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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Old news (383 comments)

Hmm, now I'm curious. A fighter may have a takeoff weight of say 15000kg. Let's say that the "short lean female" saves 40kg over an "average male". With the other reductions - clothing, oxygen, etc - you probably get down to maybe a 60kg savings. That's a 0,4% reduction in system mass. The rocket equation (applicable here too) probably boosts that up to about a 0,5% benefit in many regards. Still not that much

However, if you can shrink the cockpit , then you're looking at a much bigger advantage - possibly 100-200kg extra weight savings and maybe cutting 5-10% off the total aero drag. That could actually be a big deal - relevantly faster accelerations, top speed, range, etc.

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Psychological issues (383 comments)

There is no "how human societies have been organized". Some societies have had (and even continue to have) near complete segregation of the sexes except for reproductive purposes. Some have had full integration.

And "popular wisdom" is in general stereotype BS. It was "popular wisdom" that said that people of African descent were worthless for anything except manual labor and it's pointless to try to educate a woman, that gays are a social evil that needs to be obliterated, that burning witches is the only way to save the town, and that letting the races mix is tantamount to national suicide.

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:The numbers sound good, but... (383 comments)

Males are not optional. ... Male aggressive creativity would be essential to survival

Strangely not creative enough to hide your gross sexism. Perhaps an aggressive retort would help defend your point?

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Women prefer male bosses (383 comments)

You seriously think you can make a claim credited to a scientific study, and then when you can't show evidence that such a study claiming what you did was ever conducted, suddenly switch to a "but everyone knows" laden with old gender stereotypes and the standard lame appeal to darwin - and think that will fly?

In almost any sentence where people say "Women (verb)..." or "Men (verb)..." and it's about something psychological (as opposed to, say, something involving reproductive organs or a statistical difference in strength / height or the like), 99% of the time it's equally accurate to simply say "People (verb)..." The popular perception of differences between genders (including the effects of both brain structure and hormones) is often vastly different from the statistical reality. Screw Mars and Venus; men and women are from Earth. Psychologically, we're statistically virtually identical in most measures. And in many cases where there are differences that even manage to meet statistical significance, what differences there are may well be artifacts of culture.

How little are most of these "differences"? This set of graphs puts it into perspective.

Again: Either present your supposed "study" or drop the issue.

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Women prefer male bosses (383 comments)

Okay, so I'll take this as "urban legend" until you can find backing.

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Food is not the limiting factor (383 comments)

That is, of course, for a given radiation dose, which is independent of body cross section - which is relevant in real-world scenarios. If we assume an isotropic radiation exposure profile, an average male height of 174cm, an average female height of 161 cm, and asssume an equivalent profile, then a man presents a 17% higher profile to radiation exposurediation exposure, so if a woman has a 50% higher (150%) cancer risk, then it's only 29% higher for a fixed radiation flux per square meter.

However, let's look further at this. Given the smaller size of members of a female crew, you can shrink the spacecraft occupant space by 8% on each axis, or a volumetric decrease of 26%. Mass changes are more difficult to reckon. Life support, food, water, etc is dependent on metabolism, which the article shows is dramatically lower for women in space. Fuel needs are proportional to all other mass issues. Only a few things (such as computers and scientific equipment) don't trace back to crew member size and mass. Regardless, for a given launch weight, it's clear that you can afford the mass of a significantly increased amount of radiation shielding for a female crew due to the weight savings elsewhere, probably easily more than offsetting the cancer risk.

Beyond this, the average US astronaut age is 34, an age well after when most women are done having children (assuming that they even want to have children). Given that the article states the risk is from breast, ovarian, and utirine cancer, I wouldn't be surprised if many would consider full hysterectomy for the ability to travel to Mars.

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Diversity is best (383 comments)

I love the fact that Mars is the only planet known to man that is solely inhabited by robots

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Compelling, but a mix still better... (383 comments)

Despite how radical that statement sounds, it's actually perfectly reasonable for a zero-G environment. They're not only dead weight, they're also in the way and make you require larger accomodations.

