The probe was sterilized, if I recall correctly. So it shouldn't be an issue.
Keep in mind that in the long history of the solar system it's likely that material blasted off the earth by an impact event or events has made its way to the surface of Titan. So Titan may have already been contaminated with life from earth.
Certainly, I don't disagree that highly elliptical orbits which literally fry a given world for months at a time before plunging it into the freezing depths of a given solar system for years would represent a potentially insurmountable challenge, at least to complex surface life.
I do wonder though if we might end up finding bizarre worlds in what might be otherwise be considered inhospitably elliptical orbits, where the "fry" phase turns out to be just enough energy to, for example, keep a global ocean from ever freezing over. The surface might be a pretty awful place on such a world, but the oceans could end up perfectly hospitable, since presumably zones of stable temperature would simply migrate toward and away from the ocean surface over the course of a year.
True, but highly elliptical orbits pose not only the problem of harsh conditions, but of rapidly changing, oscillating conditions.
Yes, but there are many other factors to consider. For example, with a highly elliptical orbit, a planet would spend far more time in the outermost portion of its orbit than it would spend close to its sun. So while the orbital summer experienced might be severe, it would also be brief. Here on earth all sorts of lifeforms exhibit the ability to survive brief climatic extremes, and even lengthy extremes in many cases (for example, animals in the arctic and in Antarctica). If anything, such environments seem to encourage evolution. So it isn't at all clear that extreme planetwide seasons would be bad for life in general. They could in fact prove to be a good thing, at least to some degree.
Beyond that, there are all sorts of factors which could mitigate the impact such orbital extremes might have. For example, an atmosphere substantially thicker than the earth's would serve to better-insulate a planet and to distribute heat to the far side of the planet. Such a world's climate could end up far less extreme than that of the earth, even though its orbit is substantially more elliptical.
People also seem to neglect the possibility of habitable moons. In our own solar system there are only 4 terrestrial planets, but dozens of moons. We're finding many systems where enormous gas giant planets orbit within the habitable zones of their suns. Often these worlds are many times more massive than Jupiter, implying they could posses rocky moons as massive as Mars, the Earth or even bigger. Many of these moons would have short stable days and because of tidal heating are virtually guaranteed to have molten cores and therefore their own magnetic fields (even fairly low-mass moons). They'd also benefit from reflected and even radiant heat coming from the massive planet they orbit, which would help to substantially expand the habitable zone of these systems and smooth climatic extremes on worlds in more elliptical orbits.
There are certainly other variables we haven't even considered yet, because we have so little data to go on at this time. We can already perform some informed guesses based on what little we know - there's nothing wrong with that - but clearly we still have a lot to learn before we can assess the frequency of potentially habitable worlds in the cosmos. It is however very exciting to be living in a time when we're about to acquire the data to make valid estimates possible.
Less global tidal energy means less vertical mixing.
Are you sure about that? I thought most of the mixing was due to ocean currents, not tides. The tides only impact the uppermost portion of the water column. The rise and fall of ocean currents is what does most of the mixing, and last I checked those have more to do with temperature and salinity differences than with the tides.
There is so much potential energy in moving water though that I find it unlikely we'd tap or need to tap enough of it (or have the ability to tap enough of it) to make a big difference in ocean mixing. And if doing so displaces CO2-belching sources of power, so much the better. Greenhouse warming is likely to have a far greater impact on ocean currents longterm.
The original iPod's design was clearly heavily influenced by the design of Braun products - especially radios - from the 1950's and '60s. Braun's historic designs are widely regarded as some of the best examples of industrial design from the 20th century. Many Braun designs are on display at the Museum of Modern Art in Manhattan. Saying that something looks "like a Braun product" - if you're comparing it to one of Braun's traditional designs - is an enormous compliment.
That having been said, this new iPhone - if it indeed is an iPhone - reminds me more of Sony's designs from the early 1980's. Which isn't a bad thing - that's the period during which Sony reached its design peak, and influenced the rest of the consumer electronics industry.
I wonder if the seams are functional, though. If the case is all metal, perhaps the seams are there for the antenna to use.
Soyuz uses an entirely different type of fuel than the Shuttles do - a highly refined form of kerosene, as opposed to the expensive to handle liquid hydrogen used by the Shuttles (which also utilize solid rocket boosters - a questionable choice for a manned launch vehicle, and one which already resulted in a spectacular catastrophe).
Soyuz launches payloads into orbit for a cost of around $2,000 a pound. The Shuttles are up to about $4,000 a pound now, depending on how you handle the accounting for the overall program cost, and aren't anywhere near as reliable, in spite of their incredible cost.
Soyuz is such an inexpensive and reliable booster it's become - by far - the most used launcher in the world. It's proven so popular and cost-effective that the ESA has made a deal with the Russians to bring Soyuz to their Kourou launch site, currently used by Europe's Ariane boosters, with a launch scheduled for later this year.
You can Google all of this in under 10 minutes. There's really no excuse for being as belligerently, stunningly ignorant as you are.
Soyuz - which is the current Soviet manned space booster - hasn't had a fatal accident now in decades. It's old but very reliable. My guess is the big US aerospace firms can't really compete with it, at least not without sinking many billions into development costs and potentially having their own string of catastrophic failures to learn from (the way the Soviets did). They're probably also worried about demand for manned boosters going forward, and possible competition from the Russians, Europeans and - eventually - Chinese. Even if the US aerospace firms were successful in developing a manned booster, it might be difficult for them to ever recoup their development costs due to competition alone. They may feel there are better ways to spend their money, probably on defense-related programs where the margins are much higher and the competition less intense.
I know this is very anti-postmodern, but just because you don't see or don't know about something, doesn't mean it's not real.
It's not the physical gradient, it's displacing that much water over a short period of time. When an earthquake generates a tsunami it's not generally uplifting the local seabed by meters, but it's uplifting (or dropping) it by inches over a wide area. The impact of a large glacier sliding off a continent into the water quickly would be similar.
