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Comment Re:And, I might start buying more from them again. (Score 1) 115

That is the same reason the wife and I have been using Walmart for our online shopping, as it often has prices the same or less than Amazon, cheaper shipping and as a nice bonus a full 2/3rds of the items we purchased last holiday had a "free ship to store" option with many having same day or next day pickup.

Maybe now that Amazon have lowered the shipping we might do more shopping there...then again Walmart recently lowered their free shipping minimum to $25 and most small items we can get free shipping to our local Walmart so I don't have to come up with a bunch of stuff to put in the cart when I just need a flash stick or MicroSD card.

Comment Re: Great idea... But there is a problem... (Score 1) 232

I'm with a group called Venus Labs; we'll have our first book out later this year. :) Materials compatibility is a big topic therein. Thankfully, there are a lot of polymers that have good resistance to Venus's environmental conditions (particularly fluoropolymers, although minimizing coating fluorine content is important for ISRU because hydrogen fluoride is a lot less common than hydrogen chloride and sulfuric acid - so for example PCTFE or PVF would be preferable to, for an example, FEP). The sulfuric acid mist isn't actually very concentrated from a particle density perspective - visibility is a couple kilometers. The mist is a couple to several dozen grams per cubic meter, depending on the altitude, latitude, time, etc (by comparison, OSHA allows people to breathe up to 1 mg/m for an 8-hour work shift). But it is concentrated from a molar perspective - on Earth, H2SO4 mists self-dilute with atmospheric water vapour.

Comment Re:An allegation has been made. (Score 1) 700

I'm expecting that whoever does this investigation is going to act in the shareholders' best interest, which among other things means not exposing the company to massive liabilities in court. If the investigation supports the allegations, then those responsible are going to get canned.

-jcr

Comment Re: Great idea... But there is a problem... (Score 2) 232

"That book"?

Why Venus? Venus has the most Earthlike environment in the solar system outside Earth. High latitudes in the middle cloud layer have Earthlike temperatures, pressures, gravity, sufficient radiation shielding, ample light, and diverse resources already gas phase and only needing to be run through a scrubber to give you feedstocks (even iron, in the form of iron chlorides - estimated at about 1% of the mass of the sulfuric acid - which, by the way, thermally decomposes in the presence of a catalyst to release water and oxygen). Concerning orbital mechanics, Venus ascent stages are of course harder than Mars, but apart from that, it's in a much more favorable spot concerning orbital mechanics, with a much greater Oberth effect and much more frequent launch windows; it can be easier to get payloads to Mars from Venus than from Earth (and can even get gravity assists from Earth). Beyond the abundant solar power, there's also abundant wind power. Normal Earth air is a lifting gas. Unlike a Mars habitat which is a cramped pressure vessel, a Venus habitat is an expansive, open, bright area, full of plants and life. If you don't like someone, go hang your room elsewhere in the envelope, potentially even hundreds of meters away. Bored? Jump into the safety netting; the scale indoors is so big you can basically do indoor skydiving.

As for learning, Venus has vastly more unknown than Mars. Venus is our twin, and the question as to why it ended up the way it did and Earth didn't is one of the great questions in planetary geology. Venus used to have oceans like Earth. Yet today its surface has become this alien place, a veritable natural refinery that bakes and erodes minerals out of the surface and precipitates them out in the clouds. The whole planetary surface, or nearly so, resurfaced itself about 500 million years ago. We have no idea why. Can Earthlike planets just up and do this? If so that's a very disturbing concept. it has the longest river in the solar system - we have no clue what carved it. The best theories are really weird, like natrocarbonatites - super-rare low-temperature lavas that look like oil, flow like water, and glow crimson at night. It has lightning, but we can't seem to find it. It seems to be the second most volcanically active place in the solar system (after Io) but we've never positively confirmed an eruption. There's a huge amount that our planetary models just can't explain. Why doesn't it have an intrinsic magnetic field? Even with its slow rotation speed, dynamo theory says it should; it doesn't. Where's its mercury? Chemical models say that there should be 3 1/2 orders of more in the clouds than the upper detection limits of the probes thusfar constrained it to. What are the strange radar reflective frosts / snows in the highlands? Pyrite? Galena? Tellurium? There seems to be more than one type, too. I could go on for pages and pages here. And there's vastly more reason to have humans present for exploration on Venus, because given the surface conditions, latency for controlling robotic probes is very important - unlike Mars, where communications "downtime" for rovers just gives them more time to charge in the weak sun. And you don't have to worry about degeneration due to low gravity like you do on Mars.

