Swihc to pendantic mode - it was Mars Climate Orbiter, not Mars Polar Lander. The latter suffered from a more complex (but just as unforgivable) SNAFU.
First, such a crash is vanishingly unlikely if the mission is planned right.
Second, The radiation environment on the surface of Europa is really bad, so the radiation is unlikely to be much additional hazard.
Toxins in the reactor could be a concern, although it is not generally posited that anything is living on the surface, but rather under a thin crust of ice.
Most signals would be very hard to detect with our state of the art G/Ts, but not all. Signals sent with high gain by ETIs could include interplanetary or interstellar communications (not intended for us), radar signals (we do this to study asteroids), or microwave propulsion systems.
it seems as if we the ol' confusions but sufficient and necessary conditions:
1. A given, although "Sending" might not be the best verb. IT need not be "Sent" to us, we might just be picking it up by shear luck.
2. See my comment on 1. There's no need to assume this at all.
3. Yes, well this would take just a little knowledge to conclude, although a different technological path might make it more difficult. Still, it;s highly likely that this pectrum ouwld get some use, even if not to prosecute a SETI program (see 1 and 2 above).
4. I'ts not an instantaneous event, but a window that gets wider every day. Keeping SETI seraches going and improving their sensitivity keeps forcing the window higher and wider.
5. Or, "they" do not have any particular (unanimous) reason to want to hide their presence over the duration of the window, whether they think like us or not. Put that way, it seems more likely.
6. No one here "just sit listening." It takes a lot of work and deep knowledge of radio astronomy. And how did you make the shift from transmitting to "just sit listening?" Why is that a necessary condition?
Please, no more lame references to the MCO loss! this was NOT because people didn't know that Newtons and Pounds aren't the same thing, but because two different organizations use the different units, and the software interface between them didn't do the conversion.
That's it exactly. The amount of delta-velocity we're talking about here is thousands of meters per second, sothe mass fraction of the fuel would be >> 50%. Also, the ISS isn't very maneuverable, so anything that wants to rendezvous with it needs a pretty good terminal guidance system, which is expensive. Stardust is a Discovery mission, so doesn't have or need those kinds of big ticket items.
Very likely, the American astronmers used units of kilometers originally. In mybrief forays into the astronomical literature, I've found A.U.s and kilometers and MKS units, but no miles, feet or pounds.
Well, I get that it's about 279 Joules/kg to move water with perfect efficiency from 2003 VS2 to Mars orbit, but that thing has a mass of about 10^18 kg or more. Maybe more like 10^19. So we're talking about 10^21 Joules. So, I don't see how you'd do it. Am I missing something?
A summary of what's known about Plutino statistics reveals that they're all pretty eccentric (good) and some are reasonably close to the ecliptic (good), but they cluster longitudinally well away from Neptune, which makes a Neptune GA tough to pull off in a reasonable time. That was my main hope for getting there. So, you'd have to fly by one, and hope that you get lucky with another - probably not a Plutino per se at 40 A.U. mean solar distance, but a KBO is certainly possible.
I think Apple would say that if that's the sort of thing you're inclined to do, then the iMac is not for you. It;s for people who aren't too curious about what's under that dome thinggy. OTOH, there is someone who will muck about and hack just about anything.
You don't have to cover the whole arc. It depends on the population of objects in that orbit. I would think encounters a few years apart would be at least plausible, with cheap periods of hibernation between. The trick would be to have fallback modes that did respectable science with less and less power as the RTG fades. Enabling technologies like very low power imagers/spectrometers and large, lightweight deployable antennas are not outside the realm of feasibility.
I think we should study a grand tour of the Neptune 2:3 resonance orbit. Perhaps we could fly by several of these objects. Might make an interesting senior thesis for a suitably ambitious young person...
Ok, I'll say it: ISS's orital inclination can't be changed enoug to do any good. Also, the waystation idea is far from a proven winner unless you've got materials flowing both directions.
No, cost is essential. If it costs less to deliver a larger load where only 80% of the original payload makes it, then we'll send hydrogen tanks that loose 20% of their hydrogen. Using a high speed chemical rocket is tremendously expensive.
Have enough of these en route...
Huh? There's the small matter of velocity matching.
more like 0%. The boiloff would get you in a matter of days, nit months.
Given the enormous bureacratic and political difficulty of launching a samll nuclear reactor to the outer solar system, what kind of flack do you think we'd get if we steered a comet in to the moon?
