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Comet To Make Close Call With Mars

wisebabo Not on human timescales (44 comments)

While the solar wind will blow away the atmosphere in a (perhaps) short time geologically speaking, in a human timescale it would likely take thousands of years. By then, the humans could have implemented a giant electromagnetic shield (powered by sharks with frickin lasers) or have developed wormholes to directly transfer water from the water from Jupiter's moons or have migrated to the far reaches of the galaxy. Or have gone extinct.

Mars didn't become the dry desert it is today in an instant, I believe for the first half billion years or so it was a warm wet place (because of the cometary impacts during the chaotic early solar system. Hence all the evidence of flowing water). Plenty of time.

By the way, responding to other posts, it is very easy to move satellites great distances in orbit GIVEN TIME. A simple 1m/sec change in velocity would, after a month, result in change in distance of several thousand kilometers. Remember that these spacecraft are capable of quite substantial delta-vee changes (in the KILOmeters/sec). And that isn't even taking into account any kind of sophisticated planning by the mission controllers (like using gravity assists or chaotic gravitational effects "the interplanetary highway").

3 days ago

Comet To Make Close Call With Mars

wisebabo Too bad this didn't happen in 50 years (44 comments)

If this happened (optimistically) 50 years from now, we'd be able to deflect the comet to HIT mars, thus delivering a lot of water and warming things up a bit. (Only, I'm afraid, a little bit of terraforming, it would probably take thousands of such comet strikes to make the planet "habitable"). Or we could make it hit one of the moons and, if done very carefully, could deliver said water to possible Mars Moon colonists (but they'd have to find a way to keep the resulting fragments from ruining near-Mars space for space travels).

More realistically, I wonder if NASA (and the ESA) have plans to move their spacecraft for best viewing. If they're worried about damage, they could have them be on the other side of the planet when it makes its closest approach. If there are any spacecraft that are on their "last legs" (low propellent, malfunctioning equipment, no more spare reaction wheels), perhaps they could even make a very risky close approach!

I expect there will be some great images! (If the HiRes camera on the Mars Reconnaissance Orbiter can take 1m resolutions of Mars from orbit, it surely will be able to take great pictures of a comet only a few tens of thousands of kilometers away).

3 days ago

Cosmologists Show Negative Mass Could Exist In Our Universe

wisebabo OMG! A (possibly) testable theory! (214 comments)

Before I read the article, I'd have been predisposed to agree with the poster who called this "The crackpot cosmology theory Du Jour". However the article does note that not only does negative matter possibly explain the current lack of detection of gravitation waves but (presumably unlike many other phenomena) predicts that if there is negative matter, we WOULD be able to detect gravitational waves but only above a certain frequency:

"the evidence that could back it up would be the discovery of the threshold frequency above which the waves do propagate"

If anyone who can read and understand the actual paper could tell us non-cosmologists when our improving technology might be able to detect gravitational waves above the cut-off frequency I would appreciate it. I mean is it technology that is (very roughly) 10 years away, 25 years, a century or basically only when we have god-like powers. I seem to remember that NASA was going to launch a space based interferometer with "arms" (free floating platforms) in a triangle 5 million km on a side. Would that be able to detect them? The whole point now isn't just to prove the existence of gravity waves but also negative matter (and the possibility of warp drives, yay!).

Actually, since (if I am reading the article correctly) they are looking for "higher frequencies", doesn't that mean the detectors should be smaller? ("arm" length shorter?) Shouldn't they be increasing the sensitivity instead? Or is the sensitivity increased by making the detector larger? I'm so confused!

about two weeks ago

Swedish Farmers Have Doubts About Climatologists and Climate Change

wisebabo Many(?) Swedes vs. Millions of S.E. Asians (567 comments)

So while I'm not ready to completely discount the stories of some Swedish "focus groups" (from the article), that anecdotal evidence would be balanced (overwhelmed? flooded? washed away? submerged?) by the experiences of tens of millions of rice farmers here in S.E. Asia (Mekong delta) who are literally seeing their future disappear before their eyes.

I think the rate of inundation by the ocean here (I live in Vietnam) is getting ridiculous, I frequently read in the local papers about KILOMETERS per year of rice paddies being lost to the sea; if not by direct submergence then by saltwater infiltration. I don't think there's a shadow of a doubt to these farmers that SOMETHING very bad is happening, though honestly I'm not sure if many of them have even heard of climate change.

Now of course there are a lot of other things going on that could be contributing to this. Overuse of groundwater, damming of the Mekong, improper irrigation; I'm not a climate scientist and I haven't screened out those effects (of course climate scientists who've looked at this closely have and they say the effect is real). But neither are those Swedes climate scientists so if their unprofessional opinion is that nothing out of the ordinary is going on, well I've got ten times (a hundred times? a thousand times?) more opinions here to counter that. Then again, there just might be some biases in listening more to white europeans as opposed to brown asians so maybe their opinions don't count. (I rarely if ever see any articles in Western media about the tremendous loss to agriculture that these farmers in the Mekong are facing; the rice basket to HUNDREDS of millions of people; nor do I see articles about the gloomy forecasts made by the governments here that in 20 years or so millions of people in cities like mine, saigon, will be flooded out).

about a month ago

Automated Remote Charging for Your Flying Drones (Video)

wisebabo This is probably illegal but... (30 comments)

I thought they meant WIRELESS automated remote charging. Like as in a laser or microwave beam transmitting power to a drone to keep it flying indefinitely.

I was wondering how much power it would require to keep a relatively small drone (but still capable of carrying a decent camera and transmitter) aloft. Of course the drone would have to be equipped with some sort of receiver capable of converting the beamed energy (visible light? IR? microwave?) into electricity. By "power" I'm referring to the power of the beam as well as the power fed into the transmitter (more because of losses).