Add those kind of waves onto 2 meters of sea level rise and you'd have massive flooding on a global scale of most coastal communities. Even without the tsunami, most of today's coastal communities would become far more vulnerable to catastrophic flooding during storms. Which is probably why Lovelock suggests beefing up our defenses now, before it's too late.
It goes beyond that. Even if you assume all the CO2 we're pumping into the atmosphere has zero impact on climate, the climate is gonna change, and potentially within the lifetimes of most of the people reading this post. There's a great deal of evidence that big glaciers in Antarctica are melting faster than they're being replenished, and that some of them could catastrophically slip into the sea within the next few hundred years. We've been lucky to avoid any globe-spanning natural disasters like that throughout the past couple thousand years, but our luck won't hold forever. A lot of the defensive measures Lovelock advocates for combating climate change - like improving flood barriers on the Thames for the city of London, or perfecting methods for synthesizing food - will likely pay off even if we get lucky and all that CO2 doesn't itself contribute to a great melt.
For example, what happens if the Yellowstone Supervolcano blows? You could have crop failures for years, not just in the US but elsewhere around the globe. That might do more than suspend democracy - it could suspend civilization. An ability to synthesize food could come in very handy in such a situation (unless you want to unwillingly become Soylent Green for some starving mob).
It seems to me that what Lovelock is arguing is that the science tells us there are these threats, these global threats to the security of our civilization, and that we should be planning for them accordingly now while we can so that we don't have to cope with them entirely unprepared if/when hey do roll around.
He's also making assumptions, like "when a major war approaches".... who says major wars are needed, ever?
Where does Lovelock assert that major wars are needed, ever?
That's right - he doesn't.
He merely observes that when major wars approach, democracies have tended to suspend at least some of their standard peacetime practices. I fail to see how this observation could be remotely controversial, as there are innumerable examples to be drawn from the histories of the major western democracies.
he's not calling for an end to democracy. He's simply telling everybody they'll be sorry if they don't listen to him.
It's a little more complicated than that. Reading the entire interview, I think it would be more to the point to say that Lovelock is a strong advocate of having contingency plans in place at least to cope with climate change, especially involving coastal defenses against flooding. He also brings up the subject of having the capacity to manufacture synthetic food, probably to deal with crop failures brought on by sudden (or even prolonged) climate-related catastrophes.
Is that what he's saying? Or is he saying that when the climate sh*t hits the fan, governments may start to put democracy "on hold" while they attempt to deal with it? If you actually read what he says in the interview, his focus is more on what we can do in terms of disaster preparedness than on reducing carbon emissions.
If, for example, the Pine Island Glacier in Antarctica catastrophically slips into the ocean, creating tsunamis and raising global sea levels by about 2 meters overnight, who knows what governments will end up doing in response. I suspect a lot of it would involve the at least partial suspension of democracy as we've known it, while governments scramble to deal with what amounts to a global natural disaster, impacting many if not most coastal cities, where a majority of the global population lives or works and where at least half of the gross planetary product is generated.
Except this isn't an example of either the efficiency or effectiveness of "centralized control". Centralized control would be if the government operated its own testing labs and certified itself whether products are Energy Star compliant or not. Instead, they're relying on the private sector producers of the products themselves to supply their own data, with entirely predictable results.
If something can interact with things in our universe then it is in our universe
That's how you're defining the universe. That isn't the only definition of the universe, or rather, of our universe. You could have matter in two or more separate universes which can never physically interact apart from a force or forces which can bleed between universes. So maybe (some) gravity leeches out, but not EM, and matter from one universe can never physically enter the other.
String theory predicts multiple universes. And there's growing observational evidence to back up the assertion that other universes could be acting upon our own. Google "dark flow", for example. Check out the New Scientist article from Jan 23, 2009 - here's a quote from it:
Many cosmologists are happy to relegate those other universes to that dusty corner of theory where unobservable by-products are stored. Mersini-Houghton is not one of them. She argues that the dark flow is caused by other universes exerting a gravitational pull on galaxy clusters in our universe. She and her colleagues calculated how other universes, scattered at random around our bubble, would alter the gravity within it (www.arxiv.org/abs/0810.5388). "When we estimated how much force is exerted on the clusters in our universe, I was surprised that the number matched amazingly well with what Kashlinsky has observed," she says. "I firmly believe that this is the effect of something outside of our universe."
Other universes, if they exist, cannot interact with ours.
That's an assertion, but we don't know this for a fact. "Dark matter" may in fact be evidence that other universes do interact with our own. So maybe gravity isn't (entirely) bounded to the universe it originates in.
Or maybe what we consider the "visible" universe is just part of a much, much larger structure.
90% of the matter in the Universe is in a form that emits no light, but affects other matter through gravity.
Do we know for certain that the "dark matter" itself - whatever it proves to be - is actually in our universe? Is it possible that "dark matter" is just regular matter in some other universe(s) whose gravity is bleeding into our own?
Others have speculated that a megatsunami - possibly caused by the collapse of a volcanic island during an eruption or even a meteorite / comet strike - could have been the origin of the flood myth. It's interesting to note that many civilizations around that part of the world apparently shared the myth of a great flood.
I suppose it's also possible there were several different flood events that got melded into one great flood myth.
That's what the RIAA EQ curve is for. The bass is attenuated at recording and enhanced at playback.
The RIAA curve was an attempt to mitigate the problem - it does not solve it. As I already pointed out, there's really only one way around it - have your mastering engineer screw with your material until it fits within vinyl's limitations. You can reduce the amount of tweaking that needs to be done by placing only one or two songs on a 12" 45RPM EP or single, half or quarter-speed mastered, but even there vinyl doesn't have the unlimited bass capacity of CD. And I don't think most people want to buy 4 or 5 vinyl discs just to get the same material that would fit totally unaltered on a single CD!
LPs contain frequencies from subsonic to supersonic.
Yes, they can, but when it comes to subsonics, not anything at volume - certainly not on an LP. The grooves can't be wide enough if you're trying to fit 20 minutes or more onto a side. And a good portion of that subsonic and ultrasonic material is noise and distortion not present in digital media (or even other analog media, like cassette and VHS Hi-Fi).