Even in Mars's gravity field a legless person would deal quite well, at least inside the facility (picture how easily you could get around without your legs if you suddenly were given 2.5x the arm strength, didn't have your legs weighing you down, and on top of that add in how most double amputees already have good arm strength to begin with). They should be able to "hop" with their arms all the way to a 2 1/2 meter ceiling without trouble, and the full arc would take a good two seconds to come back down. On the moon it'd be even easier. Of course, if they're legless, why would they even need such tall ceilings to begin with?

yesterday
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NASA's HI-SEAS Project Results Suggests a Women-Only Mars Crew

Rei Re:Women prefer male bosses (383 comments)

Citation so we know what you're talking about?

yesterday
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In UK, Internet Trolls Could Face Two Years In Jail

Rei Re:F the UK (482 comments)

I agree. If by "poisoning" they mean people making insolts or dispatching flying penises in Second Life or stuff like that, then it's a bill too far. But if by "poisoning" they mean launching flickering images on an epilepsy forum to try to cause seizures, "doxxing", making legitimate rape and murder threats, etc, then I think it's absolutely justified. All too often is there the assumption that what happens online doesn't warrant enforcement, even if it's something that crosses over into the real world.

Everyone has the right to free speech, but it ceases being free speech when it crosses certain bounds (shouting fire in a crowded theatre, incitement to violence, solicitation of criminal activity, etc). All of these cases are nuanced and require careful balance, but what they should not be is ignored.

2 days ago
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Soda Pop Damages Your Cells' Telomeres

Rei Re:Overly broad? (418 comments)

Exactly what I'm thinking. I respect peer-reviewed research, and take results seriously - preferably consensus positions, but on lesser researched topics, individual studies. But isn't this pretty useless without more details? Is it sugar consumption? Then diet soda doesn't count. Is it phosphate consumption? Then are all kinds of other foods also a threat? Is it caffeine? If so, then coffee is a threat and caffeine-free soda is fine. Is it other lesser ingredients, such as certain flavorants or colorants? What element in their test soda is so harmful that it has such a dramatic effect? Surely it's not all ingredients, or the act of consuming them at once...

2 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

Rei Re:Baby steps (348 comments)

Wrong. I said mass manufacture - you don't have to re-engineer curiosity from scratch and hand-build it every time. And if you can pay to build a super-heavy-lift vehicle, or tons of smaller (but still very large) launches to get your ~100 tonne manned Mars round trip spacecraft into orbit, then you can launch a 100x 889kg curiosity rovers.

You literally can launch about 100 mass-manufactured curiosity-sized rovers for the cost of one manned mission. The scientific bang for your buck is way, way, way higher with robots.

And FYI, if your goal is to be able to help people "live on another planet", then you absolutely should not be supporting wasting money on a trip to Mars on today's way overpriced launch systems. You should be supporting spending it on developing novel systems for orders-of-magnitude reduction of launch prices, be they scramjets, launch loops, coilguns, metastable fuels, nuclear thermal propulsion, or in general insert-your-favorite-potential-cost-reducer-here, so that it doesn't cost an impractical amount of money to send people there. (never mind that we're not even centuries away from being able to recreate a full self-sustainable tech tree on Mars.. see earlier in the thread)

I always find it funny to hear people the same alt-space fanboys complaining vitriolically about how maintaining ISS is a huge waste of money but then insisting that we set up a manned outpost that would cost orders of magnitude more to maintain ;)

2 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

Rei Re:Baby steps (348 comments)

What "all purpose robot"? A robot or person's capabilities are limited by what scientific equipment they have on hand, not by whether they can digest corn or catch a cold. I'm talking about a robot like Curiosity. A person could mass-manufacture and dispatch a hundred Curiosity rovers to every corner of Mars for the cost of one manned mission and would collect dozens of times more data.

3 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

Rei Re:Baby steps (348 comments)

Ref. It took 30 seconds. Please don't ask other people to use Google for you, you're (presumedly) an adult and should be able to manage these sort of things on your own.

