Nothing wrong with a piece of fiction with laughably bad science on almost every page. If someone gets a kick out of the book, then it's met its purpose. But when the author gets treated as a "Mars expert" due to his his "hard sci fi" novel, that's where I start having a problem.

We should colonize Jupiter by resurrecting the dead there.

Why would you build a moonbase for a radiotelescope or gravity wave detector? What's the argument for dropping it into a gravity well (where it can be exposed to moonquakes and moon dust) and having people operate it when you can just have it unmanned and in space (Earth-Moon L2 for a radiotelescope, Earth-Sun L5 for a gravity wave detector) at orders of magnitude less cost and far greater effectiveness?

Every one of these sort of proposals just screams "I'm an excuse that was made up solely to give us a reason to go back to the moon". The most glaring is surely 3He mining, of course ;)

We see the propulsion breakthroughs right now - there's a wide range of propulsion systems possible with current technology. Unfortunately, the turnaround on these sort of things is measured in decades (generally with a number well over "1"). And if it has any form of the word "nuclear" in the title, multiply the average time from conception to deployment by a large number.

Nobody of course is requiring rockets to be our long-term future. I have a soft spot for the Loftstrom loop concept, for example (aka, a track that holds itself up via the centrifugal force of a rapidly spinning rotor magnetically suspended in a vacuum inside it). Way more efficient and high throughput than a space elevator and requiring no unobtanium.

It would of course not make fuel cheap until we can learn to mine cheaply in space. And we're not even 1% to that stage. You have to pretty much relearn how to do everything you take for granted on Earth in space. Look at Philae just attempting to softly touch down at very low speeds - it had four different ways to try to stop it from bouncing (shock absorbers, ice screws, harpoon, counter-force rocket), and it still bounced way off and ended up in some rocks somewhere. And you're picturing setting up a whole refinery there? Yes, some day. But that day is not close.

The radiation issue is a big one that a lot of people downplay (they forget that the only reason the Apollo astronauts got away with as little shielding as they did was that their missions were on the order of a week or so long - and even still, they would have been in bad shape if a solar storm had hit. As it was they reported seeing regular flashes of light from cosmic rays impacting their retinas.

There've been a number of proposals for how to deal with shielding. One is to build a mini-magnetosphere around the spacecraft; my last reading on the subject was that it would be a realistic way to deflect most solar radiation but not GCR. You still really need physical shielding (which is a complex topic... beta and gamma are blocked by heavy metals far better than they are by light materials, but neutrons need to be moderated down to be stopped effectively, which means light, high scattering cross section elements like hydrogen; heavy ions tend to multiply high energy neutrons. And to make matters worse, forms of radiation switch around - betas kick off gammas due to bremmstrahlung, gammas can kick off photoneutrons or betas, betas can kick off neutrons too, neutron capture kicks off gammas, transmuted elements decay releasing gamma, beta, positrons, alphas, sometimes neutrons... It's really tough.

Most proposals call for using fuel, water, oxygen, etc as part (but not all) of the shielding - it's particularly good against neutrons, as all of these things are generally composed of CHON, all of which are good moderators (especially the hydrogen). A common proposal is to have the heaviest shielding around the beds, as you get better bang for your kilogram that way. I've pondered a more advanced version of that, having significantly more fuel / water / etc tankage space than you need (the extra mass would be part of your shielding anyway, so it's not really a "penalty") and having a computer system intelligently pump it around to where people are at any given point in time and where the sun is / what the current solar radiation flux is / etc. I wouldn't be surprised if you could cut the radiation dose to less than half in that manner, possibly a lot less. You'd need durable, reliable pumps, of course.

Are you kidding? I can't help but picture the MST3K characters ribbing it the whole time.

The main character is a "scientist" who doesn't use a single scientific term, instead using 50s pop-sci-fi style terms like "Oxygenator". I mean, here we have a botanist on Mars who doesn't even know the word "regolith" or understand why you'd have solar panels tilted at a particular angle. But don't worry, the book is full of such award-winning prose as phrases like "My asshole is doing as much to keep me alive as my brain". Seriously, it reads like a 13 year old boy.

But that's minor compared to how on pretty much every page we have Weir demonstrating his complete lack of knowledge of even the most basic aspects of every field of science he covers. Here, let's just pull up a random one:

Not because of the perfect landing, but because he left so much fuel behind. Hundreds of liters of unused Hydrazine. Each molecule of Hydrazine has four hydrogen atoms in it. So each liter of Hydrazine has enough hydrogen for *two* liters of water

High school chemistry, anyone? (Morbo Voice) Stoichiometry Does Not Work That Way! Weir again and again mixes up volume, mass, and moles. (For anyone not seeing it yet: hydrazine is 1,021g/cm^3, hydrogen makes up 12,5% of the mass, or 0,128 g/cm^3; water under STP conditions is 1 g/cm^3 and hydrogen makes up 11% of its mass, or 0,11 g/cm^3. 1 liter of hydrazine gives you 1,16 liters of water under STP conditions, not 2).

Here, let's grab another one of these from just a couple pages earlier:

"Once I get that hooked up to the Hab's power, it'll give me half a liter of liquid CO2 per hour, indefinitely. After 5 days it'll have made 125L of CO2, which will make 125L of O2 after I feed it through the Oxygenator."