In short, son, you have no idea what you're talking about. You obviously never even heard of the RIAA equalization curve.
Wait a minute - you just claimed that the RIAA equalization curve allows LP's - not just vinyl, but LP's - to record loud low frequency bass, and then you have the audacity to tell me that I don't know what I'm talking about? Why do you think vinyl required such careful mastering to begin with if the freakin' equalization curve automatically took care of everything?
Dolt.
The recordings had more bass because the original performance had more bass.
A lot of those performances with that kind of bass couldn't have been distributed, at least not as LPs. Both the boom car hip-hop craze and house music really took off here in the States once music distribution switched to CD and suddenly everyone could have club bass in their home or car without being forced to buy nothing but 12" singles and without having to shell out a fortune on turntables and preamps.
Rumle is virtually nonexistant on even a moderately good table.
A nice audiophile table like the Music Hall MMF 2.1LE - which goes for around $500 - sports rumble of -70dB. Note this doesn't include the rumble recorded on the record as it was mastered, or other low-frequency noise caused by the needle scraping thru the groove and especially into the walls of the leading edge of the groove. If you consider -70dB "virtually nonexistant", I suppose you also don't care about all those hypersonic signals that are supposedly so important, many of which are down at -70dB and below.
I'd just like to add here that you can get rumble of -infinity from a $50 CD player.
Oh, and I hope you weren't planning on playing your music very loud. You do know that the turntable, platter, pickup and the record itself all act like a giant microphone, right? They absorb and transmit whatever bass frequencies they're exposed to right back to the needle, in the worst instances resulting in a nasty blast of feedback. This is yet another ridiculous vinyl limitation that CD doesn't suffer from.
I'm not even going to bother reading the rest of your ill-informed comment, the ignorance is painful to my brain.
Sorry, dude. I apparently poured too much accurate information into your brain for it to handle. I guess you overloaded and skipped a groove, kinda like vinyl. My bad! Maybe I shoulda mixed everything to mono first so you could take it!
I haven't even brought up all the issues caused by the RIAA equalization curve. Suffice to say, when CD's rolled out the vinyl lovers were all in a tizzy over the brick wall filters that the CD format utilized above 20kHz to avoid Nyquist issues with 44.1kHz digital recording. Oh, it was awful, they wailed. The sound is so colored by those terrible brick wall filters, which supposedly caused phase issues and colored the sound and resulted in cats sleeping with dogs. All because that awful brick wall filter was sitting up there at the high end of the audio spectrum.
Well, guess what, kids - the RIAA equalization curve is about as dramatic, runs across the whole damn audible spectrum instead of being confined to the far upper range of human hearing, and creates a host of issues of its own. For starters, since the amount of equalization varies with frequency, there are all sorts of nasty phase and distortion issues that crop up. Also, because no two analog circuits are quite the same, there's gonna be variation between the encoding done on the master and the decoding done by your preamp. There goes fidelity right out the window!
I mean, it's a neat hack to overcome both vinyl's total inability to handle loud bass (which is deemphasized by a maximum of 20dB on recording) and to drown out high-frequency noise (high frequencies in the material are emphasized on recording by about 20dB), but it also does nasty things like enhance rumble and make good cutting heads more costly to produce (to handle such a hot high-end signal). It ain't exactly high-fidelity, but it beats grandpa's 78's on his Victrola.
No, I just pulled up the track in Goldwave to have a look. There's a ton of very low frequency signal, the kind of signal that would be difficult or impossible to record on vinyl. That kind of loud deep bass went from being an anomaly to being commonplace in the span of a couple of years once CDs were widely adopted. You might be able to deliver something approximate to it as a 12" vinyl single with very careful mastering, but you certainly couldn't just record that exact kind of material on a vinyl LP. You'd wreck the equipment! Whereas with CD, you could deliver it to millions on a 74 minute recording, no babysitting, no tampering required.
bass reproduction is not so constrained by the playback media as the playback equipment.
Well gee, the same thing is even truer for ultrasonics, yet that hasn't stopped the vinyl brigade from hyping vinyl's supposed superiority above 20kHz for the better part of two decades. At least most people can hear and feel bass down to 20Hz. Virtually nobody can hear whatever ultrasonics vinyl manages to record.
I can hear a discernable difference to the harmonics of many instruments if I apply a 24db/octave low pass filter at 16k and I've played in rock bands for 20 years.
Yeah, but CD goes up to 20kHz, and does so without all of the noise, phase issues, and equalization / re-equalization issues of vinyl (did we discuss the distortion caused by the application of the RIAA equalization curve yet?). If you apply a filter at 20kHz do you notice much of a difference?
Thus, the surface noise and distortions inherent with vinyl conspire to make something like the Who's My Generation sound fucking awesome on 7" vinyl. By comparison, that same track sounds relatively dull and lifeless on CD.
Is it the noise and distortion? Or did somebody just do a shitty job mastering the CD? I have multiple copies of some records on CD which sound radically different, depending on how they were mastered (and what they were mastered from, for that matter).
Wrong. The RIAA curve doesn't prevent loud low bass - especially stereo bass pans - from flipping the needle right out of the groove. That's because vinyl can't handle loud low bass - it's physically incapable of it. What do you expect from a format that was created a hundred years ago for anything BUT high fidelity? Mastering engineers have to ride the gain, mix to mono, vary the track pitch and pull all sorts of other tricks just to cut any record at a decent level - it's still very much an art and not entirely a science.
Can you get loud low bass onto vinyl? Sort of. If you work at it hard enough. You have to mix it to mono, attenuate the deepest loud frequencies, and then cut a 45RPM 12" on heavy virgin half speed mastered vinyl. Note that none of this is exactly high fidelity - you're jacking with the original recording in order to squeeze it onto vinyl. And even then, assuming you can cut the thing without destroying your equipment, you run the risk of the record being unplayable on some turntables. So, mastering engineers tend to be pretty conservative, which just further butchers the material.
