Zubrin with an Earth-Mars transport with separate craft for leaving Earth and landing on Mars adds far more complexity, more moving parts, more ways for things to fail.
The SpaceX monolithic approach us safer simply because there are fewer things that can go wrong.
Zubrin's supposed improvements are to split the Spaceship into propulsion and habitation modules, with the habitation module having its own vacuum engines for Mars intercept and landing, and then some way of splitting those motors away from the habitat upon landing so they can be cannibalised or returned to Earth.
Which is to say, Zubrin has spent so much time evangelising Mars Direct that he no longer considers any other option as valid.
SpaceX are pursuing the engineering goal of sending large payloads to Mars and back to Earth with best use of resources. They want the incremental cost of moving people and things around the solar system to be as low as possible. Zubrin wants a single transit to be as low cost as possible, meaning use of disposable spacecraft, meaning higher costs overall.
But hey! This is show business, what we losers can possible know!?
If you're not an expert in the field it might be worth it to do some research before immediately discounting an idea.
To pick a specific example, he seems to have very little concern for radiation shielding both during the trip to Mars or on the Martian surface. Both of these present incredibly harsh radiation environments for humans, and we need to develop solutions before we even consider sending explorers, let alone colonists.
Though some other comments I think mentioned that it probably wouldn't be too dangerous to allow the occasional stroll through the greenery. Doesn't sound too far fetched if you consider I can choose to hang out at the park without a hat in exchange for an extra dose of UV radiation for the day. Not saying UV is on the same level as cosmic radiation, it's just something to think about :)
The prettiest way to do that are glass domes. The easiest is underground with glass cylinders piping down sunlight.
(Note: The danger of eating Chernobyl's foliage is not that it has been irradiated, but that it has ingested radioactive material. That shouldn't happen with cosmic rays.)
[1]https://www.acs.org/content/acs/en/pressroom/presspacs/2010/...
Most habitation would be underground (hence the mining drones) to reduce radiation exposure.
Overall radiation exposure would be higher, and life expectancy would take a hit, accordingly. This is a trade-off, not a non-starter. I too would like to see a bit more discussion of specifics, but I also don't see this as the Achilles' heel that many would make it.
Also the radiation exposure during flight which would be the worse is equivalent to smoking for two years and dropping it. (I personally thought it was gonna be higher)
Please provide a citation for this. As far as I'm aware, we simply have no idea the kinds of effects that radiation encountered during the flight would have on humans.
The sample size for human exposure to space-based radiation is incredibly small (limited to just the astronauts on the ISS, and even then that is protected by much of the Earth's magnetosphere).
We know a lot about both type of radiation, cosmic and solar. Why know the basic physics, and we know how to prevent it. Both types of radiation have different properties and have different levels of danger, thus need different solutions.
This had been known for a while and solutions are possible. Thus, its not the most important problem in Humans to Mars architecture, as we know much less about reusable rockets and carbon cryo tanks.
something like 50 feet of water would also work for the trip, but water is heavy and you need a lot of it. maybe they can catch a comet, or pull it from the moon. I think there are answers, they're all really expensive answers though.
I find it hard to believe his team have not considered something so obvious. This seems like one of those statements that assumed the experts are a bit stupid. Just because he hasn't specifically mentioned it doesn't mean it is not considered. And sure somethings are probably not considered, but something as obvious as this...
AFAIK no one else within the community would think of saying that.
I'm sure that there are people within SpaceX studying this and taking it into consideration, but my concern is mostly with Musk's cavalier attitude towards individual safety.
>However, we already have data that shows that the accumulation of slow rates of cosmic ray radiation received during long duration spaceflight is not a showstopper for human Mars exploration. GCR dose rates in low Earth orbit are about half those in interplanetary space. Thus, there is a growing number of cosmonauts and astronauts who have already received Mars mission equivalent GCR doses during extended space missions without any radiological casualties.