The surface, while hostile, is absolutely accessible. The Soviets had a lot better success probing the surface of Venus than they had Mars. The basic design is very simple: metal shell. insulation, and a material that absorbs heat through a phase change; it can easily buy you a couple hours. Tech developed by the Soviets in the 1960s. It's been determined that you could actually shoot a hollow titanium sphere at Venus, without any kind of heat shield or parachute, and it'd reach the surface intact; that nice "fluffy" atmosphere goes a long way. On Mars you have to have controlled propulsive landings onto rough terrain with little to slow you down - something that continues to randomly kill landers. The surface air on Venus is dense enough to allow you to dredge minerals off the surface.. You can get off the surface, too, with phase change or bellows balloons. The surface is even accessible for humans, and not just in "submersible"-style vehicles - through atmospheric diving suits like are used for deep sea human diving. NASA was developing such "hard suits" for the Apollo program and a bit after - the AX series. They went with soft suits because they're lighter, but hard suits have better mobility. And more to the point, on Venus with such a suit and a bellows balloon, a person could literally fly - floating up, and gliding down with little wings in controlled flight at up to a couple dozen meters per second.

Comment Re:I'm not surprised. (Score 3, Insightful) 700

I'll go farther: everyone has bad days where they do things they shouldn't do. Especially in matters of the heart and loosely affiliated organs. I'm not a big fan of knee-jerk firing in response to an accusation.

It's the inevitability of this that means an organization needs to be prepared to handle problems like this, and that's the problem here: the organization, not the supervisor. If the atmosphere described here is accurate, then management and HR aren't doing their jobs.

Comment Re: Great idea... But there is a problem... (Score 1) 232

What is the cost of launching a Mars vehicle directly from Earth?

$7k/kg by Falcon Heavy pricing. Would you rather a different launch system?

Insanely high

Not really. But the problem is your "lowering prices" standards involves having to send things into to an entirely different gravity well (consumables), and landed propulsively, so that other different things can then be launched from said gravity well.

And it has diminishing returns

Your proposal, absolutely.

From Earth, there are no diminishing returns whatsoever. Just the opposite - the more you launch, the cheaper it gets per kg.

There is no practical way to launch a large enough manned vehicle for Mars

One: completely and utterly false. There are a huge number of different proposals for this, all of them technologically feasible.

Two: your counterproposal involves doing the same for the moon, and then doing constant resupply so that they can build things that require an entire industrial base there. It's an absurdity.

Let's take a look at the Falcon Heavy heavy lift vehicle [wikipedia.org] which is one of the heaviest available right now. The payload to Mars is about 13,000 kg. That is about the weight of 1 ISS module.

And?

No, seriously, and? Just ignoring that you can launch to LEO, including transfer stages, and this you actually can launch over 50 tonne segments, is your notion that humans can't build things in space? If not, walk outside tonight when the ISS is due to pass overhead, and look up.

The cost per launch is $90m. Want five launches to build it? Ten? Fifty? You're still a fraction of the cost of establishing the sort of industrial infrastructure needed on the moon to support rocket launches, which in turn is still going to cost more than from the Earth due to the cost of said infrastructure's imports.

Have you ever thought why no NASA missions to outer space has been refueld?

You mean like the ISS?

The ISS station gets refueled all the time but not probes. Why is that?

Because it's cheaper to just build things on Earth and launch them, exactly the point I've been trying to get you to understand this whole time. Doing things in space increases the cost, and the further you are from Earth, the greater that cost is. Work in LEO is expensive because everything requires consumables that must be launched (humans in particular). Work on the moon is vastly moreso because it requires vastly more delta-V to get there. You're wanting to do the vast majority of the work at a place where costs make LEO look like a bargain. Work that can't even be done without developing a whole industrial base to begin with.

