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Post by blademaster2 on Sept 30, 2022 17:41:22 GMT -5
Hey Cyn1, in case I was not clear I am on your side on this.
I am less impressed than many people with him, and I think his public image (to some) as a 'technology genius' is rather naïve.
He's got *something* going on that is positive, and it might pave the way for improved infrastructure to support these type of vehicles so we will be ready once that new "unobtainium-based battery" emerges on the market.
Until then I think we are yet to see the tidal wave of complaints as folks see how the full life-cycle cost of batteries is higher than they expected, and (hope I am wrong) there is an inferno with all of the batteries unleashing their stored energy all at once after a collision.
Now back to the DART Mission. Diverting anything that big or bigger in space is risky. It is possible that it would otherwise have missed the Earth, but now after this it might be on a collision course. We cannot predict far enough out in time to know for sure. I'd hate to think that my eventual great-grandkids are now doomed because of this. Still, if we *can* divert a known threat sometime in the future so that it misses us it would save the planet and justify all of the money ever spent on space technology. That is a noble quest.
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Post by reTrEaD on Sept 30, 2022 23:03:21 GMT -5
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Post by reTrEaD on Sept 30, 2022 23:49:35 GMT -5
Now back to the DART Mission. Diverting anything that big or bigger in space is risky. It is possible that it would otherwise have missed the Earth, but now after this it might be on a collision course. We cannot predict far enough out in time to know for sure. That's really not a danger. One of the reasons this asteroid pair was chosen is because we were able to affect the time the smaller asteroid (Dimorphos) orbits the larger one (Didymous) enough to measure the change without appreciably affecting the path of the pair. The mass and velocity of the spacecraft was small enough in relationship to the mass of Dimorphos that it was essentially a tiny nudge. However, it was large enough that they expect to see several minutes shaved off the 11.9 hours it takes for Dimorphos to orbit Didymous. I think this was basically a proof of concept mission. And they should be able to determine how close their estimates of the redirection was, to the actual results. I reckon it will take a much more massive spacecraft with a much higher velocity at impact to change the path of an asteroid on a collision course with Earth. And they'll need to encounter that asteroid at a very long distance from Earth so the tiny change in angle of its path results in a safe distance of its encounter with Earth.
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Post by cynical1 on Oct 1, 2022 5:57:50 GMT -5
Hey Cyn1, in case I was not clear I am on your side on this. No, I caught it. I was merely expounding on your theme. NASA's Mission Statement reads, in part, " The DART mission is NASA's demonstration of kinetic impactor technology, impacting an asteroid to adjust its speed and path. DART will be the first-ever space mission to demonstrate asteroid deflection by kinetic impactor." To me, this is telling...especially the use of the word "demonstration". By definition, this means: "give a practical exhibition and explanation of". The fact that, by their admission, this is "the first-ever space mission to demonstrate asteroid deflection by kinetic impactor", leaves the outcome open to examination, as we've never done this before and have no real idea WTF may happen over time. In 1936 Robert K. Merton wrote an article article titled "The Unanticipated Consequences of Purposive Social Action". He defines unintended consequences as "unanticipated consequences or unforeseen consequences are outcomes that are not the outcomes intended by a purposeful action". Granted, our discussion has been about a technical action, but in the article Merton identified five sources of unanticipated consequences. 1.) Ignorance 2.) Error 3.) Imperious immediacy of interest 4.) Basic values 5.) Self-defeating prediction It looks like this: I'll take it a step farther. What if, by hitting Dimorphos, we don't drive anything into our solar system, but into another populated system we are unaware of. Won't that be fun meeting our new neighbor's once they find out who crashed an asteroid into their sun... HTC1
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Post by newey on Oct 1, 2022 6:57:00 GMT -5
I'll take it a step farther. What if, by hitting Dimorphos, we don't drive anything into our solar system, but into another populated system we are unaware of. Won't that be fun meeting our new neighbor's once they find out who crashed an asteroid into their sun An asteroid falling into a star would do nothing but add a bit of mass to the star. And, at any velocity we could add to the asteroid so deflected, the Earth would be a dead cinder by the time it reached any other system. Further, if anyone is really worried about this, we could presumably plan the deflection to go out of the galactic plane where the odds of it entering another system would be even more miniscule. One can always postulate some hypothetical situation whereby some unwanted event might occur. Maybe all our calculations of solar lifespan are off, and the Sun flames out at midnight tonight . . . Yes, there are unknowns when we talk about deflecting an asteroid. But the danger of an asteroid striking Earth is not unknown, it has happened in the past and, given the number of near-Earth objects (NEOs), it will happen again. Some folks have calculated that we may well be "overdue" for such a collision, with obviously catastrophic results for us poor humans. The cockroaches will probably survive . . . I note that, earlier, the idea of nuking a potential impactor asteroid was touted as a plan, as per the movie. But that option has been largely ruled out, by NASA and other researchers, because of the danger of unintended consequences- you might end up with several large-ish chunks hitting the Earth. Redirection looks like our "best bet" at this point. I, for one, am glad that NASA has taken the trouble to try this mission. Yes, it is a demonstration, a proof of concept. But the data we collect will tell us, hopefully, whether this approach is viable or whether we have to go back to the drawing board. Human civilization certainly has its issues, but I think it's worth saving for our grandchildren if we can do so.