Would there be a 10:1 ratio of power fed into the transmitter: power converted into electricity? 2:1? 100:1? I assume the beamed power would be way beyond what is regarded as "safe", certainly for a visible light laser maybe not for microwave. (That's why I assume it would be illegal). On the other hand, I assume a reasonably simple pointing system on the ground station could illuminate the (not too big) receiving antennae on the drone and would be able to compensate for sudden gusts of wind, etc. Of course the drone would have a small reserve battery.

What would be the effective range for a (practical) system? 100m? 1km? 10km? Anyway, it could be an excellent observation/surveillance platform. Imagine having a permanent camera flying (lazy circles?) above your house. Maybe if it was robust (and safe!) enough, power could be beamed BETWEEN drones (or even from orbit) thus getting rid of any range restrictions. On the other hand, if the tracking was really good, perhaps the "ground" station could be mounted on a moving vehicle; that might make the kind of flying companion drone, as seen on the cartoon "Speed Racer" where we have a robotic bird following the car, practical.

A really sophisticated long range drone might even have power AND communications beamed on a tight microwave beam from a (BIG) antennae in geo-sync orbit. Being able to loiter at almost any altitude over any area for any length of time might make this very valuable to the military (And a big drone could, of course, carry weapons). On the other hand, if the transmitter/receiver/converter overhead wasn't too large, it could be used in the exploration of other worlds. NASA was recently talking about having a quadcopter drone combined with a balloon in Titan's atmosphere; the drone would have to periodically dock to recharge its battery from the nuclear generator on board the drone. Well, this would allow the drone to keep flying without docking.

about a month ago

Elon Musk: I'll Put a Human On Mars By 2026

wisebabo Evolution in action! (275 comments)

Since we don't know what the long term effects of low-gee gravity (Mars is 1/3 that of Earth) as well as the higher level of background radiation (Mars' atmosphere is too thin to screen out a lot it), we're going to be evolving a new race of Humans! (I guess we'll call them Martians).

This is the way Nature has done it for billions of years and it's worked. It's called Evolution. Sounds fine except Evolution works through DEATH, DEATH killing off those who can't survive long enough to pass along their genes to the next generation. So we may find that the first generation of colonists on Mars are going to have an absolutely horrific death rate (in addition to all the problems they'll run into with accidents, running out of supplies, breakdowns, etc.) but the next generation will be less so and so on. This is not a pretty picture but then again Nature; "red in tooth and claw" rarely is.

The only way to make sure that there are enough Humans to evolve into Martians is to have a very high birth rate. So perhaps, as Dr. Strangelove would have it, we should have a wildly disproportionate sex ratio of females to males, in order to have the maximum population growth ("and they should be of a highly stimulating sexual nature" :). So maybe there's something in it for (men) to go to Mars!

Of course we could actually avoid all this trauma (and sex?) by avoiding the natural selection process of Nature by fully understanding the problems we will face. Then we could either, pre-select the individuals who happened to be genetically endowed to survive and reproduce under those conditions or genetically engineer people who can. But that would actually require spending (comparatively little) money on such things as a centrifuge for the ISS to study mammalian reproduction under partial-gee situations. Since our species is not particularly good at planning (climate change anyone?) it appears as if we may be colonizing the old fashioned way; send a lot of people and see who lives.

I think the first polynesians to cross the pacific in their canoes, the first americans to walk across the bering strait and even the first pilgrims to land in New England (1/3 died the first winter) would sympathize.

about a month ago

Chinese-Built Cars Are Coming To the US Next Year

wisebabo Don't buy Chinese (if you can) (431 comments)

About 5 years ago I stopped investing in Chinese companies. Why? Because I didn't want to support even indirectly a regime that, without apology, oppressed Tibet and supported the despotic regime of North Korea. I hold them largely responsible for sacrificing millions of my long-separated brothers (yes, I'm ethnic Korean) through starvation and torture simply to keep a "buffer state" in between them and the "capitalist" (ha ha, what irony) South Korea and U.S.

My stance was only hardened by their support, for purely geopolitical/economic considerations (OIL), of Syria and Iran (and, I think Libya). They and Russia have kept those regimes propped up and have made the tragedies in the Middle East even worse (of course America started it but at least we know now that most of us were idiots to be led by one). That's not to mention the authoritarian and despotic regimes that China is supporting in Africa purely for their resources.

Look, I know the West (and especially the U.S.) have done a LOT of bad things but the Chinese don't even make a pretense of things like human rights, even in their own country. As I've said, they've been willing to sacrifice millions for a modicum of security (they could've asked the U.S. and S. Korea if, in return for not letting the Kims return to North Korea from one of their trips to China, we would promise not to put American troops north of the 38th parallel. As if S. Korea would even want American troops on the peninsula once the threat was gone). Now, living in S.E. Asia, I see firsthand how China with its growing power is throwing away treaties and agreements it has signed in order to bully the Vietnamese and Philippines with their ridiculous "cow tongue" shaped demarcation of the seas. They are returning to 19th century "gunboat" diplomacy in the 21 century world.

I fear that as China grows ever stronger, they will continue to discard previous commitments to peace and will literally force their will upon the world. Is that what you want to support? I'm a realist, and I love my gadgets and my improved standard of living brought on by the flood of low-cost Chinese products (often produced with stolen patents and technologies but that's another story) and I'm not quite ready to live without. However, when there's a choice, when you can purchase something that is identical (hopefully) in every way including price to another but one is made in China and one was made in Sweden(?), I hope you'll make the same choice I do.

If China, not the U.S. had the power the NSA has; would any of us have any protection at all? Think of what kind of world that would be to live in. (That's what 1.2 billion people ARE living in).

about a month and a half ago

Getting the Most Out of the Space Station (Before It's Too Late)

wisebabo Yes, I agree, here's my previous post (155 comments)

What level of gravity do humans need to THRIVE for long periods of time? (That is so that they do not suffer from bone density loss, cardio-muscular problems, etc.) Is it 1/6 gee (moon)? 1/3 gee (mars)? Or will humans need a full 1 gee to live and, eventually, safely REPRODUCE?