~http://www.thespacereview.com/article/2749/1
He mentions in a recent speech that the most deleterious effect of time spent in space is related to zero gravity, not radiation - and that can be fixed with resistance training.
We know most of the physics needed to deal with the situation, if we can get equipment to mars. Radiation is a problem, but its not Problem Nr. 1.
1) You imagine what's going on in Elon's head 2) You complain about it on HN 3) You expect other people to care about your fantasy 4) ... 5) ???
There are multiple hard-to-solve problems involved in sending humans to Mars. Complaining that Elon didn't give sufficient weight to your favorite problem in his executive summary is not that interesting.
I'm willing to give him the benefit of the doubt on this one and wait for more details, but at the same time I concede that it's not unreasonable to be wary of claims that the radiation problem "isn't a big deal" from someone planning to sell tickets to Mars. Not everyone has the same notion of what an acceptable risk is.
How practical is it to use an electrically charged or magnetic object between the sun and the spacecraft to deflect particles? Presumably, the farther away it is the less deflection would be necessary, but at some point it would be too far away to effectively mask the whole disk of the sun.
Similarly, you could just use a physical screen. Apparently, things like aluminum don't work very well as shielding because the undesirable particles react with the aluminum and produce more undesirable particles. However, if it were far enough away from the ship, it wouldn't need to block the radiation, it would only need to deflect most of it in a slightly different direction. (Whether the "screen" is on a long tether or whether it's a separate drone-spaceship would be an implementation detail that's not particularly important.)
I assume there's some reason this is impractical, otherwise it would be a solved problem already...
(As for shielding on Mars itself, I'm okay with the idea that humans will spend most of their time underground.)
Musk talks about it because he does not have those constraints.
As for radiation shielding, this has been a topic since the 60s. We know more or less what the risks are, we know the fundamental way to deal with the different type of radiation. The question is how to integrate it in your mission architecture.
He does not spend much talking about this because its not the fundamentally hardest problem that is to solve. The Core Problem to solve is the Transportation Problem. From what he has said about it, he proposed fundamentally the same basic ideas that people have been discussing for many years, and those should work.
1) What RTOS does SpaceX use for the embedded hardware on board? I know they use a lot of Linux, but not for hard real time stuff. What are they running on their microcontrollers?
2) Is it programmed in C, or some other language?
3) Is the embedded equipment on board running on a switched network? If so, does it use TCP/IP or some other protocol?
Anyway, you might find some of your answers in this AMA that the SpaceX software devs did a while back.
https://www.reddit.com/r/IAmA/comments/1853ap/we_are_spacex_...
> Linux is used for everything at SpaceX. The Falcon, Dragon, and Grasshopper vehicles use it for flight control, the ground stations run Linux, as do the developers' desktops. SpaceX is "Linux, Linux, Linux", he said.
We are all a bit scarred after the IAC debacle, perhaps that explains the downvotes.
The atmosphere of Mars, such as it is, is mostly CO2. It takes a lot of effort to get oxygen out of that. Sunlight intensity on Mars is about a quarter of what it is on Earth, so solar panels and plants will have about a quarter of the effectiveness.
There are no easily exploitable resources on Mars. It's going to be more like an Arctic base - you have to bring almost everything.
It reminds me of someone else. I hope Musk gets his pancreas checked often enough.
> Initially, glass panes with carbon fiber frames to build geodesic domes on the surface, plus a lot of miner/tunneling droids. With the latter, you can build out a huge amount of pressurized space for industrial operations and leave the glass domes for green living space
From: https://www.reddit.com/r/spacex/comments/590wi9/i_am_elon_mu...
Still, nothing spurs development like the prospect of a juicy colony contract!
Since it's such a blue-sky project, I'm hoping more to enjoy the design process -- the discussion of science and ideas. I wonder if that process will bring engineers together... or drive them apart?
That's more then brainstorming, thats actually prototype testing of specific sub-components.
I always wondered, why the turn around, and has Musk ever written or said anything about Truax's Sea Dragon[1] concept?