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Post by thetragichero on Oct 1, 2022 10:45:56 GMT -5
Mass transit, when done correctly, provides low cost transportation, employment within the operator and an incubator for smaller businesses that benefit from the daily passage of commuters. having spent my formative adult years (18-22) living right across the river from "the city" i was able to experience firsthand what efficient public transportation could do (move large numbers of people for very cheap. even today $2.75 can get you just about anywhere you want quickly) it's always amazed me later in life that very few places are willing view these as viable options. even yesterday i was able to travel ~180 miles for about what it would've cost in gas and tolls (and in a comparable amount of time) while fartin' around on my laptop The cockroaches will probably survive . . . 70s/80s peavey amps too
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Post by newey on Oct 1, 2022 10:59:20 GMT -5
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Post by reTrEaD on Oct 1, 2022 19:31:54 GMT -5
Mass transit, when done correctly, provides low cost transportation, employment within the operator and an incubator for smaller businesses that benefit from the daily passage of commuters. having spent my formative adult years (18-22) living right across the river from "the city" i was able to experience firsthand what efficient public transportation could do (move large numbers of people for very cheap. even today $2.75 can get you just about anywhere you want quickly) it's always amazed me later in life that very few places are willing view these as viable options. even yesterday i was able to travel ~180 miles for about what it would've cost in gas and tolls (and in a comparable amount of time) while fartin' around on my laptop cynical1 's use of the term incubator, triggered one of many unpleasant memories of using mass transit. There was a guy across the aisle from me who looked like death warmed over. And he was coughing incessantly. I contemplated looking for a seat further away from him. Then he sneezed. He wiped the snot running down his nose with his hand and proceeded to wipe his hand on the seat next to him. I ran to another seat. Aside from occasional unpleasant interactions with other riders, mass transit isn't horrible but it does present some challenges. If you live some distance away from the transit line, there are often park and ride lots available. But your destination still needs to be reasonably close to the transit line, else you'll be walking a considerable distance. Using mass transit also limits your ability to adapt your schedule. If you ride to work, then find you need to go somewhere after work that isn't close to the transit line, you end up riding home, then getting into your car to drive to the somewhere. Occasionally that somewhere is in the same direction as work, but further away. Not exactly the most efficient use of time.
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Post by stevewf on Oct 1, 2022 20:36:58 GMT -5
That is pretty good. Cockroaches and Peavy amps. And now I know that 70s/80s Peavys have a reputation for being tough. But really I wonder if (hope that) roaches can be trained to play guitar.
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Post by thetragichero on Oct 1, 2022 23:11:23 GMT -5
if you throw a 70s peavey head down the stairs, the only thing likely to break is a stair. love em. amps for workin` folk
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Post by sumgai on Oct 2, 2022 13:44:14 GMT -5
if you throw a 70s peavey head down the stairs, the only thing likely to break is a stair. love em. amps for workin` folk True story. When I was in business, a local band had a roadie bring in a Peavey Classic 50 for "something's buzzing inside". (The guitarist and bassist both knew me.) I almost didn't have to ask, but I did anyway. Curiosity, you know. "What happened to this poor guy?" "One of my crew smoked a bit too much weed, and both him and the amp took a header down the steps leading to the exit door." Knowing the band, and knowing that they had only one roadie, I kept my mouth shut. Didn't see much profit in saying anything, positive or negative. Turned out to be one of the power tubes went South. Par for the course. $65 bucks later, he's out the door and hopefully, a little wiser about self-mobilization while carrying heavy things during times of "medicinal use" of non-prescription pain control substances. Moral of the story: I agree wholeheartedly that Peavey is probably the best overall choice for those players who aren't "Name-Brand Snobs". Hartley knew what he was doing, and he did it well. (And is still doing it well, in fact.) sumgai
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