Another reason: assuming there is good clock synchronization between the data feeds of the two sites, you should be able to use their separation to determine from where in the galaxy the wave came from. (With two sites, you can only narrow down the location so far. Three sites should provide a good fix; N sites would be that much better.)
How well do these systems work when their feedstock of CO2 is less than 0.5% pure (i.e. air)?
There are places where the concentration is much higher. For instance, the smokestacks utility-scale, fossil-fueled electrical generators. For instance, there are a variety of large coal plants out in the Arizona and New Mexico deserts, which also have abundant solar (PV and thermal) resources. It may seem a bit strange to co-locate a liquid fuels synthesis plant, hopefully run on variable renewable energy, next to a base-load coal-fired plant, but they each have their uses in the vast landscape of energy supply and demand.
The dream of having a farm with solar panels, converting water to hydrogen to store in tanks in the ground is a cool dream. You can then use that hydrogen to power your car or heat your home.
It is a cool dream, but handling liquid hydrocarbons is a lot easier. If you have a good way to produce lots of hydrogen, you can 1) use it to synthesize hydrocarbons, which our existing infrastructure can handle, or 2) compress it to technologically challenging pressures or cryogenic temperatures, and still have lower energy density. You don't need pure hydrogen to run a fuel cell - a variety of fuel cells you can buy today for powering a home or datacenter run on natural gas.
The vulnerability was disclosed to Google, who has developed a patch, which Google released last week. So, it makes for a funny story, and a teachable moment, but does not necessarily mean OMG-We'z-Been-Hax0red!
As a step in the gradualist progression will be the phase-out of long-haul truckers. Instead, you'll have self-driving trucks that cover 95% of the route (the freeway miles) all by themselves (driving 24/7, as fuel permits), pull into a truck stop just off a prescribed exit, and have a conventional trucker drive it the rest of the way in. I could easily see Wal-Mart, for instance, going this way. The implications for the teamsters could be dire. Would those final-miles drivers be union, or would they be considered scabs? Will we see modern-day luddites attacking or otherwise sabotaging the autonomous trucks? Will this even be an issue in thirty years?
Generally speaking, automation makes us stupid. Oh, sure, it helps free us from drudgery, and won't get bored like up, but presents new failure modes that aren't always obvious during the design and testing phase.
Over the summer, 99% Invisible and NPR's Planet Money put out several podcasts ([1], [2], [3]) on the automation paradox, and the Google car is front and center. So is Air France Flight 447, which shows what happens when automation fails and humans can't properly respond.
I know that the Slashdot crowd (including myself) is largely peopled by native English speakers. I would even hazard that, being mostly Americans, the Slashdot crowd is majority monolingual (I have learned four others, but wouldn't consider myself fluent).
However, being haughtily, disdainfully monolinguial is no excuse for messing up the name of the news organization you are linking to:
It is "Die Welt", not "Der Welt." For heaven's sake, when you click on the link, the correct name is right there on the top of the page in 48-pt font. How do you screw that up?
In German, "der" and "die" are both articles that translate to the English "the," but they have different genders and should not be conflated. ("der" and "die" have more expanded meanings and uses than just "the", but we'll skip that for now.) It would be similar to an American referring to Donald Trump, Barack Obama, Chuck Norris, or Hulk Hogan as "she".
Of course, when MRO finally kicks the bucket, the U.S. program will be down to just MAVEN for communications. So we should, as you say, have another orbiter ready to take over for continuity's sake.
We in the tech industry may be taking it for granted that, by and large, we can hopscotch from job to job however it suits us. In the broader U.S. economy, with official unemployment still above 5%, underemployment around 11%, certain communities (such as poor, minority urban neighborhoods) well above that, and wages more or less flat or declining for the past decade, I would argue we should count our blessings. That also does not consider the situation in, say, most of the rest of the world, where the statistics paint a worse picture.
In any event, the fluctuations in the unemployment rate and layoff figures month-to-month are pretty meaningless. You still like to have the granularity of month-to-month datapoints, but the broader trends are revealed only in longer timescales.
The biggest hurdle is power, and the biggest driver of that isn't the actual computation (i.e., the energy to perform some number of FLOPS), but rather moving that data around (between cores, to/from RAM, across a PCB, and among servers). Other hurdles include how to manage so many cores, ensure they are working (nearly) concurrently, how to handle hardware failures (which will be frequent given the amount of hardware), and writing software that can even make use of such technology in anything approaching optimal fashion.
