Domain: aanda.org
Stories and comments across the archive that link to aanda.org.
Comments · 5
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Re:No grav lensing
1) Hmm, I used the algorithm you mentioned earlier for reaching that number, and the gravitational force between Alpha Centauri A+B and Proxima Centauri came out as 4.40 x 10E-13 "Earth gee's" at their current distance of about 13,000 AU. It's a magnitude above what you call "a completely inconsequential force," yet Proxima seems to be in orbit around them as per this paper: https://www.aanda.org/articles.... I don't see how gravitational interactions would cease shortly after this point, especially as star clusters, gas, dust and a lot of dark matter comes into play gravitationally at great distances.
2) We may have different viewpoints on how scientific progress should operate. I consider both the continual refinement of existing theories and investigation of paradigm-shifting hypotheses to be necessary for progressing. But for the paradigm-shifting hypotheses to deserve serious attention they need to be robust enough to explain and predict what the current leading theory does, and preferably some of its shortcomings, in a falsifiable manner. So I find the Electrical Universe model trying to explain way too much with sporadic and tangentially related data.
4) The Big Bang theory makes a bunch of necessary predictions. If, say, the cosmic microwave background radiation was found to have another source, or the universe was shown to not be expanding, or a distant galaxy is blue-shifted, or stars certainly older than 13.8 billion years were discovered... then the theory would be in trouble.
I'm aware of the galactic filaments in the universe, but I don't see how all this leads to an internally consistent alternative to the leading theories of dark matter and general relativity, which I know how they can accurately predict time dilation of GPS satellites and calculate trajectories across space. I remain unconvinced and unimpressed by the Electric Universe.
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Re:Can we moderate submissions?
You appear to be in a state of denial
Astronomy & Astrophysics
The jets of AGN as giant coaxial cablesFrom the paper:
"It also indicates that astrophysical jets are fundamentally electromagnetic structures."
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Re:Plane
Bayesian analysis is a statistical method on the data about the star, not a method of observation. The Wikipedia article in question is talking about this paper http://www.aanda.org/index.php?option=com_article&access=doi&doi=10.1051/0004-6361/200811531&Itemid=129 where data about the movement of a star that was known to already have a planet around it was analyzed using Bayesian techniques to show that there was very likely a second planet. But that isn't an observational technique.
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Re:Asteroid Radar System?
Well, the inverse square law plus the low albedo (http://en.wikipedia.org/wiki/Albedo/) of http://www.aanda.org/articles/aa/full/2002/39/aah
3 638/aah3638.right.html/ most asteroids would necessitate an incredibly bright "light". Anyone feel like whipping out a napkin to do some calculations? I doubt if the visible spectrum would be better than radio wavelengths (after all, we're mainly after large objects, right?). I wonder what the design restrictions would be for a radar which has to wait several hours for an echo would be: I'd guess a fluorescent screen wouldn't be optimal! :-)
To improve results, you'd like to have at least two or preferably more observation points. Looking at NEO asteroid orbits http://neo.jpl.nasa.gov/orbits// projected onto the ecliptic is a scary sight. Looking at them in three dimensions is rather more reassuring.
Right now, I'd guess that Earth-based telescopes are the more economical alternative: easier to service, no pesky problem with energy supply or orbital station keeping. One drawback is that we need longer series of observations in order to resolve asteroidal orbits: hence the recurring "alarm bells" when a newly discovered asteroid rates high on the Palermo or Torino scales, only to be downgraded once more observations are matched to it. -
Re:When will the denials stop?Well, good thing there is this research showing that the Solar wind induced magnetic field around the unmagnetized Earth will save us from a little warming and a lot more heavy radiation from cosmic rays.
Maybe, just maybe, you could also actually read the article you cited, and realize that it actually weakens a common argument against Global Warming. But that may be asking just too much.