Then you have to capture the comet's volatiles before they boil off. you'd have about 14 days if you were lucky, but they'd be scattered over a wide area. Seems pretty unlikely to me.
Thinking out loud, it seems to me an efficient way to get Hydrogen to the moon would be to send Methane or Propane. You need the carbon for horticulture, anyway. There's plenty of oxygen in lunar soil.
How and why? ISS is in the wrong orbit for efficient lunar transfers, and is in no way designed as lunar waystation. It can barely function asw a microgravity lab.
Efficient and cheap propulsion technologies such as Ion propulsion could be used to keep a constant supply of hydrogen "on the way".
? Ion engines do have a high specific impulse, but also have very low thrust and require lots of power. Even a small spacecraft like SMART-1 is taking months to get to lunar orbit on an ion engine, and you've got this little bitty spacecraft with big solar arrays. It's not at all clear that this is the way to go - to get efficient H storage, you'd have to havea cryo container, and that's going to mean some finite leakage rate, and that means short trip times are essential.
Basically, if there's no source of Hydrogen on the moon (water or Methane), then no lunar bases for a long time. The Space Elevator could change that if we could make it realistic.
Last I checked, the market cap for SUNW was about 13 billion. Way down from where it used to be, but still a lot compared to Apple's 8 billion. That's a lot for Apple to swallow - they'd have effectively to go into debt.
Sun is struggling to keep their high-end niche while getting pushed out of the low end - it's not clear to me that they have a brilliant future, or that Apple could help much (there's that "synergy" thing again). Sun's products are great (we use them extensively), but everyone is gunning for their markets with cheaper stuff.
The precedents aren't very good. I don't see that Compaq got their money's worth for DEC, or that HP got it's money's worth for Compaq, or that GM got anything like a good investment in Hughes Aircraft. The list goes on.
9.5 Million is durn cheap for a space mission. Big commmunications satellites, for example, run about $200 millions to build and launch. A cheap NASA-managed mission runs around 50 million$ or more - although SpaceDev recently did one for much cheaper based on the PI model (minimal NASA involvement), in which UC Berkeley managed the mission.
The moon's shadow is always somewhere, just not always on the Earth's surface. If you have an advanced spacecraft, it ought to be easy to observe a total eclipse of any convenient star any time you want.
I've had about 2 e-mails a day of this ilk with respect to my Earthlink account for at least 3 months. A similar scam is in work with respect to Paypal. You don't need to be a total dunce to fall for this, either. Just naive and not savvy with raw e-mail source.
I think it is true that the people we are now are not emotionally well equipped to live very long lives. However, the rhythms of life now are very diferent from what they were for our shorter-lived ancestors, and somehow we adapt.
Is there any evidence that healthy older people are in any way mentally impaired? Sure, some suffer from senile dementia or Alzheimer's, but many don't. Frank Lloyd Wright did much of his more famous work after turning 70, for example.
Presumably living longer would mean aging much more slowly, so a 100 yaeer old brain wold be more like a 20 year old brain is now - still damaged from undergraduate partying, but making headway.
I doubt anyone will embark on a 500 year life span in the next 100 years, but even if it were 200 years, then you would certainly alter life patterns. You'd want to retire, re-educate, and embark on new careers, but a lot of the accumulated knowledge would carry over. You'd get people entering medical school after long careers in say, finance, or becoming scuba instructors and moving to Florida after 90 year farming in Minnesota.
As for the increased skepticism, I'm all for it. And I don't think the pace of progress would be seriously impaired - remember it would take the better part of 500 years before you had anyone 500 years old.
And I should follow up to say that duplication of this negative result would not be silly, either. However, the burden of proof is on those who claim therapeutic value.
But you make no coherent argument that the study is silly. You see, it wasn't about theology, but therapy. The rescuers have already abandoned all attempt at saving the God of the Gaps.
Falsifying hypotheses is an important scientific activity. For example, if a drug company put out a new drug that they claimed cured cancer, would it not be important to test it? And would not a negative result be an important one? There HAVE been recent claims for the therapeutic efficacy of prayer, but the studies have suffered problems with sample size and methodology (and even fraud). Someone at Duke said: "let's make a stab at doing this right." Now the therapeutic claims are very much in doubt, and we don't have to call in a parson in order to provide good care.
No therapeutic methods should be based on a single study. There are always variables that weren't explored. Had there been a positive result, it would have demanded duplication and review.