By your logic, NASA has no plans for Mars either.

Incorrect, and an absurd statement to make. The "Journey To Mars" program is the core of NASA's focus. (If it wasn't, nobody would ever put MOXIE on Mars 2020. ;) )

This is getting absurd. If anyone else wants to talk to this person (who actually goes by the name "UnknowingFool" - almost starting to wonder if this is trolling), go ahead - I'm out.

Comment Re:I'm not surprised. (Score 2) 700

First of all, moderators, while I disagree with this guy's opinion, it's not a troll. It's just an opinion we disagree with. Learn the difference.

That said, making a sexual advance to a subordinate right off the bat is just plain stupid. You don't know each other, and anyone in her position would feel uncomfortable. It's an office, not a bar. People are there to work, and what's more they can't avoid each other. That's why you need professionalism in your job conduct.

HR's response was also stupid. In business you often get into trouble by saying too much, and that's exactly what they did. They could have said, "We've issued a verbal and written reprimand and will be watching this situation closely; let us know if more this kind of thing happens." Instead they had to bring in the fact that this guy was a "high performer", implying at least that this gives him a license ordinary managers don't have. Now I think we can all assume that on some level high performers get leeway that low performers don't. But saying so is stupid. It's pretty much tantamount to a confession that you don't take this seriously.

Then they compound the stupidity by telling her to expect a bad review from this guy because she brought this up. This pretty much is an admission that HR and management countenance unprofessionalism, allowing managers to use employee reviews to pursue personal issues rather than evaluating the employee's contribution to the company.

That's just asinine. If it's false you're undermining employee confidence in the review and performance reward system for no reason. If it's true you should be fixing it, an in the interim keeping your mouth shut.

Now I'd say you should keep your work and personal (e.g. sex) life separate, but I know some companies don't give employees time to have a personal life. If a company does that you're absolutely right, your HR people are going to have a tough time navigating the line between advances and harassment. All the more reason not to be sloppy. If someone in such an environment can't broach the subject with tact, he'd better be prepared to be celibate.

Comment Re: Great idea... But there is a problem... (Score 1) 232

Nowhere did I say that NASA needs to rebuild and entire installation; however, in terms of fuel cost it is much easier to launch from the Earth to the moon then refuel at the moon

Implicit in saying that is the premise that the moon has an industrial base, because you don't make fuel and launch rockets without an industrial base. And an industrial base means dependency chains. And even importing a very small fraction of the amount from Earth to fill gaps in their dependency chains that they launch from the surface would easily price them out of the market. Never mind the absurd capital costs you have to amortize.

Current NASA plans have the moon as a refueling point

NASA has no plans for a lunar refueling point. It is not part of any actively-being-worked-towards timeline. They've posited the concept before, but they've posited a million fanciful things.

Comment Boy, that is a STUPID idea. (Score 5, Informative) 232

Good thing that's not what they're actually doing.

If you read the actual GAO report, it doesn't say the rocket costs twenty-three billion. That's the cost of "the first planned SLS flight, the ground systems for that effort, and the first two Orion flights." In other words the costs to meet certain early program milestones, including costs which should properly be amortized across the lifetime of the rocket and crew vehicle.

The actual per launch cost of just the SLS system is supposed to be about $500 million, or 2% of the $23 billion figure.

That's still a lot of money. Even if you go with expendable costs of half a billion, and billions for the whole mission for sure, well, it's a lot of money just to prove you still have big balls. Not that that's completely unimportant, but I'd like to know what the manned component does for the mission besides make it more complex and expensive and therefore a more impressive demonstration of our manhood.

Comment An allegation has been made. (Score 5, Insightful) 700

And it appears that Uber is investigating said allegation. We don't have enough information to know whether it happened or not. That's what investigations are for.

After the Duke Lacross Lynching and the UVA rape hoax, I'm inclined to reserve judgement until an accusation becomes a lawsuit and is litigated.

-jcr

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