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Comment Use RTGs for ion propulsion then comm. (Score 3, Interesting) 77

NASA's needs Pu to get to Uranus (puns intended). If they can manage to get the correct isotope of Plutonium then a space probe that uses ion propulsion would have the necessary electrical power to drive the extremely efficient drive even when, as in this case, it is very far from the sun. Since the space probe DAWN has proven that multi-year thrusting of ion engines does work quite well, this would enable a "flagship" (read "big") mission to get to the very outer planets in less than a decade. It could spend roughly half its time accelerating to a high cruising speed then almost as long decelerating to be captured into orbit.

Then, once the mothership has arrived in orbit then, like Cassini, smaller spacecraft could be employed to explore the various moons and atmosphere of these gas giants. (Unfortunately since the moons of Uranus and Neptune may not be large enough to effectively permit gravity assists like Cassini uses with Titan or Galileo used with the four large Galilean moons, you might need smaller probes because the ion drive may have too low a thrust for dynamic orbital changes). Now the RTGs, having powered the spacecraft to the far reaches of the solar system, could be "gainfully" (ha ha) employed to power a high bandwidth radio transmitter/laser communicator. This would enable the small probes exploring the system to send lots of data back to earth without each carrying a huge antenna, only the mothership.

Why all spacecraft don't utilize the extremely high energy/weight RTGs for deep space PROPULSION is beyond me. I (maybe mistakenly?) think that the RTGs, since it generates its power from the natural decay of a radioactive element, is constantly "on" and if you don't use the power being generated YOU LOSE IT (anyone please correct me if I'm wrong!). So it would seem to be ideal for a space probe that needs to go somewhere far far away from the sun and for which a low thrust high impulse drive (like ion propulsion) that requires large amounts of electric power is ideal. Maybe it's because the DAWN probe needed to prove the ion technology before NASA could commit a flagship mission to it.

Too bad that the isotope of Pu that they need for the probe isn't the same that is used in nuclear bombs, that would be the most apt fulfillment of the biblical(?) phrase "beating swords into plowshares". Oh well, Congress needs to fund the reactor that is used in the nuclear fuel cycle that manufactures this critical resource for space travel.

Of course this is only a stopgap until we get either the Lockheed Martin or MIT (mini) fusion reactors working!

Comment Please explain, how is court ignored? (Score 2, Interesting) 205

This is an honest question (I'm not Indian). How does the government get to override the recently passed decision by the Indian Supreme Court NOT to ban these very same sites? Is there some sort of executive order that allows the government to do so? Or is the government doing something "illegal" (I think the decisions by the Supreme Court must be the very definition of legality right?).

Comment End of Mankind? (Score 2) 312

I didn't realize that "race" could now be determined by a genetic sequence (or two). If true this may lead to some very troubling possibilities.

It would be possible using CRISPR (a recently developed means of precisely targeting an exact genetic sequence) to have a virus that could infect just one particular population. Smallpox comes to mind because 1) very few people in the world are currently vaccinated against it (it was made extinct a while ago) and 2) its DNA has been sequenced and published online. So, using a DNA synthesis machine you could make a version of this virus that would target a particular population.

I believe such machines can now make DNA sequences long enough to create viruses. I also remember someone creating a much more lethal version of smallpox that could kill all of the laboratory animals it infected, including ones vaccinated against "normal" smallpox (I think it was 100% lethal).

Of course, making a virus that would go after a particular Sex as opposed to a racial characteristic should be much easier (just target any gene found on one of the sex chromosomes and not the other.) This particular scenario was explored in Frank Herbert's book "The White Plague". A related scenario might be the film "Children of Men" where all the women(?) are made sterile.

Comment The Real Question Is... (Score 3, Insightful) 160

Will they find extra-terrestrial life IN the solar system or Outside it?

Frankly if they find it within the solar system then it would be a more significant find unless, of course, they found evidence of advanced (intelligent) life outside the solar system. It would mean that the universe is absolutely crawling with life; even if the life was somehow related to that on earth (distributed by asteroid impacts?) that would mean that panspermia is a viable method of distributing life over (at least) interplanetary distances.

In addition, it would mean that there would be a chance of someone going and really examining it within what's left of my lifetime!