Not to say its impossible, merely hard given the present state of things and projecting a bit into the future. But as we know, "it is difficult to make predictions, especially about the future." [source?]
The purpose of the investigation was really the atomic-level computer simulation. Specifically, they were investigating whether they could properly simulate the entropy levels of an alloy in the solid and liquid phases, and the heat of fusion required to melt the substance, then extrapolate the melting point from that data. Ultimately, finding a material with a record-high melting point was the challenge used to develop the computation, not an end to itself.
That said, now that they've identified the alloy, the article mentions they are will be collaborating with another institution to synthesize and characterize it, hopefully verifying their calculations and predictions.
Because scaling supersonic aerodynamics up to a spacecraft with twice the size is nontrivial
I'll grant you it is a nontrivial problem, and being able to make it work on a larger vehicle is a slick piece of engineering. On the other hand, the video presents nothing new about those aerodynamics, nor any of the challenges they needed to solve to maintain the concept in SpaceShipTwo. Instead, to use a car analogy, the video goes something like "motorcycles have two wheels, cars have four. Ours product is cool because it has three, something we first developed over a decade ago. The latest version is cooler because it also has three." When you come to that last sentence I hope you will conclude, as I did, that the creation of this video was not at all worth posting on Slashdot.
The feathering mechanism is very clever and effective, and I'm sure that Richard Branson and Virgin Galactic love getting free advertising on Slashdot. But this concept - the mechanism, the shuttlecock behavior, the passive stabilization - was successfully demonstrated when SpaceShipOne won the X-Prize... in 2004.
So please explain, Oh submitter and editors, why are you cluttering up our lives with old news?
It's a developing story. By linking to a Google News search, readers will be able to see (what google's algorithms think are) the most important and relevant news articles related to the topic.
Bonus: if it turns out to all be a hoax, the linked-to Google search will, months or years from now, reflect that.
The linked-to article from the CDC accounts for that. In Figure 3, you'll see the heavily skewed distribution of sugar-drink consumption. About 50% of the population (myself included), consumes zero on any given day, but it goes waaaaay up from there. The 178/103 cal value I used is the average, reported by the authors, across the entire population.
I would argue, however, that this does not change my math, since I'm talking averages. If half of the population isn't drinking any, the way to cut the average consumption in half is for those that are doing the drinking to have a commensurate decrease in their consumption. The ones most affected by drinking would also be most affected by cutting back. (As you have said.) While the half that isn't consuming these drinks would see no weight loss because of others' cutting back (although there's evidence to suggest that your own weight is influenced by the weight of your friends), the ones that are drinking would see more substantial weight loss (and boy do they need it).
Again, on average, the math works out in the way that I have described
which would be a poor investment, because then pepsi would just completely replace coca-cola.. And if you bought them out then some other third party would rise.
Which is why I added "It's total fantasy." I was not making a policy prescription - I was making a scale comparison.
"Overall, males consume an average of 178 kcal from sugar drinks on any
given day, while females consume 103 kcal."
(Nutritional calories (the kind listed on food labels) are equivalent to kilocalories (of the thermodynamic type). I'll use the more coloquial "cal" for the nutritional measure rather than the thermodynamic measure.)
For the purposes of estimating, let's call is 140 (nutrional) cal/person/day.
From a weight loss standpoint, you generally need a caloric deficit of 2500 cal to burn off one pound of fat (approx 500 g). If the consumption of sugar drinks (their definition includes sports drinks, sweetened juices, Kool-Aid, etc.) were cut in half, that would be 70 fewer calories per day per person, or about 25000 cal/year. That represents a weight loss of about 10 pounds per person in the first year.
As for the other aspect of it, soda consumption today versus the 1960s, here at least is one datapoint (Fig. 1): in the 1967, soda production was about 200 12-oz can equivalents per person per year; in 2004, it was about 400.
I stand by my earlier point: if soda consumption today were more like the 1960s, a lot of people would lose a lot of weight, and about as much as I estimated. So, yes, unlike many Slashdotters, I am not merely speaking hyperbolically out of my ass because I want the world to be that way.
Assuming a five year note, average household size of four, and the costs paid entirely by the locals, that should about double the $65/month that is the nominal cost of the system. They'll get that back with taxes eventually, but it's not clear whether the taxes will be on the locals or Statewide. Assuming a five year note, average household size of four, and the costs paid entirely by the locals, that should about double the $65/month that is the nominal cost of the system.