If the answer is humans need a full gee, then we might as well just resign ourselves to limiting our trips into the solar system to quick jaunts and robotic explorers. (While you *might* convince colonists to spend say an hour a day doing exercises to maintain their health, no way would you be able to make a fetus do them). We'll need to re-engineer humans before we can make a serious effort to colonize another world. (The only rocky planet with anything near our level of gravity is Venus and it is a hellhole). That's why the loss of the centrifuge planned for the ISS that would examine the effects of "partial gravity" (as opposed to the "micro-gravity" the ISS currently has or the regular gravity that we have) on biological systems was so disappointing. Literally it would have told us whether or not colonization of space was really feasible in the near future. (It probably wasn't going to be big enough to hold people but just seeing how partial gravity affected laboratory mice would go a long way to answering these questions).

Perhaps if we can dump the Ruskies, with the money saved with using Space-X's rockets we could build a decent centrifuge to make these (literally) VITAL studies. Maybe we don't even need to attach it to the ISS; just take two of Bigelow's(?) inflatable habs, add a cable and spin! (Just by changing the cable length you could alter the g-forces so no additional propulsion other than the initial thrusting would be required). But that's the deluxe model, you could just take the Dragon capsule and have a cable attached to its spent second stage and spin THAT (the center of gravity might not be in the "middle" but it should work fine). Keep it in orbit for a few generations of mice and dissect them when they return.

While we're at it, we should probably look into circadian rhythms... (but maybe mars, with it's 24-1/2 hour "day" is close enough).

about a month and a half ago

Moon Swirls May Inspire Revolution In the Science of Deflector Shields

wisebabo Next up: We need a centrifuge in orbit! (76 comments)

That's great! (No really: I'm not being sarcastic, that gets rid of one of the two great barriers to deep space travel and living on all the planets not-as-large-as-the-earth).

The other BIG problem is: What level of gravity do humans need to THRIVE for long periods of time? (That is so that they do not suffer from bone density loss, cardio-muscular problems, etc.) Is it 1/6 gee (moon)? 1/3 gee (mars)? Or will humans need a full 1 gee to live and, eventually, safely REPRODUCE?

If the answer is humans need a full gee, then we might as well just resign ourselves to limiting our trips into the solar system to quick jaunts and robotic explorers. (While you *might* convince colonists to spend say an hour a day doing exercises to maintain their health, no way would you be able to make a fetus do them). We'll need to re-engineer humans before we can make a serious effort to colonize another world. (The only rocky planet with anything near our level of gravity is Venus and it is a hellhole). That's why the loss of the centrifuge planned for the ISS that would examine the effects of "partial gravity" (as opposed to the "micro-gravity" the ISS currently has or the regular gravity that we have) on biological systems was so disappointing. Literally it would have told us whether or not colonization of space was really feasible in the near future. (It probably wasn't going to be big enough to hold people but just seeing how partial gravity affected laboratory mice would go a long way to answering these questions).

Perhaps if we can dump the Ruskies, with the money saved with using Space-X's rockets we could build a decent centrifuge to make these (literally) VITAL studies. Maybe we don't even need to attach it to the ISS; just take two of Bigelow's(?) inflatable habs, add a cable and spin! (Just by changing the cable length you could alter the g-forces so no additional propulsion other than the initial thrusting would be required). But that's the deluxe model, you could just take the Dragon capsule and have a cable attached to its spent second stage and spin THAT (the center of gravity might not be in the "middle" but it should work fine). Keep it in orbit for a few generations of mice and dissect them when they return.

While we're at it, we should probably look into circadian rhythms... (but maybe mars, with it's 24-1/2 hour "day" is close enough).

about a month and a half ago

Robots and Irradiated Parasites Enlisted In the Fight Against Malaria

wisebabo I would be willing to donate IF... (84 comments)

... I could be a part of the next clinical trial!

I'm sorry if this sounds too self-centered but assuming that the vaccine has been proven to be safe (I'll take the risk that it might not be effective), I'd be happy to make a donation of a few hundred dollars to be one of the first people to receive it. (I live in a part of the world where I could get malaria). I figure that if I paid a lot more than they expect the final vaccine to cost (there's no way they'll be able to reach hundreds of millions of people in the third world if it's more than a few bucks), I would be helping to accelerate the development of said final vaccine. I think it's only reasonable that I be permitted to get it sooner!

Again, sorry for the "elitist" I want it first attitude but in this case, the early adopters like me would make it possible to save many more lives in the process. And, I don't know too much about these kickstarter campaigns but isn't that typically what donors get in return for their advance payment, to be first in line to get the finished product? Here I'd be doing the same but paying many times the (hoped for) final cost!

about 2 months ago

US May Prevent Chinese Hackers From Attending Def Con, Black Hat

wisebabo Why doesn't the U.S. STRIKE BACK?!!! (193 comments)

Ok, the U.S. (through the NSA) has been revealed (through Snowden) to be able to:
1) record and retain EVERY phone call made in an ENTIRE country (actually two, the Bahamas and Afghanistan I think)
2) hack into the e-mail of at least some world leaders (for example: Germany, not exactly weak in the technology department)
3) subvert (and exploit?) the standards for some of the world's most widely used security protocols
4) hack into the networks of Huawei to view source code (and change it?), one of the largest vendors of routers and other critical network gear
5) collect and retain for later data mining, the text and metadata for hundreds of MILLIONS (billions?) of people for YEARS
6) record conversations, videos and other intel through devices even when they appear to be OFF
7) has planted HARDWARE back doors in the equipment used worldwide for computing and communications
and on and on...