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Swihc to pendantic mode - it was Mars Climate Orbiter, not Mars Polar Lander. The latter suffered from a more complex (but just as unforgivable) SNAFU.
First, such a crash is vanishingly unlikely if the mission is planned right.
Second, The radiation environment on the surface of Europa is really bad, so the radiation is unlikely to be much additional hazard.
Toxins in the reactor could be a concern, although it is not generally posited that anything is living on the surface, but rather under a thin crust of ice.
Most signals would be very hard to detect with our state of the art G/Ts, but not all. Signals sent with high gain by ETIs could include interplanetary or interstellar communications (not intended for us), radar signals (we do this to study asteroids), or microwave propulsion systems.
"Collosal?" If only!
it seems as if we the ol' confusions but sufficient and necessary conditions:
1. A given, although "Sending" might not be the best verb. IT need not be "Sent" to us, we might just be picking it up by shear luck.
2. See my comment on 1. There's no need to assume this at all.
3. Yes, well this would take just a little knowledge to conclude, although a different technological path might make it more difficult. Still, it;s highly likely that this pectrum ouwld get some use, even if not to prosecute a SETI program (see 1 and 2 above).
4. I'ts not an instantaneous event, but a window that gets wider every day. Keeping SETI seraches going and improving their sensitivity keeps forcing the window higher and wider.
5. Or, "they" do not have any particular (unanimous) reason to want to hide their presence over the duration of the window, whether they think like us or not. Put that way, it seems more likely.
6. No one here "just sit listening." It takes a lot of work and deep knowledge of radio astronomy. And how did you make the shift from transmitting to "just sit listening?" Why is that a necessary condition?
Please, no more lame references to the MCO loss! this was NOT because people didn't know that Newtons and Pounds aren't the same thing, but because two different organizations use the different units, and the software interface between them didn't do the conversion.
That's it exactly. The amount of delta-velocity we're talking about here is thousands of meters per second, sothe mass fraction of the fuel would be >> 50%. Also, the ISS isn't very maneuverable, so anything that wants to rendezvous with it needs a pretty good terminal guidance system, which is expensive. Stardust is a Discovery mission, so doesn't have or need those kinds of big ticket items.
Very likely, the American astronmers used units of kilometers originally. In mybrief forays into the astronomical literature, I've found A.U.s and kilometers and MKS units, but no miles, feet or pounds.
Well, I get that it's about 279 Joules/kg to move water with perfect efficiency from 2003 VS2 to Mars orbit, but that thing has a mass of about 10^18 kg or more. Maybe more like 10^19. So we're talking about 10^21 Joules. So, I don't see how you'd do it. Am I missing something?
2003 VS 2 has an inclination of 14.8 degrees, BTW
A summary of what's known about Plutino statistics reveals that they're all pretty eccentric (good) and some are reasonably close to the ecliptic (good), but they cluster longitudinally well away from Neptune, which makes a Neptune GA tough to pull off in a reasonable time. That was my main hope for getting there. So, you'd have to fly by one, and hope that you get lucky with another - probably not a Plutino per se at 40 A.U. mean solar distance, but a KBO is certainly possible.
I think Apple would say that if that's the sort of thing you're inclined to do, then the iMac is not for you. It;s for people who aren't too curious about what's under that dome thinggy. OTOH, there is someone who will muck about and hack just about anything.
You're not going to be taken seriously if you begin your posts with insults.
You don't have to cover the whole arc. It depends on the population of objects in that orbit. I would think encounters a few years apart would be at least plausible, with cheap periods of hibernation between. The trick would be to have fallback modes that did respectable science with less and less power as the RTG fades. Enabling technologies like very low power imagers/spectrometers and large, lightweight deployable antennas are not outside the realm of feasibility.
I think we should study a grand tour of the Neptune 2:3 resonance orbit. Perhaps we could fly by several of these objects. Might make an interesting senior thesis for a suitably ambitious young person...
Ok, I'll say it: ISS's orital inclination can't be changed enoug to do any good. Also, the waystation idea is far from a proven winner unless you've got materials flowing both directions.
Huh? There's the small matter of velocity matching.
more like 0%. The boiloff would get you in a matter of days, nit months.
Given the enormous bureacratic and political difficulty of launching a samll nuclear reactor to the outer solar system, what kind of flack do you think we'd get if we steered a comet in to the moon?