And in the meantime, they'll get an awful lot of value out of it. Plus, the useful life of the fiber is measured in decades, during which it will continue to provide value. Even at a cost of $1900/person, it's a valuable investment.
Heck, I borrowed orders of magnitude more per person for the house I live in! I still considered that a worthwhile expenditure, even though I'll be spending a lot more than five years paying that off.
So in your world view , Sodas are the great satan? It's not uncommon to have the belief.
Sodas are not exactly the great Satan - it is difficult to ascribe morality or cunning evil to a beverage - but they are the single most easily identified and avoidable cause of the problem.
If soda consumption returned to 1960s levels (i.e., 8-12 oz per serving (250-350 mL)), the collective weight of the U.S. population would immediately begin to drop. As a conservative estimate, the weight loss would be 1.5-3.0 million metric tons (5-10 kg per capita, but with a very uneven distribution). I would also hazard that a few million people in the U.S. would avoid Type II diabetes and all the morbidity that comes with that, ultimately saving some hundreds of billions in unnecessary medical costs. In that sense, soda contributes heavily to shortening peoples lives and throttling our economy. Killing us and robbing us; maybe soda really is evil?
Come to think of it... the market capitalization of Coca-Cola is about $175 billion. For that price, the U.S. government should buy them out and shut them down - an investment that would easily pay for itself via reduced Medicare/Medicaid costs over the next generation. It's total fantasy - neither markets nor politics play that way - but that is the scope of the problem and solution.
I expect someone may have worked out the numbers, but for a Mars relay you have more-or-less no attitude control and need a fair bit of power for at least several hours
The article mentions that the MarCO sats will have cold-gas thrusters for course correction and attitude adjustment. There are also a set of three reaction wheels for fine attitude adjustment. I expect the attitude adjustment is for optimal solar panel alignment during the cruise, then for radio alignment during the InSight landing.
(On the other hand, the article says that the MarCO satellites will communicate via X-Band radio to the 70-m receivers in the deep space network. From the picture I don't see anything like a convention "dish" high-gain antenna, so perhaps the radio alignment needs are not terribly stringent)
Why wish for a good wine from Orkney when you can drown your sorrows in some of the best scotch in the world? Each location has its agronomic strengths.
Much as I would like to, I don't live in a climate that can support avocado trees. On the other hand, I don't think there are many sugar maples in Mexico and California, but we have them on every hillside 'round here.
Slashdot Mirror
Another reason: assuming there is good clock synchronization between the data feeds of the two sites, you should be able to use their separation to determine from where in the galaxy the wave came from. (With two sites, you can only narrow down the location so far. Three sites should provide a good fix; N sites would be that much better.)
posting to undo a mistaken moderation
How well do these systems work when their feedstock of CO2 is less than 0.5% pure (i.e. air)?
There are places where the concentration is much higher. For instance, the smokestacks utility-scale, fossil-fueled electrical generators. For instance, there are a variety of large coal plants out in the Arizona and New Mexico deserts, which also have abundant solar (PV and thermal) resources. It may seem a bit strange to co-locate a liquid fuels synthesis plant, hopefully run on variable renewable energy, next to a base-load coal-fired plant, but they each have their uses in the vast landscape of energy supply and demand.
It is a cool dream, but handling liquid hydrocarbons is a lot easier. If you have a good way to produce lots of hydrogen, you can 1) use it to synthesize hydrocarbons, which our existing infrastructure can handle, or 2) compress it to technologically challenging pressures or cryogenic temperatures, and still have lower energy density. You don't need pure hydrogen to run a fuel cell - a variety of fuel cells you can buy today for powering a home or datacenter run on natural gas.
The vulnerability was disclosed to Google, who has developed a patch, which Google released last week. So, it makes for a funny story, and a teachable moment, but does not necessarily mean OMG-We'z-Been-Hax0red!
As a step in the gradualist progression will be the phase-out of long-haul truckers. Instead, you'll have self-driving trucks that cover 95% of the route (the freeway miles) all by themselves (driving 24/7, as fuel permits), pull into a truck stop just off a prescribed exit, and have a conventional trucker drive it the rest of the way in. I could easily see Wal-Mart, for instance, going this way. The implications for the teamsters could be dire. Would those final-miles drivers be union, or would they be considered scabs? Will we see modern-day luddites attacking or otherwise sabotaging the autonomous trucks? Will this even be an issue in thirty years?
