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Comment Re:Moon- not perfect, but has possibilities (Score 1) 295

I mentioned that. The discoveries on lunar water are in consistent (for example, non-detection by Kaguya, disputed detection by Deep impact, criticism of Chandrayaan's detection as not being consistent with solid ice (at best small ice particles), etc. But I do agree that on the balance the evidence is pretty compelling that there are places where ice could be recovered/produced. Even if you take the optimistic view on volatiles (not just water), they're clearly not evenly spread, and generally seem to be (as expected) at significant driving distances from lit regions. Workable? Probably. Ideal? Not really. But hey, it's certainly a better outlook than it was a couple decades ago :) I'll be a lot happier though when we have some ground truth on the subject showing CHONPS all in the same general area ;)

Hey, we're thinking along parallel lines!!

I'm part of a group called Venus Labs that's actually developing the concept further, doing more detailed studies on each component of the concept that Landis presented. :)

Comment Re:The sharing of table scraps economy not viable? (Score 1) 295

So your argument is that Uber is better than a taxi company that employs serial rapists? Does that also mean that Uber will lose that accolade if they ever employ (sorry, contract) a serial rapist?

Actually, my real argument is that while Uber may be shit, taxis are also often shit. Suggesting that Uber is worse than taxis is dumb. The women I know who have been raped by taxi drivers (two of them, now) use Uber because there is at least some accountability and it's convenient.

Comment Re:Its Not If We Could get to the Moon, Its Why? (Score 1) 295

Not exactly. Minimum energy trajectories are really undesirable for humans. Fine for cargo, but you get a lot of time cut off the trip with just a relatively small amount of extra delta-V. Seriously, I recommend running out the numbers for fast Hohmann transfers to Mars - assuming aerocapture, it's a major improvement at little cost.

SpaceX, for one, wants fast transits with ITS. And I don't blame them.

Comment Re:Hydrogen is really useful for going places (Score 1) 295

SpaceX's kerosene is a good decision for putting stuff into low earth orbit compared to hydrogen. When you go farther away than that, the hydrogen advantage kicks in. For Low Lunar Orbit and Mars transfer orbit, hydrogen is very useful.

The problem with going further away on hydrogen is that hydrogen is not generally considered a "storable" propellant; it's very hard to manage boiloff. Mild cryogenics like methane (SpaceX's plan) are easier. It allows you to use the same stage for transfer, entry, and launch burns.

Also, the Falcon heavy will need an extra stage to go much beyond geosynchronous orbit

Why? It's a 3-stager (or if you'd rather not count boosters as full stages, 2 1/2). Designed specifically with Mars missions in mind. 3 stages is a good number for kerolox missions to MTO if the stages have a low mass fraction (like SpaceX's do). You could even do it with 2, although it'd cut your payload.

The SLS solid boosters seem ready now.

They're not. You're confusing test firing with completion.

The big SLS first stage will probably be ready in 2 years.

In your dreams. The smallest variant isn't scheduled to fly for 1 1/2 years, and that's assuming that the schedule doesn't slip. That's Block 1, 70 tonnes. Block 1B (again, assuming no schedule slips) isn't scheduled until 2021 - and that's only 105 tonnes. There's three scheduled launches of Block 1B, the last in 2026. The latter being asteroid redirect, which, well, don't hold your breath ;) There are no scheduled launches of Block 2 (130 tonnes).

You have this weird conception of how far along SLS is. They only even finished the test stand for the tank last month.

Comment Re:The sharing of table scraps economy not viable? (Score 1) 295

Aren't the batteries expensive to replace when they wear out?

They're not cheap, but they're getting cheaper every year.

I'm just saying driving for Uber under their original/current model is unsustainable. Their drivers are thinking "hey this is better than minimum wage!" but these are people who do not understand capital amortization.

Yeah, by the time you can buy a car with poly bushes (automakers hate them like that one simple trick, because they last forever... no, but really, they pretty much do) it'll probably be self-driving. It'll be the automakers' way of reducing fleet maintenance costs — because they will own the fleets.

Comment Re: No Dragon 2 Soft Landing Yet (Score 3, Informative) 295

What, exactly, is the purpose of hanging in the clouds of Venus ?

What, exactly is the purpose of hanging out in the near-vacuum of Mars?
What, exactly, is the purpose of life?

If you don't agree with the merits of the human race becoming a starfaring civilization centuries from now based on investments made today in getting the ball rolling today, I'm not going to debate that with you. But if you agree with that, then the whole point in expanding offworld is to develop into a multiplanetary species, where demand drives down launch costs and we learn, step by step, to make everything that we need in offworld environments and to become adept at the multi-month journeys between planets. At first, it's a sunk cost. With time, it's increasingly supported by trade. And after long periods of time, it brings the immense resources beyond our planet into our grasp.

If you want to talk about economics on Venus, here's a few for you.