So why can't they tell China to STOP HACKING our networks for business advantage or ELSE
1) release the e-mails and other documents showing the favors given to the families of the top Chinese officials
2) publish the electronic money trail where the HUNDREDS OF BILLIONS of dollars worth of bribes have gone (at that scale you don't use scraps of paper)
- this includes MONEY and other assets like property illegally squirreled ABROAD, which may be an offense (under Chinese law) punishable by DEATH
3) publish information regarding kept mistresses of the marriage officials of the elite, their names, dates of assignation, children born out of wedlock, assets
- throw in pictures (videos?) and every tabloid would have a field day
4) detail the political "assassinations" (sometimes literal!) and other dirty deals the elite have done to get into and remain in power

It appears that as a byproduct of their goal(?) of ferreting out security threats to the U.S. (or just plain building their capabilities) the NSA has a treasure trove of information that could topple MANY corrupt, authoritarian governments. Of course the U.S. is not immune to corruption but (I read) the (illegal) corruption in the U.S. is measured in the millions not billions of dollars. That's to be distinguished from the legal forms of corruption, lobbying, that plagues the U.S. :(

The NSA, starting from WWII, has had many decades (and a budget in the tens of billions A YEAR) to build up their technological supremacy (as well as being the single largest employer of mathematicians on the planet. Think of what THAT means). That is not an insignificant amount of money, it DWARFS most countries entire defense budgets! Also remember that the U.S. (and to a lessor extent Britain) are the CREATOR of the Internet as well as the modern computer; remember that Google, Microsoft, Facebook, Twitter, Apple, Cisco, Intel, IBM, AMD, ARM, Nvidia are all Anglo-American companies. Think of all the "backdoor" connections that have been made over the past half-century at informal (high school/college buddies), formal (legal demands for information) and top secret levels (matter of national security or else go to prison). It's at the point where, to a foreign government, every CPU made or designed in America (basically all of them) and every packet (sent from America) must be suspect.

So the Chinese have MUCH much more to fear from the U.S. If they don't want a "digital Pearl Harbor" they would be wise to play by (America's) rules.

about 2 months ago

Is It Really GPS If It Doesn't Use Satellites?

wisebabo Re:How new is this? (298 comments)

You may very well be right, I mean I saw this article when I was just a kid which puts it way way back (cuban missile crisis anyone? :) There was no laser ring gyroscopes back then (I remember when they were invented), there was barely electricity! (just kidding).

And how does one keep a superfluid liquid in a sealed container (let alone one that is in a hopefully low maintenance solid fueled rocket in a nuclear missile submarine that is then subjected to the forces of an undersea launch and boost phase)? My skepticism meter wasn't nearly as sensitive back then but now I wonder. Can a superfluid liquid even STAY in a sealed container for long if it wants to get out? (I remember that superfluid liquid helium can climb the walls of its vessel as well as squeeze through microscopic pores).

Oh well, the picture was cool looking, like something out of "Akira".

about 2 months ago

Is It Really GPS If It Doesn't Use Satellites?

wisebabo Mod parent up! (298 comments)

He's right! I'm sorry, I don't know which is wrong, if the isotope of Helium that is used for superfluidity is Helium 3 or something or if it is not so scarce.

My bad.

about 2 months ago

Is It Really GPS If It Doesn't Use Satellites?

wisebabo How new is this? (298 comments)

A long time ago I saw something that (according to the caption on the photo) was an inertial guidance unit for SLBMs. It was an instrumented(?) sphere that floated in liquid helium 4 which, at that temperature, was a superfluid (which I guess is a kind of quantum effect). This was to compensate for the motion of the submarine AND the flight of the SLBM because in a nuclear war I guess you can't count on any external sensors like a star tracker working. Since this sphere was suspended in a frictionless fluid presumably any frictional losses would be zero (and I guess very precise accelerometers could do the rest).

Now that I think of it, this might have been B.S. (how does one keep liquid helium 4 a liquid in a device, a solid fueled rocket, that you don't want to have to keep constantly maintained?). Still, "maybe" it actually worked, in which case why don't they just use this system in the sub? Are the running out of helium-4? (I think it's a rare isotope of a scarce gas).

about 2 months ago

NASA's Plan To Block Light From Distant Stars To Find 'Earth 2.0'

wisebabo 3D "Prickly Pear" instead of 2D "flower"? (92 comments)

That's what I meant in my original post by having a (very) corrugated sphere. But maybe a "prickly pear" or "cactus" or "sea urchin" shape would be better.

Anyway, the diffraction questions are way beyond my (non-existent) knowledge of optics. Anyone care to chime in? How about using a coating of the new "magic" meta-materials? (Not that I have any idea of that could solve anything).

Just trying to think outside the box.

about 2 months ago

NASA's Plan To Block Light From Distant Stars To Find 'Earth 2.0'

wisebabo Can they make a 3D shade? (92 comments)

What I mean is, instead of a shade that looks like a "flower" with "petals" can they make something that looks more like a (very) corrugated sphere?

That way if the spacecraft maneuvers to a new position relative to it, it won't have have to rotate (making it much less complex with no active mechanisms required). Also, multiple telescopes could simultaneously use it from different angles.

It could be a simple inflating balloon (perhaps with a fast setting foam) or something more complex like a "hoberman sphere"(?).

If they put it in geo- sync orbit and made it the appropriate size could multiple ground telescopes use it? With good adaptive optics of course, perhaps firing a laser at it (using it as a reference target) at a different wavelength of course for atmospheric aberration correction.

about 2 months ago

Elderly Mice Perk Up With Transfused Blood

wisebabo Not quite the "Quadrupling of life span".... (178 comments)

... that they got from another study:

but at least these mice weren't genetically engineered to only live a week to begin with so this result may have a (lot) more relevance.

Fortunately despite the worries of the (first!) poster, hopefully we won't descend into a civilization where the old literally becomes a vampiritic parasite on the young. They've already identified, isolated and synthetically produced (the?) protein which causes this effect so we'll be able to get the benefits without bloodletting. Still makes (made?) a great premise for science fiction/vampire movies.