But in order to avoid thermalizing your fission fragments the reaction is going to need to be in near-vacuum

The reaction is done in a near vacuum. But that doesn't mean that there's almost no fuel. Fission fragments and neutrons behave totally differently, fission fragments are positively charged and respect Lorenz force, neutrons are neutral and do not, so it's easy to separate the two (as well as from the fuel, which becomes negatively charged and is not moving at relativistic velocities).

These things have been fully simulated, there's nothing unreasonable about them.

but our best neutron mirrors can only get total reflectance at angles of incidence of less than a single degree

I have no clue where this is coming from. Neutron reflectors (more properly thought of as scatterers) can scatter back, and in fact moderators produce a relatively anisotropic thermal neutron flux. The current proposal for a dusty fission fragment reactor involves U235 fuel and a moderator in the shell of the reactor.

3 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

Rei Re:Baby steps (348 comments)

Oh please, be serious. It's humans running the robots who make the decisions. The only benefit a human on Mars has is latency. But that's a really silly benefit, given that there's no urgency to get the data and just travel there takes months and the limiting factor on how much data you'll collect overall is how long your scientific equipment lasts. And no, an astronaut on Mars isn't going to be repairing a broken mass spectrometer or the like, it's a silly concept. And it'd, as noted, be orders of magnitude cheaper just to send a second robot.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

Rei Re:Baby steps (348 comments)

I am correct, look it up if you don't believe me. The energy is primarily in the form of fission fragments. And no, chain reactions work exactly the same, the neutronicity doesn't vary. You're confusing fission fragments and neutrons.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

Rei Re:Power Source (348 comments)

I don't have anything backwards. As far as solar sails go, interplanetary travel is short distance.

The thrust is really, really, really tiny, for really, really, really huge sails.

4 days ago
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White House Wants Ideas For "Bootstrapping a Solar System Civilization"

Rei Re:Power Source (348 comments)

I totally disagree. A dusty fission fragment reactor has been demonstrated using a non-nuclear substitute fuel, which demonstrated proper containment and thermal management. And modelling shows that such a configuration should produce a collimated fission fragment beam. So what's so grossly impractical? Have you come across a paper indicating that it's impractical? Because I sure haven't.

My previous comments apply to NEP

I'm not talking about NEP. I'm talking about generating a RF plasma and funnelling it through a nozzle, like in VASIMR, but with primary heating being from an IR nuclear lightbulb. And even if I wasn't, commentary on conventional nuclear reactors vs. solar is inapplicable when one is talking about totally different type of reactor.

4 days ago

Submissions

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Maldives Denies Russian Claims That Secret Service Kidnapped A Politician's Son

Rei Rei writes  |  about 3 months ago

Rei (128717) writes "As was previously reported here, the Russian government has accused the US Secret Service of kidnapping the son of ultranationalist LDPR MP Valery Seleznev in the Maldives. The son, Roman Seleznev, stands accused of running one of the world's largest carding operations, with others charged in the affair having already been convicted; however, Roman had until recently been considered out of reach in Russia. Now the Maldives has struck back against these claims, insisting that they arrested him on an Interpol Red Notice and transferred him to the US, as they are legally required as an Interpol member state to do. “No outsider came here to conduct an operation,” president Abdulla Yameen stated. “No officials from another country can come here to arrest anyone. The government has the necessary documentation to prove it.”"
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Who's Killing The Electric Car Again?

Rei Rei writes  |  more than 4 years ago

Rei (128717) writes "Aptera Motors is an manufacturer of safe, hyper-efficient, highway-speed electric three-wheelers. Funded by Idealab, Google, and a variety of other sources, they have been working towards making (take your pick): A) one of the ugliest, or B) one of the most beautiful vehicles ever to be mass produced. When they started accepting pre-orders, over 4,000 people from California alone came running with $500 deposits. However, in recent days, the company seems to be imploding, where in the middle of wave after wave of layoffs, disastrous information keeps leaking out. Among the examples: the company's CFO, Laura Marion, was cited by the SEC in 2006 for running an Enron-style accounting scam at Delphi."
Link to Original Source
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McCain taps creationism-proponent as VP pick

