Category Archives: Nebular Hypothesis

ALMA reveals planetary construction sites

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found telltale differences between the gaps in the gas and the dust in discs around four young stars. These new observations are the clearest indications yet that planets with masses several times that of Jupiter have recently formed in these discs. Credit: ALMA (ESO/NAOJ/NRAO)/M. Kornmesser   Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have found the clearest indications yet that planets with masses several times that of Jupiter have recently formed in the discs of gas and dust around four young stars. Measurements of the gas around the stars also provide additional clues about the properties of those planets. Planets are found around nearly every star, but astronomers still do not fully understand how—and under what conditions—they form. To answer such questions, they study the rotating discs of gas and dust present around young stars from which planets are built..
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Research Shows Asteroids Are Byproducts of Planetary Formation

“Asteroids May Not Be Planet Building Blocks After All” Asteroids have long been regarded as planetary building blocks. But they may actually be byproducts of planet formation, born when violent collisions smashed an earlier generation of objects apart, a new study suggests. Asteroid fragments that fall to Earth as meteorites often contain tiny, round pellets called chondrules that formed when molten droplets quickly cooled in space in the solar system’s early years. Chondrules are found in 92 percent of all meteorites, and are often thought to be the building blocks of planets. Chondrules were part of the protoplanetary disc of gas and dust surrounding the newborn sun that gave birth to Earth and the other planets. A recent study found that chondrules formed about 1 million years after planetesimals — the building blocks of protoplanets — came together. Prior research had suggested that chondrules in some meteorites were probably born when rocks.
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Formation of the Planets: A 1982 Cambridge Perspective [What Has Changed Since?]

“How did the solar nebula evolve to form the Sun and planets? At the present time this is still the big open question, and there is a range of theories from which to choose. None provides a completely satisfying answer since each can only explain part of the observational data  provided by meteorite analysis, planetary astronomy and spacecraft exploration. The theoretical models will be described only briefly since the details are evolving rapidly and soon become obsolete.” Provided by: The Cambridge Photographic Atlas of the Planets by G.A. Briggs and F.W. Taylor Geoffrey Briggs: Deputy Director, Earth and Planetary Exploration Program, NASA Fredric Taylor: Acting Head, Department of Atmospheric Physics University of Oxford.
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The Nebular Hypothesis Is Wrong

Brief Background: “The current standard theory for Solar System formation, the nebular hypothesis, has fallen into and out of favour since its formulation by Emanuel Swedenborg, Immanuel Kant, and Pierre-Simon Laplace in the 18th century.”   Problems With the Outdated Theory: “The physics of accretion disks encounters some problems. The most important one is how the material, which is accreted by the protostar, loses its angular momentum. One possible explanation suggested by Hannes Alfven was that angular momentum was shed by the solar wind during its T Tauri phase. The momentum is probably transported to the outer parts of the disk, but the precise mechanism of this transport is not well understood. The process or processes responsible for the disappearance of the disks are also poorly known. *The formation of planetesimals is the biggest unsolved problem in the Nebular Disk Model. How 1 cm sized particles coalesce into 1 km.
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Planetary Formation Theory In Chaos

Three known planets of the star HR8799 (the light from the star has been blotted out) NASA/JPL-Caltech/Palomar Observatory   Astrophysicists, are being ‘knocked into a cocked hat’ by the results from the planet-finding Kepler space observatory. Almost a thousand new ‘exo-planets’ have been confirmed and another four thousand candidates are waiting to be assessed. So what’s the problem? Well, the original theory of planet formation was derived to explain the only system we knew of at the time—our own. When others were being discovered astronomers expected them to be at least somewhat like our own. That hope has been dashed. The more planetary systems we find, the more our own world stands out as the exception rather than the rule. Naturalism is no great friend of novelty—it likes to see one theory explain all. Weird worlds require weird explanations, and the more the weirdness mounts up the less and less.
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