CD doesn't have any of these ridiculous limitations. You can record as much loud low bass - or screeching treble - as you want, until it clips just like any other signal would. You'd probably blow up a lot of folks' speakers that way if you took it to the extreme, but the disc itself would still play just fine.
I won't even go into all the crap mastering engineers have to do in order to keep high frequencies from frying a lathe's cutter. Let's just say there's nothing remotely high-fidelity about vinyl and leave it at that.
String, reed and brass instruments all have harmonics and overtones extending well beyond 20k.
Faint overtones, which the microphone may or may not have been able to pickup at even lower levels, due to the rolloff in response in most audio equipment above about 20kHz. And even if the mics did manage to pick up an audible amount of those overtones, did the console filter them out? Did the tape deck record it? Did the vinyl mastering engineer cut them off, in order to reserve vinyl's limited capacity for high-frequency signals for stuff that's more audible? Can your own pickup and amp reproduce them? Your speakers? Most speakers rolloff steeply over 20kHz - combine that with the rolloff from most microphones and you've suppressed high frequency signals so much they're completely inaudible. Assuming they were ever audible over all of vinyl's high-frequency noise to begin with.
The 9db rule is that sounds of the same and nearby frequencies are masked, not that energy in the 15k region masks 20k.
That's not entirely true. The acuity of our hearing decreases as you approach the upper limits of its range. We even have a very hard time differentiating between noise and signal, especially once you get up around 20kHz or so. Unless the material is absolutely saturated with signal up there, you can swap an equal amount of one for the other - especially up above 18kHz or so - and it's awfully hard for listeners to tell the two apart when there's substantial signal present at other parts of the spectrum. (Shaped noise obviously, not constant noise which would be apparently different - but which can also add an air of space to a recording).
Try that down at 1,000Hz!
So all this arguing over the near-ultrasonic performance of various audio formats is like arguing over how many angels can dance on the head of a pin. Half the audience is stone deaf over 18kHz anyhow, and most of the rest can't tell the difference between 18kHz noise and 18kHz signal. Clearly, whatever stuff is or isn't being recorded and reproduced up there isn't terribly important compared to the rest of the audio spectrum.
u87's roll off from 15-16k, to about -9db at 20k. There's actually a slight peak around or slightly above 20k because it's the first harmonic of the resonant frequency of the diaphragm (which is around 10kHz).
The manufacturer claims 20kHz as the limit, last time I checked. Any harmonics being generated may not actually reflect program material the microphone was intended to record, but are instead harmonic distortion being generated by the diaphragm. One more reason to discard frequencies outside the range of human hearing - the recording and playback equipment we use is capable of throwing more signal than noise at those frequencies, so why rob amplifier power and tax your speakers to playback a bunch of noise and distortion? Better to reserve all that for linear performance in the audible range.
Ignoring that cymbals are rarely mic'd directly and that I've never seen SM57's used for drum overheads because the mechanical action of the microphones coil would damp high frequencies
Oh really? Because a quick Google of SM57 drum overhead reveals about 115,000 hits. Larry Mullen is apparently using them for overheads on U2 records, from what I could find on Google. The Red Hot Chili Peppers apparently record just about everything with SM57's, even vocals. Maybe they want the high frequencies dampened a bit. Imagine that! (Probably can't hear 'em anymore, anyhow.)
The frequency response of mics does not "top out", it slopes off.
Yes, and often it slopes off dramatically, which is what I'm referring to when I say, "top out" - the point at which it stops being fairly flat and goes into obvious, often dramatic decline. The same thing happens with speakers. Between the rolloff in the mic's response and the rolloff in your own speakers' response, it's entirely likely there's no audible, intentional signal presen
A lot of the articles I read on the subject in the past were either in magazines, or are gone from the web now. Mix magazine has an article which touches on some of vinyl's limitations:
Apart from that, check Wikipedia for articles regarding stuff like the RIAA equalization curve, or just Google the specifications for things like microphones and analog tape decks. You'll quickly discover that a lot of the "high frequency" information some audiophiles claim to be hearing can't possibly have been intentionally recorded. In other words, it's noise.
The following comes from an old April issue of Audio Magazine. It cleverly points out some of vinyl's many failings:
NEW PRODUCT ANNOUNCEMENT
The LIRPA-1 CD Enhancer/LP Record Simulator:
A revolutionary new device for all those who believe that CD players produce "mid-fi" results, and that analog recordings (LPs) are superior to CDs.
PURPOSE:
This device allows you to tailor the signal produced by the
Compact Disk medium to more closely resemble that of LP records.
It can be placed between the Compact Disk player and your
receiver, in a tape monitor loop or external processing loop, or
between the preamp and power amplifier of your stereo system.
STANDARD FEATURES:
o HARMONIC DISTORTION GENERATOR: Adjustable from 0% to 100% THD
(total harmonic distortion). This allows you to increase the total
harmonic distortion of the Compact Disk from 0.01% to levels found
on typical LPs played with "top-of-the-line" stereo cartridges
(commonly 1% THD +). An additional benefit is found in that this
control also contributes to that ultra-sonic information above
22kHz which was "lost" in the digital process.
o SEPARATION-REDUCTION CONTROL: Permits variable blending of left and
right channels over a range from 90dB separation (found on Compact
Disks) to full blending (monophonic sound). Adjustment of about
30dB separation is recommended to simulate the typical "state-of-
the-art" stereo cartridge.
o DYNAMIC RANGE COMPRESSOR: Now you don't have to worry whether your
power amplifier or your speakers are "Digital-Ready". This knob
allows you to reduce the dynamic range of the Compact Disk from
90dB to as low as 45dB. This is a definite "must" for those who
prefer the TELARC 1812 LP to the TELARC 1812 CD (suggested adjustment
for this recording: 65dB).
o SUB-SONIC DOPPLER DISTORTION GENERATOR: Superimposes sub-sonic
Slashdot Mirror
The probe was sterilized, if I recall correctly. So it shouldn't be an issue.
Keep in mind that in the long history of the solar system it's likely that material blasted off the earth by an impact event or events has made its way to the surface of Titan. So Titan may have already been contaminated with life from earth.