Rei Rei writes  |  more than 6 years ago

Rei writes "By now, most people know that senator John McCain has tapped one-term Alaska governor Sarah Palin to be his running mate. While the commentary has ranged from the positive, such as its potential to be a game changer for him, to the negative, such as her involvement in Troopergate, little attention has been paid so far to her views on science. According to the Alaska Daily News, in the 2006 governor's race, Palin was the only candidate to suggest that Intelligent Design should be taught in schools. In contrast to her two opponents, one of whom suggested that such "religious based" lessons belong in a philosophy or sociology class, Palin stated, "Teach both. You know, don't be afraid of information. Healthy debate is so important, and it's so valuable in our schools. I am a proponent of teaching both." In response to the backlash, she later backpedalled and insisted that she would not apply a creationism litmus test to her school board appointees.

Evangelical leaders are reportedly thrilled with her nomination."

Link to Original Source
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Nanosolar delivers high-efficiency thin film cells

Rei Rei writes  |  more than 6 years ago

Rei writes "Thin film photovoltaic systems have been heralded as a way to make solar cells cheap enough for widespread adoption, but have also been criticized for their low efficiency. A number of companies have been working to fix this equation. Now, one of them — Nanosolar, a privately held company with funding from Google's Sergey Brin and Larry Page — has finally shipped their first cells produced in a mass-production environment. Nanosolar's cells boast being the world's first printed thin-film solar cell in a commercial panel product, the world's lowest-cost solar panel (they plan to sell at $0.99/Watt, compared to the current minimum of $4.83/Watt), and the world's highest-current thin-film solar panel (5x the next closest on the market), among other things. Their Panel #2, made available as a collectors item on Ebay with the profits going to charity, has already racked up bids of over $10,000."
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Rei Rei writes  |  more than 7 years ago

Rei writes "Yesterday, Slashdot posted about what appeared to be puddles of water sitting on Mars. Unfortunately, according to the Planetary Society's blog, the authors of the paper didn't even bother to check the context in which the "water" photos were taken. The article notes that one shouldn't trust papers that haven't yet gone through peer review. "The white square shows you where the image comes from. It's in the middle of Opportunity's Burns Cliff panorama, on some of the steepest slopes that Opportunity saw before arriving at Victoria crater! Those can't be puddles — unless the amazing "liquid" that puddles here on Mars in a freezing near-vacuum also has antigravity properties.""
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Rei Rei writes  |  more than 7 years ago

Rei writes "There has been a lot of buzz today over Al Gore: in the wake of revelations that his Tennessee mansion uses 12 to 20 times more energy than usual comes an assault in the New York Times over the accuracy of his film, "An Inconvenient Truth". The article's author quotes a number of scientists who are critical of some of his statements, and describe the film as "alarmism". Quick to the counterpunch is RealClimate.org, which has published a harsh rebuttal suggesting habitual dishonesty and deception of readers on the part of the article's author."
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Rei Rei writes  |  more than 7 years ago

Rei writes "SpaceDaily.com is reporting the failure of a SeaLaunch Zenit-3SL rocket and its payload, leading some to question whether the damage will prove too much for the company. A split-second after separating from the tower, the rocket fell and impacted the platform with a firey explosion. The failure of the Zenit, a privately developed orbital rocket, comes as SpaceX prepares to launch a new Falcon I rocket after its last failed on liftoff after three successive, failed launch attempts. While the news for simpler private suborbital rocketry continues to look rosy, is private orbital rocketry perched on a precipice?"
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Rei Rei writes  |  more than 7 years ago

Rei writes "Today, the prestigious Cambridge Energy Research Associates released a report dismissing the Peak Oil theory, suggesting that world oil production will continue to increase for the next 24 years, and then only level into a plateu. The report, which suggests that world reserves are enough to last 122 years at our current rate of consumption, also blasts Peak Oil theorists for repeatedly making unscientific predictions and then shifting them whenever their predictions fail to materialize."

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