Generally speaking, automation makes us stupid. Oh, sure, it helps free us from drudgery, and won't get bored like up, but presents new failure modes that aren't always obvious during the design and testing phase.
Over the summer, 99% Invisible and NPR's Planet Money put out several podcasts ([1], [2], [3]) on the automation paradox, and the Google car is front and center. So is Air France Flight 447, which shows what happens when automation fails and humans can't properly respond.
Wait, I thought it was the pit of despair.
[clears throat] Don't even think about trying to escape.
However, being haughtily, disdainfully monolinguial is no excuse for messing up the name of the news organization you are linking to:
It is "Die Welt", not "Der Welt." For heaven's sake, when you click on the link, the correct name is right there on the top of the page in 48-pt font. How do you screw that up?
In German, "der" and "die" are both articles that translate to the English "the," but they have different genders and should not be conflated. ("der" and "die" have more expanded meanings and uses than just "the", but we'll skip that for now.) It would be similar to an American referring to Donald Trump, Barack Obama, Chuck Norris, or Hulk Hogan as "she".
The MAVEN orbiter also serves as a communications relay. As a matter of fact, getting it to Mars to take over communications was deemed so important the launch was allowed to proceed during the last government shutdown.
Of course, when MRO finally kicks the bucket, the U.S. program will be down to just MAVEN for communications. So we should, as you say, have another orbiter ready to take over for continuity's sake.
We in the tech industry may be taking it for granted that, by and large, we can hopscotch from job to job however it suits us. In the broader U.S. economy, with official unemployment still above 5%, underemployment around 11%, certain communities (such as poor, minority urban neighborhoods) well above that, and wages more or less flat or declining for the past decade, I would argue we should count our blessings. That also does not consider the situation in, say, most of the rest of the world, where the statistics paint a worse picture.
In any event, the fluctuations in the unemployment rate and layoff figures month-to-month are pretty meaningless. You still like to have the granularity of month-to-month datapoints, but the broader trends are revealed only in longer timescales.
Kodak tried this some years ago: sell consumer printers that have higher upfront costs but lower consumable cost.
Like a lot of things they tried before ultimately declaring bankruptcy, Kodak failed at this.
IEEE Spectrum had an article last year describing some of the challenges we'll need to overcome in order to achieve exascale computing.
Here's another, somewhat pessimistic piece they posted in 2008 - a digest of a DARPA report that went into significant technical detail.
The biggest hurdle is power, and the biggest driver of that isn't the actual computation (i.e., the energy to perform some number of FLOPS), but rather moving that data around (between cores, to/from RAM, across a PCB, and among servers). Other hurdles include how to manage so many cores, ensure they are working (nearly) concurrently, how to handle hardware failures (which will be frequent given the amount of hardware), and writing software that can even make use of such technology in anything approaching optimal fashion.
Not to say its impossible, merely hard given the present state of things and projecting a bit into the future. But as we know, "it is difficult to make predictions, especially about the future." [source?]
The purpose of the investigation was really the atomic-level computer simulation. Specifically, they were investigating whether they could properly simulate the entropy levels of an alloy in the solid and liquid phases, and the heat of fusion required to melt the substance, then extrapolate the melting point from that data. Ultimately, finding a material with a record-high melting point was the challenge used to develop the computation, not an end to itself.
That said, now that they've identified the alloy, the article mentions they are will be collaborating with another institution to synthesize and characterize it, hopefully verifying their calculations and predictions.
I'll grant you it is a nontrivial problem, and being able to make it work on a larger vehicle is a slick piece of engineering. On the other hand, the video presents nothing new about those aerodynamics, nor any of the challenges they needed to solve to maintain the concept in SpaceShipTwo. Instead, to use a car analogy, the video goes something like "motorcycles have two wheels, cars have four. Ours product is cool because it has three, something we first developed over a decade ago. The latest version is cooler because it also has three." When you come to that last sentence I hope you will conclude, as I did, that the creation of this video was not at all worth posting on Slashdot.
The feathering mechanism is very clever and effective, and I'm sure that Richard Branson and Virgin Galactic love getting free advertising on Slashdot. But this concept - the mechanism, the shuttlecock behavior, the passive stabilization - was successfully demonstrated when SpaceShipOne won the X-Prize ... in 2004.
So please explain, Oh submitter and editors, why are you cluttering up our lives with old news?
What would a crummy lossless recording sound like? Are there lossless codecs that introduce new artifacts?
It's a developing story. By linking to a Google News search, readers will be able to see (what google's algorithms think are) the most important and relevant news articles related to the topic.