As an aside, I'm impressed by how Harvard, a decade or two ago, seemed to make the decision not to go into (what I thought) was the trendy/hot science of genetic engineering but instead has invested hundreds and hundreds of millions of dollars into becoming the(?) center for stem cell research. Meanwhile, genetic engineering seemed to have been sidetracked by "junk DNA" and epigenetics and in general the overwhelming complexity of the human genome (although the invention of CRISPR is a major major advance). Was it obvious to biologists that this was the right decision? Go Crimson!

about 3 months ago

The Greatest 'Amateur' Astronomer You've Probably Never Heard Of

wisebabo Here, here! (or is it hear, hear?) (37 comments)

I'm not British so I don't know the correct way to spell that cheer.

Still, I just want to say, good article or bad (according to Ecuador 740021), it opened up my eyes to a remarkable individual. Especially illuminating was the photographs of the Andromeda Galaxy which shows how much his techniques improved astronomy.

Enough with the jokes. I wish to praise him, not pun-ish him. (no, really). Maybe in his case instead of "Here, here!" we should say "See, see!".

about 3 months ago

How Japan Plans To Build Orbital Solar Power Stations

wisebabo Not unless we have a space elevator (230 comments)

I'm afraid that even if Space X comes to the rescue and gives us a 2-order magnitude (factor of 100) reduction in launch costs it still doesn't make economic sense. As other posters have mentioned, why not just put it on earth? The relative lack of efficiency is more than made up for by not having to pay $$$ per kg to get it into geo-sync orbit. (However a great many cool, exciting and useful things like semi-affordable trips to space for the semi-rich and really good planetary exploration will become possible with a 2-order magnitude reduction in launch costs so let's hope that Space X can give us fully reusable launch systems!).

No, the only way this makes economic sense is if we have a space elevator (or cheap, lightweight nuclear fusion engines*, or anti-gravity, or giant swans pulling us in winged chariots to the heavens). Now there may be other applications (military? propulsion system for interstellar vehicles?) for having a large power station in geo-sync orbit but many of them don't make sense either (a simple bucket of sand at orbital velocities could do major damage to it).

*but if we have nuclear fusion, why would we need solar?

about 3 months ago

Siphons Work Due To Gravity, Not Atmospheric Pressure: Now With Peer Review

wisebabo An even simpler experiment (360 comments)

Since he had to go to some length describing the troubles he had because the low pressure formed bubbles due to cavitation, etc. (remember he could not perform this at zero atmospheric pressure because the water would boil), why use water?

Why not use a liquid that will not boil in a vacuum, like (I think) mercury? That would very easily prove that atmospheric pressure is not required to make a siphon work (because there's no atmosphere!).

Take a flexible tube and dunk it in a bucket filled with mercury letting it fill up. Now, sealing the ends, keep one end in the bucket while lowering the other end to another bucket positioned substantially below the first. Pump all the air out of the chamber and unseal the ends. If the siphon works, it is definitely solely due to gravity (remember there's no air!).

Actually, not knowing what the intermolecular bonds are like between mercury molecules, will the siphon still work? If mercury molecules have little or no attraction between them (unlike water which has very strong intermolecular bonds as seen with its high surface tension and high boiling point), perhaps it would behave like discrete particles and there would not be any siphon effect. For example, imagine the bucket and tube to be filled with sand. Would there be a siphon effect? I don't think so because the grains of sand wouldn't "pull" on each other so the sand in the tube would just run out in both directions from the high point in the tube.

Another way to think of the intermolecular bonds is to think of a coiled chain which is held aloft. If a part of it is pulled over a pulley and a substantial length is allowed to dangle down the other side, the rest will be pulled up to the pulley and then down. Of course if all the links in the chain are broken (no intermolecular bonds) then the chain will simply fall away from the pulley on both sides.

about 3 months ago



Watch celestial mechanics in (almost) real time!

wisebabo wisebabo writes  |  about a month and a half ago

wisebabo (638845) writes "If Sir Isaac Newton weren't already dead and in Heaven, I'm sure this would make him die and go there.

Here (scroll down to the GIF, please) is a time-lapse sequence taken by Cassini at Saturn of a small (okay tiny) moon "Prometheus" pulling out streamers of dust from the nearby ring over and over again. For eternity. (Or at least tens of millions of years). While the sequence only shows one such event, a quick glance at a larger scale (scroll to the top, please) shows that it is doing so repeatedly. L i k e c l o c k w o r k.

Despite all the troubles in the world (although the number of deaths due to war DO seem to be decreasing which is a minor problem in itself these kind of things make me realize that I am living in an incredible age."

Link to Original Source

Can you 3D print a custom designed airborne drone "relatively" cheaply?

wisebabo wisebabo writes  |  about a year ago

wisebabo (638845) writes "By now many of you may have seen the video of the drones (custom made?) air delivering sushi at a London restaurant. I was most impressed by the load carrying capacity (it looks like 4 "mini" rice burgers) and would love to see the control interface (it looks like it's using an iPad) as well as know what are the maintenance requirements (do they automatically land and dock/recharge themselves?).

Anyway, I'm thinking that with easy to use control software there are lots of cool marginally useful tasks a drone could do (walk your very small dog, feed the goldfish, water some cactus or bonsai trees, chase crows and yes bring you beer). Since the requirements for these jobs are likely to vary considerably (while the basic airframe may be roughly the same I can imagine all sorts of camera attachments, grippers, cargo holders), it would be great if one could design and make one of these things largely (not including motors and electronics) at home. Are hobbyist 3D printers (less than $3K) up to the task? Is the plastic material strong enough for the kinds of modest* loads one could expect? Would it take a lot of work to make critical surfaces (fan blades) aerodynamically smooth or just a little sand paper? If, I mean WHEN, they crash and break, would the cost of reprinting parts be reasonable?

