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"Scientific" Dreams Of Travel To Stars Shattered: Mysterious Force Pulls Back NASA Probe In Deep Space
Stephen Knight wrote:
Interesting. Your god apparently likes to mess with space probes more than stopping the slaughter of six million Jews, feeding starving babies or stopping violent crime. Well, since these space probes are apparently being stopped by an invisible hand, either it's God, or we'll have to blame Adam Smith for it! John Savard |
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"Scientific" Dreams Of Travel To Stars Shattered: Mysterious Force Pulls Back NASA Probe In Deep Space
Sound of Trumpet quoted:
The team says no current theories explain why the force stays constant: all the most plausible forces, from gravity to the effect of solar radiation, decrease rapidly with distance. It's certainly true that the force of the Sun's gravity on these space probes would diminish at the rate of 1/(r^2); however, the gravitational force of the Oort cloud only begins to diminish at that rate _once one is no longer *inside* the Oort cloud_. Hence, eliminating gravity seems to be premature. Also, how was it determined that the motions of these space probes had been disturbed? Was it solely by radar echoes and time delays of signals to and from the probes? I suspect that is likely; such a small deviation, barely detectable by those means, would not be detectable by triangulation. So, it's possible that the speed of light in a _true_ vacuum, as found in distant space, is just faster than the speed of light in the vacuums we can make and measure light in upon Earth! I'll admit that's unlikely, but the results don't really eliminate that alternate possibility either. John Savard |
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"Scientific" Dreams Of Travel To Stars Shattered: Mysterious Force Pulls Back NASA Probe In Deep Space
Joe Strout wrote:
How can you read about an acceleration of 6 mph per century, and not see that this would be absolutely no impediment to interstellar travel? Well, if one is looking for something to beat the infidels over the head with, one might not read carefully. However, let's not get *too* hasty here. A space probe travelling at 6 mph would take more than a century to reach Alpha Centauri. Therefore, this force clearly would be an impediment to interstellar travel by space probes on ballistic trajectories travelling at slow speeds. Light travels at 186,000 miles per second. So Alpha Centauri is about 25,000,000,000,000 miles away. Let's imagine a space probe which begins from a standing start at the position of our solar system, undergoing an acceleration of 6 mph per century. To get the units right, that will be 5,256,000 miles per century squared. So, at the end of one century, it will have covered 2,628,000 miles, according to the formula (1/2)a(t^2). Such a space probe will have been travelling for 3,084 centuries before reaching Alpha Centauri. Thus, when it reaches Alpha Centauri, it will be travelling at about 18,000 miles per hour - therefore, reaching the stars with a space probe accelerated to that velocity (say by "gravitational propulsion" - an encounter with Jupiter) is indeed prevented by such a force. However, 18,000 miles per hour _is_ rather slow even by current standards of space travel, so it _is_ true that this force doesn't prevent interstellar travel. John Savard |
#25
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"Scientific" Dreams Of Travel To Stars Shattered: MysteriousForce Pulls Back NASA Probe In Deep Space
On Thu, 05 Oct 2006 15:37:43 -0700, Sound of Trumpet wrote:
he speed of the two probes is being changed by about 6 mph per century - a barely-perceptible effect about 10 billion times weaker than gravity. And how does that "shatter" dreams of interstellar travel? An old Ford Pinto firing on one cylinder has enough energy to over come a force *that weak... -- Mark K. Bilbo -------------------------------------------------- "As hip as it is for outsiders to blame New Orleans for everything bad that happened during and after Hurricane Katrina, the truth is that the people who lived here were much more prepared for a big storm than the federal government that promised us flood protection." [Jarvis DeBerry] http://makeashorterlink.com/?V180525DC "Everything New Orleans" http://www.nola.com |
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"Scientific" Dreams Of Travel To Stars Shattered: MysteriousForce Pulls Back NASA Probe In Deep Space
On Thu, 05 Oct 2006 23:11:49 -0400, jonathan wrote:
wrote in message ups.com... raven1 wrote: And your point is...? Not that the probe has discovered where the dark matter starts... no, but instead that when C. S. Lewis wrote about "God's quarantine regulations", he didn't know the half of it! God knows how clever humans are at getting around limits. After all, He destroyed the Tower of Babel. "Heaven, even the heavens, are Gods; the Earth He has given to the children of men" - and so the probe is just now bumping into the firmament! Those Weekly World News stories about the Hubble Space Telescope taking pictures of angels in Heaven, while perhaps not true, are, apparently, not utterly implausible. Interstellar travel is a waste of time, the only thing 'out there' is the past. Um... what? -- Mark K. Bilbo -------------------------------------------------- "As hip as it is for outsiders to blame New Orleans for everything bad that happened during and after Hurricane Katrina, the truth is that the people who lived here were much more prepared for a big storm than the federal government that promised us flood protection." [Jarvis DeBerry] http://makeashorterlink.com/?V180525DC "Everything New Orleans" http://www.nola.com |