  * Power is immensely abundant. Many technologies that we employ are basically energy costs - to pick an example, isotope enrichment. So once the higher marginal capital cost for doing things on Venus becomes overtaken by the greater energy availability, Venus becomes the logical place to conduct such activities.

  * Deuterium levels are ~240 times higher than on Earth. So depending on the level of enrichment you need and the means by which you return it, if you can return goods for somewhere in the "couple thousand to several tens of thousands of dollars per kilogram" range, it's profitable. Deuterium recovery can be rendered an inherent part of nighttime fuel cell power storage, since electrolysis has an excellent enrichment factor.

  * Venus's lavas appear to be highly differentiated, and there's a great degree of chemical weathering and atmospheric processing, which can be another resource enrichment process. So concentrations of high value ores far greater than are found on Earth are not unrealistic. There are a couple dozen elements whose values are worth exporting at realistic launch costs several decades from now.

  * Even simple rocks from offworld have great value (collectors, luxury goods, etc). It's not theoretical - people really do pay huge sums for offworld items. Their value will of course depend first the abundance of their export (if you export 100kg per year, you can sell for 10x more per kg than if you export 10000kg per year, which you can sell for 10x more per kg than if you export 1000000kg per year...). If you're selling in small quantities, the value could be in the millions of dollars per kilogram. Venus's surface atmosphere is dense enough that you can outright dredge loose rocks.

  * The size of the market and sensitivity to export quantity also depends on their aesthetics (aka, moving more from the collectors market into the larger luxury goods market). This means minerals that are durable and aesthetically pleasing. What we've sampled so far of Venus's surface fits that bill - gabbro (sold as "black granite" - large crystalled, dark, hard rock, forms excellent slabs), anorthosite (rare on Earth, often associated with labradorite, which is an iridescent bluish-purple semiprecious to precious mineral), troctolite (rare, olivine (peridot)-rich relative of anorthosite and gabbro - looks like this when cut and polished), etc. It's one thing for your typical sheikh or dotcom millionaire to say "my yacht's countertop is made from the finest tuscan marble." It's another to say "my yacht's countertop is from freaking Venus." You're looking at a very large market in the 4 figure/kg range, a reasonable market in the 5 figure/kg range, and a small but decent market in the 6 figure/kg range.

  * Venus's apparently high levels of repeated differentiation, in conditions very different from Earth, likely mean that some minerals, including gemstones, that are rare or nonexistent on Earth exist there, potentially even abundantly. The gem market on Earth is massive, and always looking for something new to set their gems apart and boost their value. The value per kg of gemstones makes even the most expensive rockets look cheap - a single diamond of a rare type can auction for upwards of the cost of an entire Falcon Heavy launch.

  * On the opposite side of a spectrum, once a colony is "mostly" self-sufficient, it can justify imports just by "telecommuting". If a colony can sustain itself by, say, 80% of people working domestically, with the import-needs of the whole colony averaging out to 5kg per person annually, and a telecommuter's salary can pay for the import of more than 25kg of goods, then the colony is on a whole running cashflow positive just from telecommuting labour.

  * Part of the goal of people like Musk is cost reduction so that travel between planets becomes an option for anyone, including those just looking for the experience. Look at how many people risk their lives and spend a good chunk of $100k every year trying to climb Everest. On Venus you can skydive into hell, to a surface where you can fly, around mountains covered in things like tellurium or pyrite frosts and snows, where cliffs are steeper and higher than Earth's crust can physically support and where riverbeds have been carved by unknown substances, most likely exotic lavas like natrocarbonatites (looks like oil, flows like water, and glows crimson at night). Of course, your habitat itself is big enough to support skydiving indoors. Tourism becomes most definitely an option.

  * Meanwhile, people to whom the concept of living a pioneer life is appealing - making things with your hands, harvesting and processing plants, even things like homemade soaps and paper - can afford to sell their homes and go live that life if they so choose. The overwhelming majority of people won't choose that life; the fraction will be very small. But a very small fraction of billions of people is still a lot of people. A reasonable "budgeting" scheme for a colony to sustain itself would be to require everyone to purchase a round trip ticket and prepay (before each launch window) their share of the colony's imports; if they can't afford their share of the next launch window's imports, then they leave at the next launch window. Also included would be an agreement that they would conduct a share of the colony's labour, with them also making a down payment to cover the costs of bringing in (subsidized) labour if they don't have a job there (or are fired for failure to actually work); so long as they continue to do their job, they only have to cover the cost of their share of the imports. More well-to-do people could just opt to keep paying the labour cost every year so that they don't have to work. By contrast, people who don't have the means to afford a trip on their own could go there for the job opportunities. And there would be a wide range of work - agricultural, food preparation / processing / storage, laboratory, medical / dental, construction, maintenance, manufacturing, refining, remote piloting of surface vehicles, janitorial, and on and on.

Now, concerning space in general: If you think humanity should just wait, or forget about that altogether - you're certainly entitled to that belief. But otherwise...

