Why the asteroids exist is not clear. The "break up of a planet" explaination, I was taught, seems to be falling out of fashion. See http://adsabs.harvard.edu/abs/1979aste.book..975S whose abstract follows: "Hypotheses on the origin of the asteroids are reviewed, and the currently-accepted theory of the formation of the asteroids by an interrupted process of planetary accretion is examined. Olbers' hypothesis of the disintegration of a normal planet, which agreed with Laplacian cosmogony, and modifications of it to account for the large numbers of the asteroids are presented, together with Alfven's asteroid stream hypothesis (1969). The process of dust particle condensation in the asteroid zone and that of Jupiter is considered in the presence and absence of gravitational instabilities in the asteroid zone. It is shown that for both cases, the accretion of larger bodies in the zone of Jupiter could have caused the nonprimary objects in the zone to penetrate the asteroid zone and sweep out most of the preasteroidal bodies, increasing the velocities of the remainder and transforming the process of accretion into one of collisional fragmentation. Observations of the spatial and mass distributions of the asteroids, their rotation, chemical composition and relation to other solar system bodies are compared with theoretical considerations, and it is concluded that the asteroid system can be explained by the present understanding of planet formation." You may want to search wiki etc. also, but I did not. Stimulated by discussion with Walter Wagner (See my footnote in http://www.sciforums.com/showpost.php?p=1515389&postcount=1115 and continue our exchange thru post 1119.) I offer new suggestion for the origin of the asteroids: Perhaps there was a planet in their orbit and it was hit by very high energy particle - one that comes along (in that cross section) very rarely but with enough energy in the center of mass of it and and the nucleus it hit to form a small black hole, (BH here after sometimes). The black hole being large enough to not radiate away before beinging to "eat some of the planet's other atoms" and grow in mass. While the BH mass is small compared to that of the planet, it will orbit the planet with at least first orbit very likely to be and ellipse - perhaps passing thru the solid mass of the planet in the first orbit. (I.e. apogee near the point of collision and perigee inside the planet.) If not then in later orbits it will do so as it will absorb more mass (from an atmosphere?) near perigee than apogee and tend to a decaying quasi-circular orbit. Because of its orbital speed, it will not "swallow the whole planet in one bite" but make curved "straws" as it passes thru the solid mass of the planet. Except very near the surface, these straws will rapidly fill behind the passing BH due to the plastic flow (or violent implosion) of rocks and lava, if any exists deeper inside the planet, and the gravitational pressue at depth within the planet. It is also probably that the decaying orbit is not exactly aligned orthogonal to the planet's equator (spin defined) so none of the initial material eaten comes from the polar regions. Thus, the planet will tend to transform into a spinning disk, bringing the polar regions to the BH's "dinner table" also. Hugh Earth quakes, or perhaps "planet quakes" is more accurate term (at least until same happens to Earth) will occur during the "eating from inside out" process. As the percent of the original planet mass becoming BH increases, the broken pieces of planet crust will better be described as orbiting the BH than conversely. Probably, they will separate and separately orbit the sun before all of the planet can be eaten. Thus we would expect to find asteroids where the planet was and possible a small BH orbiting the sun. It of course would occasionally facilitate the scattering of one of the asteroids into a significantly different orbit, as has obviously happened. The question is can this solar BH be detected? Obviously not by telescopes as BHs do not reflect any light. Very careful observations of the nearer planet's orbits should have small unexplained perturbations. I think they do, but this is not my field. Any thoughts? Is this idea impossible? Is it not adequate to explain the origin of the asteroids and their observed composition (both crustal aggerates and iron types) as well as others? Comments?