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"Scientific" Dreams Of Travel To Stars Shattered: MysteriousForce Pulls Back NASA Probe In Deep Space
On Thu, 05 Oct 2006 16:53:42 -0600, Joe Strout wrote:
This is really exciting research. If the effect is real, it could indicate the need for revision our theories of gravity -- and that, in turn, is likely to have repercussions on other theories (dark matter comes immediately to mind). However, what's really astonishing is the level of ignorance required to read this article, and then type a subject line like "Dreams Of Travel To Stars Shattered". How can you read about an acceleration of 6 mph per century, and not see that this would be absolutely no impediment to interstellar travel? Because he's so dense, he actually bends rays of light... -- Mark K. Bilbo -------------------------------------------------- "As hip as it is for outsiders to blame New Orleans for everything bad that happened during and after Hurricane Katrina, the truth is that the people who lived here were much more prepared for a big storm than the federal government that promised us flood protection." [Jarvis DeBerry] http://makeashorterlink.com/?V180525DC "Everything New Orleans" http://www.nola.com |
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"Scientific" Dreams Of Travel To Stars Shattered: MysteriousForce Pulls Back NASA Probe In Deep Space
On Fri, 06 Oct 2006 05:11:38 -0700, 2738 Dead wrote:
On Fri, 6 Oct 2006 04:31:17 GMT, (Henry Spencer) wrote: In article , Orval Fairbairn wrote: A space probe launched 30 years ago has come under the influence of a force that has baffled scientists and could rewrite the laws of physics... Could it be fluid dynamic drag, due to traveling through the miniscule solar atmosphere way out there? There is, after all, some interstellar gas there. Not enough -- by multiple orders of magnitude -- to have a detectable effect, even one this small. Not via known mechanisms of drag, anyway. There is currently some work underway (note that the quoted news report is several years old) to try to define exactly what *direction* the mysterious force is acting in: toward Earth, toward the Sun, along the antenna axis, or against the direction of motion. (These are similar but not quite identical directions.) This could reveal the general nature of what's going on: + Toward Earth would almost certainly mean that the "force" is actually some kind of error in the tracking or data analysis. + Toward the Sun would probably mean new (gravitational?) physics. + Along the antenna axis would almost certainly mean some kind of engineering issue, like gas leakage or photon thrust from radiated heat. Because the spacecraft spins around the antenna axis, most any force produced by the spacecraft acts, on average, along that axis. Thrust from radiated heat is a particularly contentious issue because modeling where all the radiated heat goes is tricky; not everybody is convinced that this explanation has been thoroughly ruled out. + Against the direction of motion would probably mean some kind of drag, although heaven knows what would be doing it. Why, it must the the aether! No, silly, it's bumping into angels! -- Mark K. Bilbo -------------------------------------------------- "As hip as it is for outsiders to blame New Orleans for everything bad that happened during and after Hurricane Katrina, the truth is that the people who lived here were much more prepared for a big storm than the federal government that promised us flood protection." [Jarvis DeBerry] http://makeashorterlink.com/?V180525DC "Everything New Orleans" http://www.nola.com |
#29
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"Scientific" Dreams Of Travel To Stars Shattered: Mysterious Force Pulls Back NASA Probe In Deep Space
"Gene Ward Smith" wrote in message
ps.com... Orval Fairbairn wrote: Could it be fluid dynamic drag, due to traveling through the miniscule solar atmosphere way out there? There is, after all, some interstellar gas there. What about cold dark matter? Isn't that one of the new Prismacolor selections? |
#30
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"Scientific" Dreams Of Travel To Stars Shattered: Mysterious Force Pulls Back NASA Probe In Deep Space
Mark K. Bilbo wrote: On Thu, 05 Oct 2006 16:53:42 -0600, Joe Strout wrote: This is really exciting research. If the effect is real, it could indicate the need for revision our theories of gravity -- and that, in turn, is likely to have repercussions on other theories (dark matter comes immediately to mind). However, what's really astonishing is the level of ignorance required to read this article, and then type a subject line like "Dreams Of Travel To Stars Shattered". How can you read about an acceleration of 6 mph per century, and not see that this would be absolutely no impediment to interstellar travel? Because he's so dense, he actually bends rays of light... Don't call him a star. Perhaps a neutron star or black hole but not a star... -- Mark K. Bilbo -------------------------------------------------- "As hip as it is for outsiders to blame New Orleans for everything bad that happened during and after Hurricane Katrina, the truth is that the people who lived here were much more prepared for a big storm than the federal government that promised us flood protection." [Jarvis DeBerry] http://makeashorterlink.com/?V180525DC "Everything New Orleans" http://www.nola.com |
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