I heard that a company has come out with a 3D printer that makes much more accurate prints using the laser-on-liquid method of stereolithography (and is currently being sued for patent infringement!). I also heard that someone is making "an operating system" for drones that might reduce the difficulty of writing software for these things. (I've heard it'll be expensive, hope he'll license it more cheaply for non-commercial uses). I assume that current drones could be controlled by something like the arduino computer, is it light enough? Are the electric motors and batteries pretty standard? If true and these things come to pass, could I conceivably make my own drone at home?

Of course, until there's a thriving community of people passing designs around, it'll probably be best to take an existing drone (like the Parrot AR) and first build replacement parts (what's the best way to make high precision small scale 3D scans?) and then modify it. With even this basic capability there would be many things people could try, like would it be better to have bigger but slower turning blades? More blades? Fewer? How about being able to transition to a winged flying mode for greater range? What about landing gear, recharging hookups? More sophisticated users could try modeling the aerodynamics and basic structure of the drone to improve performance, handling, payload capacity. How about making a version of the "flying bird drone" that Speed Racer had with his Mach 5?

Anyway, I have one last reason why I'd like to be able to print out (most of) a drone at home. I live in Vietnam and getting anything unusual/rare/special like spare parts for a drone takes a lot of time/money/bribery. I figure it might be better to get one good 3D printer into the country than waiting weeks every time I needed to get a spare/modified part. (I'll stockpile the feedstocks).

So what's possible now (or in the next year) and what items have I left out? GPS, cellphone module, cameras, lights, antennas, microphones/speakers for sonar? Grappling hooks? Tasers? Mace? Does anyone know the bandwidth requirements for remotely controlling/watching a video feed? (the phone network here is only 3G). How about a high bandwidth laser comm link? How about powering it via microwaves or lasers?

(Of course there are even more problematic applications that can be addressed with printing a drone at home especially if it can carry a grenade or carry a 3D printed gun!) but I won't go there now. On a side note, are drones legal to be used in paintball? Can one team use drones for surveillance or dropping/firing paint bombs/weapons? Could another team fight back using drones in aerial dogfights? Since they are so fragile and expensive for the average gamer I imagine a laser target scheme could be used where it would register a hit. You could have your own mini-arms race!)

*If the plastic is really strong, I'd love to think about making an underwater drone for exploring some of the reefs in S.E. Asia!"

Samsung, the "great imitator" (and that's in a GOOD way)

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Here's an article that looks at the Samsung-Apple battle from a Korean point of view. Yes, Samsung may be an "imitator" but it's a GREAT one. As a commentor notes, look what happened to those companies (Nokia, Motorola, RIM) that didn't imitate the iPhone, they got crushed. That wouldn't be acceptable for the "national champion" that Samsung is. At least Samsung survived, thrived and now is set to dominate the smartphone market with the Galaxy IV release after the iPhone 5.

Anyway, if so, be careful for what you wish for. A world where the winners are not innovators but rather "fast executioners"; this may lead us to technological stasis. Imagine if Samsung were able to copy DOS, we'd still be typing on C: prompts! (Admittedly the systems would be very cheap and fast).

An interesting note is just like the article mentions, my Korean friends cannot believe there would be an impartial jury (what with the trial occurring in Apple's hometown and the alleged technical incompetence of the jurors). On the other hand, my American friends find it surprising that the Korean judges presiding over Korean case might be biased (despite Samsung contributing a FIFTH of the entire economy and the CEO and underlings being convicted and imprisoned on bribery and corruption charges).

I guess people see in others what they see in themselves."

Link to Original Source

U.S., Gulf Allies try to build missile defense against Iran

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Sheesh what an engineering nightmare! To put all this together without a starting "blueprint" (unlike the Europeans) must be a real pain. Fortunately, if there's one thing those guys have it's money (and we have quite the arms bazaar they can spend it on).

Too bad Israel won't be a part of this missile shield. They could really use the information collected by the radars and sensors in these countries as the missiles fly by.

Very gradually, Ronald Reagan's dream of a "Star Wars" missile shield seems to be taking place. Of course it is only good against very primitive attackers who will likely only be able to launch by ones or twos and has required the consistent funding of billions of dollars a year for decades but hey, it's a start. Maybe if the Russians (and Chinese?) promise not to upgrade their systems, we'll be there in another 30 years."

Link to Original Source

Aerographite: the solution to space junk

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "This newly "discovered" (manufactured) material is the lightest ever created. It weighs only .2mg/cm^3.

What this means a giant "plate" of this stuff 1 km x 1 km by 1 meter thick weighing 200 metric tons could be launched by one (or maybe two) Falcon Heavy.

Aerogels have proven stopping power for hypervelocity fragments, the were used on NASAs Stardust and Genesis probes to capture particles impacting at many kilometers/second. True these particles were microscopic but this "plate" (oriented perpendicular to the direction of motion) would be a meter thick. While obviously incapable of stopping large objects, it would be ideal for stopping (or slowing which is just as good because they would de-orbit) small objects like paint flecks or even things like bolts. I contend these are the most dangerous space junk objects because it is economically infeasible to track down and catch them due to their sheer numbers.

Anyway, what really makes this (more) practical now, in addition to its light weight the material is highly compressible. From TFA: "by a factor of a thousand, only to spring back to its original size. So it could actually be squeezed into the payload bay of a Falcon and presumably pop out.

All you have to do is add a guidance system, solar panels, and ion drive to compensate for atmospheric drag, solar pressure, momentum loss from impacts and to change orbit to go after more stuff!

Oh and you've got to figure out how to make a square kilometer of this stuff at an affordable price.

(Spin off technology, ultra springy "air beds"!). Graphene/carbon, is there anything it can't do?"

Link to Original Source

THIS is what will make A.I. Possible

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "My friends in the field (academic working in A.I. and computational linguistics researcher at the NSA) says that the big stumbling block to A.I. now is not software (which is what I thought) but just that our machines are just so power hungry (electric power not ambition or at least not yet). When you think of something like Watson or the google search engine, you realize that is comprised of thousands of machines running millions of processes consuming megawatts of power. Compare that to the very slow but very many processes running on the human brain which uses maybe 100 watts.