Comment Re:The sharing of table scraps economy not viable? (Score 1) 295

Also the drivers who run their cars into the ground in exchange for rent/grocery money. They're basically eating their cars.

Just another great place for EVs. No ICE, no transmission. Replace all the suspension bushings with polyurethane when they wear out and they should last about forever.

Comment Re:Turn it off (Score 1) 222

I have no idea how a Windows guy would have solved that.

You can make a Windows live CD (called Windows PE). It's rarely necessary though.

It sounds like the version of Windows you were trying to install was not officially supported by your hardware.

I was installing a purchased copy of Win7 on a machine that came with Win10, because the tools I needed to use (for which I purchased the machine) only run on Win7. Of course, the vendor of said tools didn't bother to document that anywhere.

For your scenario. downloading the drivers onto a USB flash drive is usually the simplest option. In a pinch you can download on your phone and simply connect a USB cable to the computer, or the flash drive to the phone.

As I said in my post above, Windows didn't have drivers for the USB controller. USB was not available.

Comment Re:People without a clue commenting on crypto (Score 1) 193

> If an attacker gets the hash, he can almost certainly recover the password.

How, other than brute force?

Why do you exclude brute force? Brute forcing typical user passwords given a cryptographic hash of them, even salted, and regardless of the hash function used, is very easy. Brute force is exactly the attack I was talking about.

It's best to assume that possession of a hash of a low-entropy secret is equivalent to possession of the low-entropy secret itself.

Comment Re:Why is my car any different than my phone? (Score 3, Insightful) 77

I mean, this is going on during the afternoon commute, so it's an easy guess the drivers ahead of me aren't actually using their Map app on the familiar ride home, and yet Maps knows when there's traffic. So, we're being watched already.

It's not unusual to use one's navigation device to provide notifications of upcoming traffic congestion, so more people may well be using their devices than you imagine.

Comment Re:Not to be a wet blanket... (Score 1) 295

Yes, wake me up when you've recreated Earth's vast diversity of industrial infrastructure on the moon.

Spacecraft are incredibly complex thing, and you're proposing to build them on a place where you're starting with absolutely nothing. And why? To save launch costs? Yes, launch costs are expensive relative to peoples' everyday experience, but they're only a (ever-diminishing) fraction of the cost of a whole mission.

If you're planning to wait until you can outright build entire spacecraft on the moon, you're planning on pushing Mars missions off by many generations. Even the concept that simple raw, bulk sheet metal of even comparable quality (and thus mass) to that available on Earth will be produced on the moon after two decades of high budget dedicated effort straddles the line between "crazy ambitious" and "crazy". Let alone being able to build it into something of relevance with sufficient reliability, and let alone being able to produce it at a rate that, after factoring in consumables that you have to ship from Earth to keep workers alive and all industrial processes running (consumable feedstocks, maintenance, etc) isn't vastly higher than on Earth.

There is absolutely nothing "cost saving" about operating on the moon; it is a huge money sink, and will continue to be so for generations. The same with Mars. You don't go there to save money, you go there as a very long-term investment in the future.

Comment Re: Cue Automakers (Score 1) 54

The automakers have to do that. The rest of us can sell auto hacking tools with impunity as long as they have substantial non-infringing use, and our right to develop them is actually explicitly protected by law (even through reverse engineering.) So the automakers might well be prohibited from giving us the information we need to tune the vehicle, but it's legal for us to sniff the bus while they do it.

Not in California. We have a fucking stupid huge bureaucracy dedicated to making upgrades unaffordable, because the 3000 people who actively race cars are a huge threat to the environment. Fucking stupidities nirvana here where you can't buy a race cam without asking mother may I.

While I do take offense at the CARB equipment restrictions, you can have basically any kind of car you want in California so long as you build it yourself. It smogs as the engine donor. You only have to do a certain percentage of the work yourself.

Comment Re:No Dragon 2 Soft Landing Yet (Score 1) 295

Well, they did produce that huge carbon fiber tank. Which appears to have failed during one of their pressure tanks. Really, building such a huge rocket out of composites is crazy ambitious (if not just crazy), but my hat goes off to them if they can succeed.

They've also made a mini-Raptor that they've started putting through tests. The fact that they've apparently managed those chamber pressures without corrosion problems so far is very impressive.

It occurred to me the other day that they have an interesting potential "halfway" route to ITS, which is that since they clearly plan to have different variants of the spaceship (cargo, crew, tanker), they could start off with the cargo variant and instead of a cargo fairing, have an interstage and use that to boost an elongated Falcon 9 (like the Falcon Heavy central core). So the spaceship would function as a first stage until it got its own booster so that it could function as a second stage. It'd be a perfect testbed for their new technologies (same construction style and engines as the booster, just smaller), while at the same time boosting SpaceX's launch capabilities into the super-heavy range. They'd want to use more atmosphere-optimized nozzles, but apart from that... it's already designed to handle much greater heat loads as well as full propulsive landings.

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