Certainly, I don't disagree that highly elliptical orbits which literally fry a given world for months at a time before plunging it into the freezing depths of a given solar system for years would represent a potentially insurmountable challenge, at least to complex surface life.
I do wonder though if we might end up finding bizarre worlds in what might be otherwise be considered inhospitably elliptical orbits, where the "fry" phase turns out to be just enough energy to, for example, keep a global ocean from ever freezing over. The surface might be a pretty awful place on such a world, but the oceans could end up perfectly hospitable, since presumably zones of stable temperature would simply migrate toward and away from the ocean surface over the course of a year.
Interesting times!
True, but highly elliptical orbits pose not only the problem of harsh conditions, but of rapidly changing, oscillating conditions.
Yes, but there are many other factors to consider. For example, with a highly elliptical orbit, a planet would spend far more time in the outermost portion of its orbit than it would spend close to its sun. So while the orbital summer experienced might be severe, it would also be brief. Here on earth all sorts of lifeforms exhibit the ability to survive brief climatic extremes, and even lengthy extremes in many cases (for example, animals in the arctic and in Antarctica). If anything, such environments seem to encourage evolution. So it isn't at all clear that extreme planetwide seasons would be bad for life in general. They could in fact prove to be a good thing, at least to some degree.
Beyond that, there are all sorts of factors which could mitigate the impact such orbital extremes might have. For example, an atmosphere substantially thicker than the earth's would serve to better-insulate a planet and to distribute heat to the far side of the planet. Such a world's climate could end up far less extreme than that of the earth, even though its orbit is substantially more elliptical.
People also seem to neglect the possibility of habitable moons. In our own solar system there are only 4 terrestrial planets, but dozens of moons. We're finding many systems where enormous gas giant planets orbit within the habitable zones of their suns. Often these worlds are many times more massive than Jupiter, implying they could posses rocky moons as massive as Mars, the Earth or even bigger. Many of these moons would have short stable days and because of tidal heating are virtually guaranteed to have molten cores and therefore their own magnetic fields (even fairly low-mass moons). They'd also benefit from reflected and even radiant heat coming from the massive planet they orbit, which would help to substantially expand the habitable zone of these systems and smooth climatic extremes on worlds in more elliptical orbits.
There are certainly other variables we haven't even considered yet, because we have so little data to go on at this time. We can already perform some informed guesses based on what little we know - there's nothing wrong with that - but clearly we still have a lot to learn before we can assess the frequency of potentially habitable worlds in the cosmos. It is however very exciting to be living in a time when we're about to acquire the data to make valid estimates possible.
Less global tidal energy means less vertical mixing.
Are you sure about that? I thought most of the mixing was due to ocean currents, not tides. The tides only impact the uppermost portion of the water column. The rise and fall of ocean currents is what does most of the mixing, and last I checked those have more to do with temperature and salinity differences than with the tides.
There is so much potential energy in moving water though that I find it unlikely we'd tap or need to tap enough of it (or have the ability to tap enough of it) to make a big difference in ocean mixing. And if doing so displaces CO2-belching sources of power, so much the better. Greenhouse warming is likely to have a far greater impact on ocean currents longterm.
The song's title is Poke Salad Annie:
http://en.wikipedia.org/wiki/Poke_Salad_Annie
Salad. Not "Salat".
You'll think gaping hole after Shatner is through with you.
The original iPod's design was clearly heavily influenced by the design of Braun products - especially radios - from the 1950's and '60s. Braun's historic designs are widely regarded as some of the best examples of industrial design from the 20th century. Many Braun designs are on display at the Museum of Modern Art in Manhattan. Saying that something looks "like a Braun product" - if you're comparing it to one of Braun's traditional designs - is an enormous compliment.
That having been said, this new iPhone - if it indeed is an iPhone - reminds me more of Sony's designs from the early 1980's. Which isn't a bad thing - that's the period during which Sony reached its design peak, and influenced the rest of the consumer electronics industry.
I wonder if the seams are functional, though. If the case is all metal, perhaps the seams are there for the antenna to use.
Soyuz uses an entirely different type of fuel than the Shuttles do - a highly refined form of kerosene, as opposed to the expensive to handle liquid hydrogen used by the Shuttles (which also utilize solid rocket boosters - a questionable choice for a manned launch vehicle, and one which already resulted in a spectacular catastrophe).
Soyuz launches payloads into orbit for a cost of around $2,000 a pound. The Shuttles are up to about $4,000 a pound now, depending on how you handle the accounting for the overall program cost, and aren't anywhere near as reliable, in spite of their incredible cost.
Soyuz is such an inexpensive and reliable booster it's become - by far - the most used launcher in the world. It's proven so popular and cost-effective that the ESA has made a deal with the Russians to bring Soyuz to their Kourou launch site, currently used by Europe's Ariane boosters, with a launch scheduled for later this year.
You can Google all of this in under 10 minutes. There's really no excuse for being as belligerently, stunningly ignorant as you are.
Soyuz - which is the current Soviet manned space booster - hasn't had a fatal accident now in decades. It's old but very reliable. My guess is the big US aerospace firms can't really compete with it, at least not without sinking many billions into development costs and potentially having their own string of catastrophic failures to learn from (the way the Soviets did). They're probably also worried about demand for manned boosters going forward, and possible competition from the Russians, Europeans and - eventually - Chinese. Even if the US aerospace firms were successful in developing a manned booster, it might be difficult for them to ever recoup their development costs due to competition alone. They may feel there are better ways to spend their money, probably on defense-related programs where the margins are much higher and the competition less intense.
I know this is very anti-postmodern, but just because you don't see or don't know about something, doesn't mean it's not real.
It's not the physical gradient, it's displacing that much water over a short period of time. When an earthquake generates a tsunami it's not generally uplifting the local seabed by meters, but it's uplifting (or dropping) it by inches over a wide area. The impact of a large glacier sliding off a continent into the water quickly would be similar.