Anyway, this advance which will hopefully someday reduce the power requirements of our machines back a factor of a million or so. If not, we may be relegated to the kind of super machines depicted in science fiction stories like Stanislaw Lem in "imaginary Magnitude". This story which I consider perhaps the most thought provoking one I've ever read is the conversation with a super-intelligent machines with his human tenders about another ULTRA-intelligent machine. (You try writing the dialogue where one of the characters is supposedly vastly more intelligent than any human in history).

Anyway, if this power consumption problem isn't solved, Lem posits that super A.I.s of the distant future will require the power of entire planets with oceans for cooling. The ultimate limit is reached when the machines orbit just at the edges of black holes and use their infinite capacity to absorb heat to perform calculations at the theoretical limit.

Hmm... doesn't make me feel so bad that my iPad is a little warm.

(Hey David, remember to activate the "backdoor" on your system BEFORE you put it online. I want to be able to turn off the killbots by just saying my name!)"

Link to Original Source

Project 1640: A telescope that sees exo-planets directly

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "A telescope has been created that basically very very precisely blocks out the light of a star so that the reflected light of any planets orbiting it can be imaged. As the article states, this is like looking for a firefly next to a searchlight from a thousand miles away. Once the planet's light is isolated it can be examined to see, for example, to see if the air is breathable (has oxygen, an indicator of Life).

Considering that until recently the plan was to spend a few decades and more than a few billion dollars trying to develop and successfully launch the Terrestrial Planet Finder into deep space, I think this is GOOD NEWS.

Here's how it works:
The core of this technical advance is the coordinated operation of: the world's most advanced adaptive optics system, built at Caltech and JPL, which can manipulate light by applying more than 7 million active mirror deformations per second with a precision level better than 1 nanometerâ€"about 100 times smaller than a typical bacterium; a coronagraph, built at the Museum, which optically dims the star but not other celestial objects in the field of view; a spectrograph built by a team from the Museum and Cambridge University that records the images of other solar systems in a rainbow of colors simultaneously; and a specialized wavefront sensor built by a team at JPL that is imbedded in the coronagraph and senses imperfections in the light path at a precision of a nanometer

Anyway, two questions:
1) So when will we know if Pandora exists?
2) Why wasn't this named "Project 1492"?"

Link to Original Source

Wow! Cheap glasses free 3D from LCD panels

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Since I don't pretend to understand how they do it (it uses fast refresh LCDs and powerful GPUs to reproduce holograms?) please follow the link and look at the video released by the MIT news office.

(I tried looking on YouTube for the direct link but I couldn't find it. Sorry!)"

Link to Original Source

Natural Gas is a good way to combat global warming

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Don't let the perfect be the enemy of the good.

Look, I have no ties whatsoever to the natural gas industry (or any other industry, I'm retired!) but this study shows the natural gas is a good way to reduce our use of fossil fuels that produce much higher levels of CO2. We need to buy some time before we can get to a (almost) carbon free future, as I suspected, this study shows natural gas will really help us get there!

For Americans, this gives us the added double bonus of keeping the jobs and money we spend 1) at home and 2) out of the hands of people (terrorists) who want to kill us. (That's the main reason why I don't drive an SUV). Talk about a win-win-win situation.

(Yes there are environmental downsides to fracking but they are not major, largely occur in rural areas, can be largely mitigated. Nothing is free but this is still better than almost all the alternatives except maybe cold fusion.)"

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Cloned Horses ok to compete in Olympics

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Of course they'll still be restricted to the equestrian events (ha ha).

One wonders if they'll be allowed to do the same in say horse or dog racing. It'll then just come down to the ability of the jockeys I guess (or training).

I wonder why they don't make all Olympic athletes use the same exact "equipment" as their competitors. That would get rid of situations like with those super efficient swimsuits that were banned. Of course they really should return to the spirit of the original Games and compete NAKED. That would really improve ratings! (But it would make the winter games rather hazardous.)

When do you think cloning ATHELETES will become legal? That's something I wouldn't put past the old USSR/East European Block. Remember the "women" atheletes they sent?"

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"Time Crystal" could allow computer to outlive universe

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Soooo... Scientists think they can make a crystal that is symmetric not just in space but in time. This evidentially might allow them to make a computer that could outlive the universe.

While I am not sure if my AppleCare warranty could be extended to cover such a long period, I AM sure that I don't understand this at all. I am also sure that there could be some other "interesting" applications with a device where you can interchange the words "space" and "time". Any space-time symmetry experts care to chime in?

Maybe this will allow the "Singularity" optimists to survive the heat death of the universe. (But maybe it won't help against the "Big-Rip")."

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Good news everyone! Eradication close for the guinea worm!

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Here's a horrific disease that's almost been eradicated (down from a few million cases a few decades ago to just FIVE.)

Kudos to the four U.S. presidents, amongst others, who championed this effort and to the Gates foundation for (partially) bankrolling it.

(Don't ask me why my iPad suddenly gets articles from the future. (This one's July 15 2012!). I think I shouldn't have left it near the superconducting magnets at the LHC when the found that Higgs thing)."

Link to Original Source

"Phase change" shirt keeps you cool

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "Ok, I'm not really sure if this fits the exact definition of "phase change", I mean wouldn't it have to change from solid to liquid or something (not entirely bad on some girls I know). Still the basic idea is sound, you cool it off first then when you get hot it absorbs your heat by changing state. Then to reuse it you just cool it off again (thus reverting the state change).

Don't know how much heat it absorbs or for how long or at what rate but these guys are MITers so I figure it might be practical. Also don't know if it's machine washable or the final cost (it's on kickstarter). Sorry! Feeling lazy today (always).

I've always wondered about this kinda technology ever since I heard of a proposal to keep people warm in a house with microwaves; NOT by warming the house and everyone in it but by using the microwaves to heat up JUST the people in it (who are largely water). It would be seemingly much more efficient, no? Well this shirt seems to be just like that, don't cool off an entire building or car but just the person!