Bonus: if it turns out to all be a hoax, the linked-to Google search will, months or years from now, reflect that.
The linked-to article from the CDC accounts for that. In Figure 3, you'll see the heavily skewed distribution of sugar-drink consumption. About 50% of the population (myself included), consumes zero on any given day, but it goes waaaaay up from there. The 178/103 cal value I used is the average, reported by the authors, across the entire population.
I would argue, however, that this does not change my math, since I'm talking averages. If half of the population isn't drinking any, the way to cut the average consumption in half is for those that are doing the drinking to have a commensurate decrease in their consumption. The ones most affected by drinking would also be most affected by cutting back. (As you have said.) While the half that isn't consuming these drinks would see no weight loss because of others' cutting back (although there's evidence to suggest that your own weight is influenced by the weight of your friends), the ones that are drinking would see more substantial weight loss (and boy do they need it).
Again, on average, the math works out in the way that I have described
Which is why I added "It's total fantasy." I was not making a policy prescription - I was making a scale comparison.
"Overall, males consume an average of 178 kcal from sugar drinks on any given day, while females consume 103 kcal."
(Nutritional calories (the kind listed on food labels) are equivalent to kilocalories (of the thermodynamic type). I'll use the more coloquial "cal" for the nutritional measure rather than the thermodynamic measure.)
For the purposes of estimating, let's call is 140 (nutrional) cal/person/day.
From a weight loss standpoint, you generally need a caloric deficit of 2500 cal to burn off one pound of fat (approx 500 g). If the consumption of sugar drinks (their definition includes sports drinks, sweetened juices, Kool-Aid, etc.) were cut in half, that would be 70 fewer calories per day per person, or about 25000 cal/year. That represents a weight loss of about 10 pounds per person in the first year.
As for the other aspect of it, soda consumption today versus the 1960s, here at least is one datapoint (Fig. 1): in the 1967, soda production was about 200 12-oz can equivalents per person per year; in 2004, it was about 400.
I stand by my earlier point: if soda consumption today were more like the 1960s, a lot of people would lose a lot of weight, and about as much as I estimated. So, yes, unlike many Slashdotters, I am not merely speaking hyperbolically out of my ass because I want the world to be that way.
And in the meantime, they'll get an awful lot of value out of it. Plus, the useful life of the fiber is measured in decades, during which it will continue to provide value. Even at a cost of $1900/person, it's a valuable investment.
Heck, I borrowed orders of magnitude more per person for the house I live in! I still considered that a worthwhile expenditure, even though I'll be spending a lot more than five years paying that off.
Sodas are not exactly the great Satan - it is difficult to ascribe morality or cunning evil to a beverage - but they are the single most easily identified and avoidable cause of the problem.
If soda consumption returned to 1960s levels (i.e., 8-12 oz per serving (250-350 mL)), the collective weight of the U.S. population would immediately begin to drop. As a conservative estimate, the weight loss would be 1.5-3.0 million metric tons (5-10 kg per capita, but with a very uneven distribution). I would also hazard that a few million people in the U.S. would avoid Type II diabetes and all the morbidity that comes with that, ultimately saving some hundreds of billions in unnecessary medical costs. In that sense, soda contributes heavily to shortening peoples lives and throttling our economy. Killing us and robbing us; maybe soda really is evil?
Come to think of it... the market capitalization of Coca-Cola is about $175 billion. For that price, the U.S. government should buy them out and shut them down - an investment that would easily pay for itself via reduced Medicare/Medicaid costs over the next generation. It's total fantasy - neither markets nor politics play that way - but that is the scope of the problem and solution.
The article mentions that the MarCO sats will have cold-gas thrusters for course correction and attitude adjustment. There are also a set of three reaction wheels for fine attitude adjustment. I expect the attitude adjustment is for optimal solar panel alignment during the cruise, then for radio alignment during the InSight landing.
(On the other hand, the article says that the MarCO satellites will communicate via X-Band radio to the 70-m receivers in the deep space network. From the picture I don't see anything like a convention "dish" high-gain antenna, so perhaps the radio alignment needs are not terribly stringent)
Why wish for a good wine from Orkney when you can drown your sorrows in some of the best scotch in the world? Each location has its agronomic strengths.
Much as I would like to, I don't live in a climate that can support avocado trees. On the other hand, I don't think there are many sugar maples in Mexico and California, but we have them on every hillside 'round here.