The Pioneer Anomaly |
The Pioneer Anomaly |
Aug 16 2005, 04:27 PM
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#31
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Rover Driver Group: Members Posts: 1015 Joined: 4-March 04 Member No.: 47 |
http://www.planetary.org/news/2005/pioneer_anomaly_faq.html
The planetary society may be checking it out... QUOTE The Planetary Society has committed to raise the funds to preserve the priceless Pioneer data from destruction.
After years of analysis, but without a final conclusion, NASA, astonishingly, gave up trying to solve the "Pioneer Anomaly" and provided no funds to analyze the data. The Pioneer data exists on a few hundred ancient 7- and 9-track magnetic tapes, which can only be read on "antique" outdated computers. The agency is going to scrap, literally demolish, the only computers able to access and process that data in the next few months! |
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Guest_Richard Trigaux_* |
Jan 12 2006, 09:35 AM
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#32
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Guests |
The density of galaxies was determined using the local lens effect, so that it allows to draw a density map of the galaxy. It is as if the galaxy was a glass lens: observing the distortion of the background through it allows to derive a map of the glass lens thickness.
And this allows us to have numeric data on the density of galaxies, not a formula in the style 1/R2 or 1/R3. This in turns allows to solve the differential equation numerically, not algebrically (using numbers and computer calculus, not formulas). QUOTE (ljk4-1 @ Jan 11 2006, 09:42 PM) Johns Hopkins Univ. news release dated 1/11/06 SCIENTISTS "RAVE-ING" ABOUT MOST AMBITIOUS STAR SURVEY EVER An international team of astronomers today announced the first results from the Radial Velocity Experiment, an ambitious all-sky spectroscopic survey aimed at measuring the speed, temperature, surface gravity and composition of up to a million stars passing near the sun. Those first results from the project, known for short as RAVE, confirm that dark matter dominates the total mass of our home galaxy, the Milky Way, team members at The Johns Hopkins University and elsewhere said. The full survey promises to yield a new, detailed understanding of the origins of the galaxy, they said. The results were released at the American Astronomical Society's 207th meeting in Washington, D.C. An image is available at http://www.jhu.edu/news/home06/jan06/wyse.html Very interesting indeed, but they assume that all the stars in the galaxy have elliptic orbits. This is simply not true, and may account with many difficulties. If a majority of the mass is concentrated into the galaxy plane, stars into inclinated orbits will have chaotic trajectories. Even stars in the disk plane will not have elliptic orbits, if the mass is into the disk. The only stars with regular orbits are those in a circular orbit around the center of the galaxy. Why? because they "feel" the mass "under" them (closer to the centre) as a point mass, and the mass "above" (further from the centre) has no influence. (and even this is not sure, it is true only if the galaxy has a spherical symmetry.) So until now I even don't know if a spiral galaxy like ours has a spherical symmetry or a disk symmetry. Maybe all the galaxies are more or less elliptic. However only a precise density map of the supposed dark matter can lead to its state equation, and from there to its physical nature: molecular hydrogen, atomic hydrogen, baryonic objects (ranging from dust to small stars and black holes) or other subatomic particules. If the state equation points at none of these things, so we will have to admitt that there is no dark matter, but some geometric effect. |
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