Brilliant - not only do we have him once again confusing volume and moles, but we also have "liquid CO2", meaning that for some reason on a planet where a mere shiny bucket will hold frozen CO2 indefinitely, they've decided for no apparent reason to store it as a superfluid in heavy pressurized tanks at dozens to hundreds of atmospheres and elevated temperatures.

Oh, here's a great one: at one point he starts a diary entry by noting that he's now hiding out in a rover because he screwed up and didn't notice that his hydrogen levels in his habitat were climbing and his oxygen levels were dropping over the course of many days until he checked a meter. How much? The hydrogen went up to 64% and the oxygen levels to 9%. Really, the high squeaky voice didn't clue you in? The anoxic unconsciousness didn't clue you in? *Facepalm* Did this guy not get *anyone* to proofread?

The most mind-bogglingly glaringly bad stuff is of course the plants. As we all know, the sun is an incredibly energetic source. Look at the light in your living room for a few seconds. Notice how you're not blind. Now try it with the sun. Yeah, there's a bit of a difference. WIth the sun high overhead on a clear day the ground on Earth receives about 1000 W/m^2 of light energy. Now picture the brightest CFL you can find on the market - maybe one of those giant 40-watters? To match the light output of the noon sun would take 150 to 200 of them per square meter. Even taking into account angles, night, clouds, etc, it's a ton of energy. To grow the couple hundred meters of potatoes to feed a person? Well, you do the math.

So how does our hero plan to grow his plants? Here's Wier's entire justification

Also, the internal lights will provide plenty of 'sunlight''.

That's it. That's his entire justification on how he plans to provide enough light for his potatoes - normal interior lighting powered by a little solar farm on a dusty planet that receives half the light of Earth. Not even normal yields of potatoes, but super yields of potatoes! In regolith that he does nothing to remove the perchlorates or salts from (never mind that he does nothing to shield his electronics in his 100% ventilation-free canister from the humidity which he describes as raining down). And with Weir's humorously bad misunderstanding understanding of gardening we get his interpretation of potato mounding (aka, packing up soil around potatoes once they get to a large enough size to keep them focused on storing starch rather than going to flower):

Also, as their flowering bodies breach the surface, I can replant them deeper, then plant younger plants above them.

You see, the entire part of the potato plant that breaches the surface is merely a "flowering body". You can reuse space just by planting plants successively on top of each other like cordwood! Trust me, I'm a botanist!

Seriously, this thing is MST3K in book form. Hopefully the movie won't be this terrible. Or maybe it'd be best if it was...

Have you actually demonstrated that the higher-level languages you are more familiar with just can not possibly do the job? And keep in mind both RAM and disk are cheap, so "just add more" may work if saving space is your motivation for "granular control".

Whip up a testbed in the higher-level languages you are more familiar with to simulate a load test, and see what sort of performance you get. Zero bells/whistles, just "how much of data that vaguely resembles what I'll be seeing can I shove through the pipe.

If that shows you don't get good enough performance, then try one of the tools that will generate a native binary from the higher-level language, and see if that is good enough.

Often our intuition of what can be done with these systems is off by several orders of magnitude. So make sure you really need it before you go all-native, especially because you're less familiar with all-native. For example, latency over a typical Internet connection means you'll be network-bound no matter what language you write it in, so write it in whatever you're most comfortable with.

Also, if there's particular operations that are really the bottleneck, consider writing the rest of the program in a higher level language, and writing the bottleneck in C or C++. All the high-level languages have some sort of native interface.

It's believed to be the same reason Titan does (just on a much smaller scale) - photocatalysis of methane ice into a mixture of more complicated hydrocarbons (collectively called "tholins").

Which is why you combine the chroma data from MVIC with the luminance data from LORRI. When you don't have both of the same image then you turn the chroma data into a sphere map and generate the appropriate chroma data to map over your luminance data.

Only if they make the vulnerabilities known to the AV makers and (after a suitable period) to the general public so as to ensure that the US/UK populations are protected.

If they can crack it, so can other groups.

C++ lets you have just as much control over the code as C. The key difference is that it doesn't make you memory manage your objects every time, when 99.99% doing that is irrelevant toward performance and only serves as a common route to introduce bugs.

It's not 13bout knowing ex13ctly which register 13 is stored in, r13ther underst13nding how the compiler optimizes 13n 13lgorithm...

Ugh, d13mmit R13ndall...

"Smart pointers" are great -- if you don't care about performance (in which case, why are you not using Java?).

Since when does Java's performance even come close to C++'s in benchmarks? C++ performance is generally very close to that of C's, and in some cases exceeds it (example: qsort vs. std::sort - C++'s use of templating allows for inlining of the sort function code)

Smart pointers have very, very little overhead. The worst is std::shared_ptr, and it's still only adding a reference counter, and that's only used on pointer copy and deletion. And if you have a use case that requires std::shared pointer as your smart pointer of choice, then this is counting that you'd have to be doing anyway in some form or another.

  From the benchmarks I've seen, most people see about an additional 5%-ish overhead in debug mode with std::shared_ptr vs. raw pointers in pointer-heavy code. In a release build there's generally no measurable effect (the difference being, in debug mode it can't inline the dereferences).