So let's hope that it's on Mars (doubtful), Europa/Enceladus (possibly) or Titan. Of course if they find life on Titan, it'll have to be so radically different that our own that it'll blow the minds of just about every biologist in the world! Of course they'd be very very happy to find just fossils.

Comment Politicians will be stupid but scientists/technolo (Score 5, Insightful) 356

Whenever I hear about all the stupid comments and grandstanding from politicians trying to pander to a scientifically illiterate (American) public I despair. However when I look at the (long predicted and now achieved) strides in solar power, a see a "ray" of hope.

Finally solar power is becoming cost competitive even with coal. Hopefully in a few more years and certainly less than a decade it will be decisively so. At that point, one hopes, renewable power will no longer be a political decision but a purely economic one.

This, of course, won't solve global warming, certainly not "over night" (ha ha). The vast build up of CO2, thermal lag and feedback loops (permafrost melting) means we will be dealing with this for generations to come. But it might slow down the buildup enough so that new carbon sequestration technologies created (again by scientists and technologists) can fix the problem for good.

Comment Are people being killed because of Snowden? (Score 0, Troll) 228

When Snowden released documents that indicated that (amongst other things) Huawei had been compromised, I wondered if human intelligence or "social engineering" may have been used to obtain some passwords. If so, and if the Chinese govt. found out who (perhaps inadvertently) gave them away, that person would at the very least seen their employment terminated and perhaps even been terminated themselves!

Now with the frank admission that there are human spies at work in China for the NSA, I'm sure the Chinese govt. has redoubled their efforts to find (and kill) them. If so, then these leaks may be directly responsible for the deaths (probably after considerable torture) of individuals who, for whatever reason, were helping the U.S.

So, this is a very serious consequence of the leaks. Do you still agree that Snowden was justified in leaking all of this presumably without giving the U.S. advance warning of what he was going to release (so that they could get vulnerable individuals to safety?).

Comment Partial answer to Fermi's paradox? (Score 1) 80

From the abstract: "life as it exists on Earth could not take place at z>0.5". I take this to mean (since I'm not a professional astronomer I am guessing that the variable "z" represents redshift) that life couldn't get started in the earl(ier) universe because the galaxies were closer together/with more gamma ray bursters etc.

So a partial answer to Fermi's paradox (where are they?) is that we are one of the "first" to evolve into sentient beings because for "most" of the period before life evolved on the earth the whole universe was mostly uninhabitable. Of course I put "first" and "most" in quotation marks because we're talking about billions of years here; maybe the universe became reasonably habitable "only" a billion years before life arose on planet earth; that's still a lot of time! That's why I say this might be a "Partial" answer to Fermi's paradox, there would still be time for some civilizations to arise way before us. Just not as many and perhaps no really ancient multi-billion year old civilizations.

Comment Don't buy/invest in mainland China (if you can) (Score 5, Insightful) 191

I know that this is a hard choice (especially since I heard Alibaba has soared by 38% in its first day) but please consider the following:

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 the Chinese GOVERNMENT 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 government doesn'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 the Chinese government 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 the Chinese government, not the U.S. government 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).

(If you're wondering why I'm advocating not buying/investing in China and hurting Chinese citizens as opposed to just their government, remember that the world boycotted South Africa during their Apartheid regime even though it undoubtedly hurt many whites and blacks who were good people. And it worked.)

Comment Do they know the gravity field vectors? (Score 2) 35

I would think that on such a wildly irregular body (the topology has been likened to a rubber duck), not only does the strength of the comet's gravity vary from place to place but the DIRECTION does as well. Something that appears to be "flat" or horizontal may, in fact, be a steeply sloping surface because the gravity vector is not perpendicular to the surface. Of course if it the surface were a liquid or very fluid particles then the surface would always be perpendicular to the local gravity vector but it appears as if it is made of a very heterogenous bunch of materials some of which are rigid (like rocks).

Then again, the surface gravity is likely to be so small (1/100th of a gee? 1/1000th of a gee?) that maybe it doesn't matter. From what I understand the probe has to harpoon itself to the surface; though I don't know whether that is because the gravity is so low that it might just bounce back off into space or because of the outgassing from the comet as it approaches the sun will threaten to "blow it away".