Add those kind of waves onto 2 meters of sea level rise and you'd have massive flooding on a global scale of most coastal communities. Even without the tsunami, most of today's coastal communities would become far more vulnerable to catastrophic flooding during storms. Which is probably why Lovelock suggests beefing up our defenses now, before it's too late.
It goes beyond that. Even if you assume all the CO2 we're pumping into the atmosphere has zero impact on climate, the climate is gonna change, and potentially within the lifetimes of most of the people reading this post. There's a great deal of evidence that big glaciers in Antarctica are melting faster than they're being replenished, and that some of them could catastrophically slip into the sea within the next few hundred years. We've been lucky to avoid any globe-spanning natural disasters like that throughout the past couple thousand years, but our luck won't hold forever. A lot of the defensive measures Lovelock advocates for combating climate change - like improving flood barriers on the Thames for the city of London, or perfecting methods for synthesizing food - will likely pay off even if we get lucky and all that CO2 doesn't itself contribute to a great melt.
For example, what happens if the Yellowstone Supervolcano blows? You could have crop failures for years, not just in the US but elsewhere around the globe. That might do more than suspend democracy - it could suspend civilization. An ability to synthesize food could come in very handy in such a situation (unless you want to unwillingly become Soylent Green for some starving mob).
It seems to me that what Lovelock is arguing is that the science tells us there are these threats, these global threats to the security of our civilization, and that we should be planning for them accordingly now while we can so that we don't have to cope with them entirely unprepared if/when hey do roll around.
He's also making assumptions, like "when a major war approaches".... who says major wars are needed, ever?
Where does Lovelock assert that major wars are needed, ever?
That's right - he doesn't.
He merely observes that when major wars approach, democracies have tended to suspend at least some of their standard peacetime practices. I fail to see how this observation could be remotely controversial, as there are innumerable examples to be drawn from the histories of the major western democracies.
he's not calling for an end to democracy. He's simply telling everybody they'll be sorry if they don't listen to him.
It's a little more complicated than that. Reading the entire interview, I think it would be more to the point to say that Lovelock is a strong advocate of having contingency plans in place at least to cope with climate change, especially involving coastal defenses against flooding. He also brings up the subject of having the capacity to manufacture synthetic food, probably to deal with crop failures brought on by sudden (or even prolonged) climate-related catastrophes.
Is that what he's saying? Or is he saying that when the climate sh*t hits the fan, governments may start to put democracy "on hold" while they attempt to deal with it? If you actually read what he says in the interview, his focus is more on what we can do in terms of disaster preparedness than on reducing carbon emissions.
If, for example, the Pine Island Glacier in Antarctica catastrophically slips into the ocean, creating tsunamis and raising global sea levels by about 2 meters overnight, who knows what governments will end up doing in response. I suspect a lot of it would involve the at least partial suspension of democracy as we've known it, while governments scramble to deal with what amounts to a global natural disaster, impacting many if not most coastal cities, where a majority of the global population lives or works and where at least half of the gross planetary product is generated.
Except this isn't an example of either the efficiency or effectiveness of "centralized control". Centralized control would be if the government operated its own testing labs and certified itself whether products are Energy Star compliant or not. Instead, they're relying on the private sector producers of the products themselves to supply their own data, with entirely predictable results.
If something can interact with things in our universe then it is in our universe
That's how you're defining the universe. That isn't the only definition of the universe, or rather, of our universe. You could have matter in two or more separate universes which can never physically interact apart from a force or forces which can bleed between universes. So maybe (some) gravity leeches out, but not EM, and matter from one universe can never physically enter the other.
String theory predicts multiple universes. And there's growing observational evidence to back up the assertion that other universes could be acting upon our own. Google "dark flow", for example. Check out the New Scientist article from Jan 23, 2009 - here's a quote from it:
Many cosmologists are happy to relegate those other universes to that dusty corner of theory where unobservable by-products are stored. Mersini-Houghton is not one of them. She argues that the dark flow is caused by other universes exerting a gravitational pull on galaxy clusters in our universe. She and her colleagues calculated how other universes, scattered at random around our bubble, would alter the gravity within it (www.arxiv.org/abs/0810.5388). "When we estimated how much force is exerted on the clusters in our universe, I was surprised that the number matched amazingly well with what Kashlinsky has observed," she says. "I firmly believe that this is the effect of something outside of our universe."
Other universes, if they exist, cannot interact with ours.
That's an assertion, but we don't know this for a fact. "Dark matter" may in fact be evidence that other universes do interact with our own. So maybe gravity isn't (entirely) bounded to the universe it originates in.
Or maybe what we consider the "visible" universe is just part of a much, much larger structure.
90% of the matter in the Universe is in a form that emits no light, but affects other matter through gravity.
Do we know for certain that the "dark matter" itself - whatever it proves to be - is actually in our universe? Is it possible that "dark matter" is just regular matter in some other universe(s) whose gravity is bleeding into our own?
We'll just have the Logopolitans open a charged vacuum emboitment to E-Space. Entropy problem solved!
Others have speculated that a megatsunami - possibly caused by the collapse of a volcanic island during an eruption or even a meteorite / comet strike - could have been the origin of the flood myth. It's interesting to note that many civilizations around that part of the world apparently shared the myth of a great flood.
I suppose it's also possible there were several different flood events that got melded into one great flood myth.
That's what the RIAA EQ curve is for. The bass is attenuated at recording and enhanced at playback.
The RIAA curve was an attempt to mitigate the problem - it does not solve it. As I already pointed out, there's really only one way around it - have your mastering engineer screw with your material until it fits within vinyl's limitations. You can reduce the amount of tweaking that needs to be done by placing only one or two songs on a 12" 45RPM EP or single, half or quarter-speed mastered, but even there vinyl doesn't have the unlimited bass capacity of CD. And I don't think most people want to buy 4 or 5 vinyl discs just to get the same material that would fit totally unaltered on a single CD!
LPs contain frequencies from subsonic to supersonic.