Living in Vietnam makes me think a lot about keeping cool as well as keeping my cool! :("

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This is where technology gets scary GOOD

wisebabo wisebabo writes  |  about 2 years ago

wisebabo (638845) writes "I think it was Newton who said that if you knew the position and velocity of every particle in the universe, you could predict the future down to the effect the flutter of a sparrows wing would have on the weather.

Aside from quantum indeterminacy (which of course he knew nothing about) and questions of free will, it is clear we are a long long way from getting even close to the theoretical limits of prediction. Still here's something that, to me, is very impressive.

Some researchers manage to track raindrops (or snowflakes) in front of a light and, IN REAL TIME, change the beam so that they are not illuminated! Voila! Drastically reduced glare! Obvious application for driving cars in inclement weather etc.

I'm hoping that we're entering a new age where computers (and cheap sensors) have become so powerful as to make possible a whole host of "magical" (like Arthur C. Clarke predicted) applications. So life will rapidly get better and better until the Singularity. :) Or Robot Apocalypse. :("

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Kepler data analysis: Earthlike worlds "extremely rare"

wisebabo wisebabo writes  |  more than 2 years ago

wisebabo (638845) writes "Well that sucks.

While this isn't quite what the author of "Rare Earth" said (I think he thought complex life was unlikely, not that the planets themselves were rare), it's still not good.

Anyway, maybe James Cameron was right on basing Pandora on a moon around a gas giant (in this study, plenty of gas giants are in the habitable zone). Here's to our blue-skinned Nav'i overlords!"

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Lower CO2 emissions due to natural gas

wisebabo wisebabo writes  |  more than 2 years ago

wisebabo (638845) writes "Because of the falling prices of natural gas (due to the discovery, and exploitation) of shale gas reserves in the U.S, by fracking) carbon emissions were reduced.

In my book, this is (almost) completely a win-win. Jobs, money, infrastructure and technology are being invested in the U.S., often in communities that need it most (rural poor) rather than going to countries who's people hate our guts. Hopefully our president won't have to "bow down to a Saudi King" and he won't have to apologize for our armed forces burning Korans because we won't be there.

Yes, there is some "minor" (and, as an Californian big earthquake survivor I do mean minor) seismic activity and water supplies may get contaminated but the benefits to the country (and the communities!) outweigh this. (Water, while it should never be wasted, is not particularly scarce in this part of the country, it isnt a desert). And it will help tide us over till we get to a true carbon-neutral economy!

Don't let the perfect be the enemy of the good."

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Not a Troll! Honest question about Climate Change

wisebabo wisebabo writes  |  more than 2 years ago

wisebabo (638845) writes "Ok, I'm a pretty liberal guy who's written on slashdot quite a few times about how the evidence seems to support 1) global warming 2) that's man-made and 3) that it's going to be big enough (more than 2 degrees c) to cause problems.

Then I came across and read (all 58 pages!) this presentation made by a noted skeptic to the British Parliament. He agrees with 1 + 2 but not 3.

It comes down (I think he claims) to one simple fact; doubling of CO2 levels BY ITSELF will only raise temperatures by 1 degree (he says all the models use that), it is the positive feedback from other things in these models (like evaporation) that causes temperatures to soar. He says that these models are wrong on this point and that, in fact, the data shows negative feedback.

After looking a bit around the Internet, including the 4th IPCC report, I couldn't find anything to directly refute this. So realizing that slashdot is the repository of all accessible human knowledge, I was wondering if there was someone out there who could succinctly tell me why he's wrong about the feedback being negative. Or why he's wrong in some other more important way. Or what I got wrong from reading his paper. I'm hoping slashdot will shed some light (not heat, ha ha) on the subject.

Anyway, if I've been wrong all this time about global warming, my apologies! I'll treat my brother (a real skeptic, he bought me that Michael Chrichton book, the one which had the climate guys driving Prius's killing skeptics with darts from poisonous tree frogs!) to a nice dinner.

I still think he's probably wrong; I think most climatologists disagree with him. But science is not a popularity contest, if he's right against most everyone else (like the guy who predicted quasicrystals) I hope he's proven right and wins the Nobel (just like that other guy did)!"

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Forget Sharks with Lasers! How about Flying Squid!

wisebabo wisebabo writes  |  more than 2 years ago

wisebabo (638845) writes "It turns out that it's more energy efficient for squid to FLY through the AIR than swim through water.

So how long until these evolve into flying face huggers? If they're as mean and as big as humboldt squid, we're screwed.

(Maybe on an alien world, where the atmosphere is thicker and maybe gravity less, could these squid evolve into a true jet propelled species? Of course their gills would have to evolve to lungs but that's been done)."

Link to Original Source

The True End of History (and everything else)?

wisebabo wisebabo writes  |  more than 2 years ago

wisebabo (638845) writes "So they're going to release FULL details of how to make this? Time to whip up my bio-reactor!

Ok, so this easily transmissible human to human virus (as predicted by ferret models) *only* has a lethality of 50% but that should be enough to collapse civilization. At least it'll help cut down on global warming.

Still that doesn't compare with that (smallpox?) variant which had an almost 100% fatality rate. I remember that one was suppressed pretty fast. I guess they think this one isn't nearly as dangerous which i would agree with except for the fact that it is AIRBORNE TRANSMISSIBLE (it's based on the Flu!). Boy is sneezing going to be a real conversation killer!

Seems like we've solved the Fermi Paradox; once a species has figured out to make or modify self-replicating nano bots (like viruses), they'll inevitably make one that will in one way or another wipe them out.

Hey, let's see if we can get them to release this in time for 12/21/12!"

Link to Original Source



wisebabo wisebabo writes  |  more than 11 years ago Saw this article on Seems there's a chance (a very small one to be sure) that Microsoft may be facing a 2.2 Trillion dollar fine. That's right Trillion with a "T".

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