Too bad the comet's orbit doesn't have its closest point closer to the sun, I'd expect some real "fireworks". As it is, I'm not sure how much outgassing they expect.

Comment It's only ahead of Siding Spring by a month (Score 2) 67

Hmm... It's only ahead of the comet Siding Spring by about a month. Will it have time/fuel to "duck and cover" by getting to the far side of the planet before the close approach of the comet and the potential of a cometary dust storm that could wreck it? (Contrary to what some people think, it doesn't take much energy to change your orbital position IF you've got time. A simple change of 1 meter/sec from the thrusters will, after one year mean a distance of over 30,000 km. That simplification ignores some orbital dynamics but you get the picture.) Of course Mangalyaan doesn't have a year but it has much greater delta-vee capability, its orbital insertion burn is (I think) 1.6 KM/sec. And maybe it would've been on the far side of the planet anyway.

On the other hand, maybe it's near the comet NOW, or nearer to the comet than any other spacecraft. Perhaps it can take some good close-ups of the comet or at least see it from a different angle. (If it can see a full or partial eclipse of the sun by the comet, scientists may be able to determine the comet's composition or the composition of the comet's coma. It might be able to do it using radio wave occultation from earth.). In any case, it's good that there will be another spacecraft near the comet when it arrives at mars! Too bad the U.S. isn't willing to risk sacrificing one of its older orbiters (I think one has been around mars for about a decade) for a close flyby. (Again, given enough advance planning, a surprisingly small amount of delta-vee would be required to put one of the orbiters on a collision course, especially if gravitational chaotic resonances AKA "the interplanetary highway" were harnessed.)

Too bad we didn't know about this close encounter say a decade ago. We might have been able to send a probe that could've used mars' gravity to slingshot a probe into a matching trajectory with it so that, like the ESA Rosetta probe, we could rendezvous, orbit and land on it!

Comment Piracy will kill it (but not in the way you think) (Score 1) 93

No, the Chinese government would probably WELCOME piracy of their O.S. because it would mean that their backdoored (it that a word?) O.S. was spreading even beyond what they hoped for.

The problem is that very few software companies like Microsoft would write applications for it knowing that the number of actual PAYING customers in China will be few. I think I read somewhere that a Microsoft exec. said they made more money in the Netherlands than in all of China because of piracy. The simple business analysis would be that they wouldn't be able to recoup their development costs for another platform, especially if it was pirated even more. Maybe if China told every software company that wanted to sell its products in China that they HAD to develop for their O.S. then they would actually get some native applications; I think it would be equally likely that since these software companies weren't getting a lot of revenues anyway (because of piracy), they might pack up and leave. That's not to mention what using the Chinese O.S. would leak (more like gush like a firehose!) to the Chinese industrial complex about their products.

I'm assuming that if the O.S. was "compatible" in the sense that it could run Windows programs using some sort of similar API or emulation that people wouldn't tolerate the poor performance/bugginess. I figure they'd just buy a computer with the Chinese O.S., wipe the drive and install their (pirated) copy of Windows for the best computing experience (if you can call Windows "best"!). Also, as bad as the NSA is, perhaps the average Chinese citizen would prefer some faraway American govt. agency snooping on their computer than the jack-booted thugs who would kick down your door in a moments notice which is basically the Chinese State Security apparatus.

Comment Uh oh, this isn't good (if it works) (Score 2) 162

This is a step along the road towards the Morlocks and Eloi of H. G. Wells "The Time Machine".

While this isn't as bad as "Gattaca" or "Brave New World" with their emphasis on eugenics; it's definitely not good for the concentration of wealth, power and yes, intelligence. When people can be ACCURATELY rated in terms of all their various intellectual abilities (as they already are in Chess ability) it will mean a further stratification of society and concentration of advantages.

While this has always being going on throughout history (and pre-history) if they really apply scientific techniques it could dramatically enhance its predictive power.

Maybe, eventually, humanity will start to diverge into multiple species. :(

Comment Not on human timescales (Score 1) 44

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").

Comment Too bad this didn't happen in 50 years (Score 4, Interesting) 44

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).

The bomb will never go off. I speak as an expert in explosives. -- Admiral William Leahy, U.S. Atomic Bomb Project