Yes, they can, but when it comes to subsonics, not anything at volume - certainly not on an LP. The grooves can't be wide enough if you're trying to fit 20 minutes or more onto a side. And a good portion of that subsonic and ultrasonic material is noise and distortion not present in digital media (or even other analog media, like cassette and VHS Hi-Fi).
In short, son, you have no idea what you're talking about. You obviously never even heard of the RIAA equalization curve.
Wait a minute - you just claimed that the RIAA equalization curve allows LP's - not just vinyl, but LP's - to record loud low frequency bass, and then you have the audacity to tell me that I don't know what I'm talking about? Why do you think vinyl required such careful mastering to begin with if the freakin' equalization curve automatically took care of everything?
Dolt.
The recordings had more bass because the original performance had more bass.
A lot of those performances with that kind of bass couldn't have been distributed, at least not as LPs. Both the boom car hip-hop craze and house music really took off here in the States once music distribution switched to CD and suddenly everyone could have club bass in their home or car without being forced to buy nothing but 12" singles and without having to shell out a fortune on turntables and preamps.
Rumle is virtually nonexistant on even a moderately good table.
A nice audiophile table like the Music Hall MMF 2.1LE - which goes for around $500 - sports rumble of -70dB. Note this doesn't include the rumble recorded on the record as it was mastered, or other low-frequency noise caused by the needle scraping thru the groove and especially into the walls of the leading edge of the groove. If you consider -70dB "virtually nonexistant", I suppose you also don't care about all those hypersonic signals that are supposedly so important, many of which are down at -70dB and below.
I'd just like to add here that you can get rumble of -infinity from a $50 CD player.
Oh, and I hope you weren't planning on playing your music very loud. You do know that the turntable, platter, pickup and the record itself all act like a giant microphone, right? They absorb and transmit whatever bass frequencies they're exposed to right back to the needle, in the worst instances resulting in a nasty blast of feedback. This is yet another ridiculous vinyl limitation that CD doesn't suffer from.
I'm not even going to bother reading the rest of your ill-informed comment, the ignorance is painful to my brain.
Sorry, dude. I apparently poured too much accurate information into your brain for it to handle. I guess you overloaded and skipped a groove, kinda like vinyl. My bad! Maybe I shoulda mixed everything to mono first so you could take it!
I haven't even brought up all the issues caused by the RIAA equalization curve. Suffice to say, when CD's rolled out the vinyl lovers were all in a tizzy over the brick wall filters that the CD format utilized above 20kHz to avoid Nyquist issues with 44.1kHz digital recording. Oh, it was awful, they wailed. The sound is so colored by those terrible brick wall filters, which supposedly caused phase issues and colored the sound and resulted in cats sleeping with dogs. All because that awful brick wall filter was sitting up there at the high end of the audio spectrum.
Well, guess what, kids - the RIAA equalization curve is about as dramatic, runs across the whole damn audible spectrum instead of being confined to the far upper range of human hearing, and creates a host of issues of its own. For starters, since the amount of equalization varies with frequency, there are all sorts of nasty phase and distortion issues that crop up. Also, because no two analog circuits are quite the same, there's gonna be variation between the encoding done on the master and the decoding done by your preamp. There goes fidelity right out the window!
I mean, it's a neat hack to overcome both vinyl's total inability to handle loud bass (which is deemphasized by a maximum of 20dB on recording) and to drown out high-frequency noise (high frequencies in the material are emphasized on recording by about 20dB), but it also does nasty things like enhance rumble and make good cutting heads more costly to produce (to handle such a hot high-end signal). It ain't exactly high-fidelity, but it beats grandpa's 78's on his Victrola.
EQ and compression!
No, I just pulled up the track in Goldwave to have a look. There's a ton of very low frequency signal, the kind of signal that would be difficult or impossible to record on vinyl. That kind of loud deep bass went from being an anomaly to being commonplace in the span of a couple of years once CDs were widely adopted. You might be able to deliver something approximate to it as a 12" vinyl single with very careful mastering, but you certainly couldn't just record that exact kind of material on a vinyl LP. You'd wreck the equipment! Whereas with CD, you could deliver it to millions on a 74 minute recording, no babysitting, no tampering required.
bass reproduction is not so constrained by the playback media as the playback equipment.
Well gee, the same thing is even truer for ultrasonics, yet that hasn't stopped the vinyl brigade from hyping vinyl's supposed superiority above 20kHz for the better part of two decades. At least most people can hear and feel bass down to 20Hz. Virtually nobody can hear whatever ultrasonics vinyl manages to record.
I can hear a discernable difference to the harmonics of many instruments if I apply a 24db/octave low pass filter at 16k and I've played in rock bands for 20 years.
Yeah, but CD goes up to 20kHz, and does so without all of the noise, phase issues, and equalization / re-equalization issues of vinyl (did we discuss the distortion caused by the application of the RIAA equalization curve yet?). If you apply a filter at 20kHz do you notice much of a difference?
Thus, the surface noise and distortions inherent with vinyl conspire to make something like the Who's My Generation sound fucking awesome on 7" vinyl. By comparison, that same track sounds relatively dull and lifeless on CD.
Is it the noise and distortion? Or did somebody just do a shitty job mastering the CD? I have multiple copies of some records on CD which sound radically different, depending on how they were mastered (and what they were mastered from, for that matter).
Wrong. The RIAA curve doesn't prevent loud low bass - especially stereo bass pans - from flipping the needle right out of the groove. That's because vinyl can't handle loud low bass - it's physically incapable of it. What do you expect from a format that was created a hundred years ago for anything BUT high fidelity? Mastering engineers have to ride the gain, mix to mono, vary the track pitch and pull all sorts of other tricks just to cut any record at a decent level - it's still very much an art and not entirely a science.
Can you get loud low bass onto vinyl? Sort of. If you work at it hard enough. You have to mix it to mono, attenuate the deepest loud frequencies, and then cut a 45RPM 12" on heavy virgin half speed mastered vinyl. Note that none of this is exactly high fidelity - you're jacking with the original recording in order to squeeze it onto vinyl. And even then, assuming you can cut the thing without destroying your equipment, you run the risk of the record being unplayable on some turntables. So, mastering engineers tend to be pretty conservative, which just further butchers the material.