Then you have to capture the comet's volatiles before they boil off. you'd have about 14 days if you were lucky, but they'd be scattered over a wide area. Seems pretty unlikely to me.
Thinking out loud, it seems to me an efficient way to get Hydrogen to the moon would be to send Methane or Propane. You need the carbon for horticulture, anyway. There's plenty of oxygen in lunar soil.
How and why? ISS is in the wrong orbit for efficient lunar transfers, and is in no way designed as lunar waystation. It can barely function asw a microgravity lab.
? Ion engines do have a high specific impulse, but also have very low thrust and require lots of power. Even a small spacecraft like SMART-1 is taking months to get to lunar orbit on an ion engine, and you've got this little bitty spacecraft with big solar arrays. It's not at all clear that this is the way to go - to get efficient H storage, you'd have to havea cryo container, and that's going to mean some finite leakage rate, and that means short trip times are essential.
Basically, if there's no source of Hydrogen on the moon (water or Methane), then no lunar bases for a long time. The Space Elevator could change that if we could make it realistic.
i don;t think Apple will buy Sun.
Last I checked, the market cap for SUNW was about 13 billion. Way down from where it used to be, but still a lot compared to Apple's 8 billion. That's a lot for Apple to swallow - they'd have effectively to go into debt.
Sun is struggling to keep their high-end niche while getting pushed out of the low end - it's not clear to me that they have a brilliant future, or that Apple could help much (there's that "synergy" thing again). Sun's products are great (we use them extensively), but everyone is gunning for their markets with cheaper stuff.
The precedents aren't very good. I don't see that Compaq got their money's worth for DEC, or that HP got it's money's worth for Compaq, or that GM got anything like a good investment in Hughes Aircraft. The list goes on.
9.5 Million is durn cheap for a space mission. Big commmunications satellites, for example, run about $200 millions to build and launch. A cheap NASA-managed mission runs around 50 million$ or more - although SpaceDev recently did one for much cheaper based on the PI model (minimal NASA involvement), in which UC Berkeley managed the mission.
The moon's shadow is always somewhere, just not always on the Earth's surface. If you have an advanced spacecraft, it ought to be easy to observe a total eclipse of any convenient star any time you want.
I've had about 2 e-mails a day of this ilk with respect to my Earthlink account for at least 3 months. A similar scam is in work with respect to Paypal. You don't need to be a total dunce to fall for this, either. Just naive and not savvy with raw e-mail source.
I think it is true that the people we are now are not emotionally well equipped to live very long lives. However, the rhythms of life now are very diferent from what they were for our shorter-lived ancestors, and somehow we adapt.
Is there any evidence that healthy older people are in any way mentally impaired? Sure, some suffer from senile dementia or Alzheimer's, but many don't. Frank Lloyd Wright did much of his more famous work after turning 70, for example.
Presumably living longer would mean aging much more slowly, so a 100 yaeer old brain wold be more like a 20 year old brain is now - still damaged from undergraduate partying, but making headway.
I doubt anyone will embark on a 500 year life span in the next 100 years, but even if it were 200 years, then you would certainly alter life patterns. You'd want to retire, re-educate, and embark on new careers, but a lot of the accumulated knowledge would carry over. You'd get people entering medical school after long careers in say, finance, or becoming scuba instructors and moving to Florida after 90 year farming in Minnesota.
As for the increased skepticism, I'm all for it. And I don't think the pace of progress would be seriously impaired - remember it would take the better part of 500 years before you had anyone 500 years old.
On the scale of evil, "insidious" is at least +2 points. Besides, state's attorneys general are getting exercised over this, so it's not a triviality.
And I should follow up to say that duplication of this negative result would not be silly, either. However, the burden of proof is on those who claim therapeutic value.
But you make no coherent argument that the study is silly. You see, it wasn't about theology, but therapy. The rescuers have already abandoned all attempt at saving the God of the Gaps.
Falsifying hypotheses is an important scientific activity. For example, if a drug company put out a new drug that they claimed cured cancer, would it not be important to test it? And would not a negative result be an important one? There HAVE been recent claims for the therapeutic efficacy of prayer, but the studies have suffered problems with sample size and methodology (and even fraud). Someone at Duke said: "let's make a stab at doing this right." Now the therapeutic claims are very much in doubt, and we don't have to call in a parson in order to provide good care.
No therapeutic methods should be based on a single study. There are always variables that weren't explored. Had there been a positive result, it would have demanded duplication and review.
Ah, the seductive power of intractable mystery!