CD doesn't have any of these ridiculous limitations. You can record as much loud low bass - or screeching treble - as you want, until it clips just like any other signal would. You'd probably blow up a lot of folks' speakers that way if you took it to the extreme, but the disc itself would still play just fine.
I won't even go into all the crap mastering engineers have to do in order to keep high frequencies from frying a lathe's cutter. Let's just say there's nothing remotely high-fidelity about vinyl and leave it at that.
String, reed and brass instruments all have harmonics and overtones extending well beyond 20k.
Faint overtones, which the microphone may or may not have been able to pickup at even lower levels, due to the rolloff in response in most audio equipment above about 20kHz. And even if the mics did manage to pick up an audible amount of those overtones, did the console filter them out? Did the tape deck record it? Did the vinyl mastering engineer cut them off, in order to reserve vinyl's limited capacity for high-frequency signals for stuff that's more audible? Can your own pickup and amp reproduce them? Your speakers? Most speakers rolloff steeply over 20kHz - combine that with the rolloff from most microphones and you've suppressed high frequency signals so much they're completely inaudible. Assuming they were ever audible over all of vinyl's high-frequency noise to begin with.
The 9db rule is that sounds of the same and nearby frequencies are masked, not that energy in the 15k region masks 20k.
That's not entirely true. The acuity of our hearing decreases as you approach the upper limits of its range. We even have a very hard time differentiating between noise and signal, especially once you get up around 20kHz or so. Unless the material is absolutely saturated with signal up there, you can swap an equal amount of one for the other - especially up above 18kHz or so - and it's awfully hard for listeners to tell the two apart when there's substantial signal present at other parts of the spectrum. (Shaped noise obviously, not constant noise which would be apparently different - but which can also add an air of space to a recording).
Try that down at 1,000Hz!
So all this arguing over the near-ultrasonic performance of various audio formats is like arguing over how many angels can dance on the head of a pin. Half the audience is stone deaf over 18kHz anyhow, and most of the rest can't tell the difference between 18kHz noise and 18kHz signal. Clearly, whatever stuff is or isn't being recorded and reproduced up there isn't terribly important compared to the rest of the audio spectrum.
u87's roll off from 15-16k, to about -9db at 20k. There's actually a slight peak around or slightly above 20k because it's the first harmonic of the resonant frequency of the diaphragm (which is around 10kHz).
The manufacturer claims 20kHz as the limit, last time I checked. Any harmonics being generated may not actually reflect program material the microphone was intended to record, but are instead harmonic distortion being generated by the diaphragm. One more reason to discard frequencies outside the range of human hearing - the recording and playback equipment we use is capable of throwing more signal than noise at those frequencies, so why rob amplifier power and tax your speakers to playback a bunch of noise and distortion? Better to reserve all that for linear performance in the audible range.
Ignoring that cymbals are rarely mic'd directly and that I've never seen SM57's used for drum overheads because the mechanical action of the microphones coil would damp high frequencies
Oh really? Because a quick Google of SM57 drum overhead reveals about 115,000 hits. Larry Mullen is apparently using them for overheads on U2 records, from what I could find on Google. The Red Hot Chili Peppers apparently record just about everything with SM57's, even vocals. Maybe they want the high frequencies dampened a bit. Imagine that! (Probably can't hear 'em anymore, anyhow.)
The frequency response of mics does not "top out", it slopes off.
Yes, and often it slopes off dramatically, which is what I'm referring to when I say, "top out" - the point at which it stops being fairly flat and goes into obvious, often dramatic decline. The same thing happens with speakers. Between the rolloff in the mic's response and the rolloff in your own speakers' response, it's entirely likely there's no audible, intentional signal presen
A lot of the articles I read on the subject in the past were either in magazines, or are gone from the web now. Mix magazine has an article which touches on some of vinyl's limitations:
http://mixonline.com/ar/audio_witch/
Apart from that, check Wikipedia for articles regarding stuff like the RIAA equalization curve, or just Google the specifications for things like microphones and analog tape decks. You'll quickly discover that a lot of the "high frequency" information some audiophiles claim to be hearing can't possibly have been intentionally recorded. In other words, it's noise.
The following comes from an old April issue of Audio Magazine. It cleverly points out some of vinyl's many failings:
NEW PRODUCT ANNOUNCEMENT
The LIRPA-1 CD Enhancer/LP Record Simulator:
A revolutionary new device for all those who believe that CD players
produce "mid-fi" results, and that analog recordings (LPs) are superior
to CDs.
PURPOSE:
This device allows you to tailor the signal produced by the
Compact Disk medium to more closely resemble that of LP records.
It can be placed between the Compact Disk player and your
receiver, in a tape monitor loop or external processing loop, or
between the preamp and power amplifier of your stereo system.
STANDARD FEATURES:
o HARMONIC DISTORTION GENERATOR: Adjustable from 0% to 100% THD
(total harmonic distortion). This allows you to increase the total
harmonic distortion of the Compact Disk from 0.01% to levels found
on typical LPs played with "top-of-the-line" stereo cartridges
(commonly 1% THD +). An additional benefit is found in that this
control also contributes to that ultra-sonic information above
22kHz which was "lost" in the digital process.
o SEPARATION-REDUCTION CONTROL: Permits variable blending of left and
right channels over a range from 90dB separation (found on Compact
Disks) to full blending (monophonic sound). Adjustment of about
30dB separation is recommended to simulate the typical "state-of-
the-art" stereo cartridge.
o DYNAMIC RANGE COMPRESSOR: Now you don't have to worry whether your
power amplifier or your speakers are "Digital-Ready". This knob
allows you to reduce the dynamic range of the Compact Disk from
90dB to as low as 45dB. This is a definite "must" for those who
prefer the TELARC 1812 LP to the TELARC 1812 CD (suggested adjustment
for this recording: 65dB).
o SUB-SONIC DOPPLER DISTORTION GENERATOR: Superimposes sub-sonic