My beautiful child (Post 1 explanation of asteroids) has been murdered by a cold ugly fact: The Pioneer Anomoly: "... Since 1998 astronomers have known that the space probes Pioneer 10 and Pioneer 11 are following trajectories that cannot be explained by conventional physics. {That is why it is "ugly."} Launched in 1972 and 1973, respectively, to explore the outer planets, the Pioneer craft are now at the edge of the solar system, with Pioneer 10 being some 86 astronomical units (about 13 billion kilometres) from the Sun. {That is why it is "cold."} But they are not quite where they should be, based on the gravitational pull of the known bodies in the solar system. When the craft were at distances of between 20 and 70 astronomical units, researchers found that the Doppler frequency of microwave signals that were bounced off the craft drifted at a small, constant rate. ... This drift meant that the craft were experiencing a constant acceleration directed towards the Sun, at a level that is 10 billion times weaker that the Earth's gravitational pull. ..." FROM: http://physicsworld.com/cws/article/print/20123 I am astounded and quite skeptical that the total mass of the solar system is known to an accuracy greater than 10E-10 part of Earth's mass. Did not Pluto recently gain two new moons with more mass than that? But, the total solar system mass is no doubt known well enough from these Pioneer observations to rule out the possibility that there is now a small Black Hole orbiting the sun. In a no doubt hopeless and despirate effort to resuscitate my beautiful child, may I suggest that the total mass in Ort Cloud and rock sized asteroids has been overestimated; especially if the rate at which meteors and comets etc are observed enters into this estimation. I.e. if there are less of them, their mutual scattering is less frequent than inferred by observations. The higher observed rate is due to the scattering by the unseen small black hole. - If you will go along with that, I can get you the Brooklyn Bridge for a real low price - PM me.Please Register or Log in to view the hidden image! Can anyone help me save my child (with better idea)? I am thinking that the small black hole has so much momentum when formed that it only makes one pass thru the planet and then exits the solar system is a faint possibility.
Report of the death of my beautiful child (post 1) is based on my misunderstanding of the text quoted in post 2. (I was correct to be skeptical of such precise knowledge of solar system mass.) Wiki gives the mysterious acceleration (the Pioneer anomaly) more clearly: “When all known forces acting on the spacecraft are taken into consideration, a very small but unexplained force remains. It causes a constant sunward acceleration of (8.74 ± 1.33) × 10−10 m/s2 for both spacecraft.” For convenience, I will take this as 9.8E-10m/s2 (so the mysterious acceleration is E-10 of the acceleration of gravity at the surface of the Earth.) The radius of the Earth, r, in AU is 4.1E-5. I will assume that the E10 times smaller acceleration is when Pioneer is at R from the sun with, for convenience, R = 41 AU. Thus the ratio R/r is E6. Now if the black body postulated in post 1 has mass “M” times larger than the Earth mass, this mass can be found from: Anamolus Pioneer acceleration relative to that at Earth surface = E-10 = M (r/R)^2 Or (E6)^2 (E-10) = M = 100 That is, if there is a black hole orbiting the sun with the asteroids, as postulated in post 1, it is about 100 times more massive than the Earth – a reasonable result for the mass of the original mass of the planet the asteroids came from as it orbited between "Earthlike" Mars and much more massive Jupiter. My beautiful child (post 1) may still live and now not only explains the origin of the asteroids, but also the Pioneer anomaly! SUMMARY: Perhaps post 1 kills two mystery-of-physics "birds" with one very dense "stone"! Now two potential murders are: (1) Would an approximately 100 Earth mass black hole, orbiting the sun in the asteroid belt, passing near Jupitor at times be an observable modulator of the planet orbits? Perhaps not because for part of its year, it would be "leading" the planet it was perturbing and part of the year it would be "lagging" and both would be significant only when the black hole is roughly on the sun/planet line and thus accumulate little net effect, but I am way out of my field and too lazy to do the 3 body analysis correctly. Also, Jupiter would not move much due to the perturbation but Mars might be prevented from achieving a nearly circular orbit - Mars has much higher excentricity than all but Pluto, I think. This does, at least superificially, seem to fit together well. (2) But perhaps the lack of observed gravitational lens effects can not be explained and my child will die again? Note however, paradoxically, when a small black hole is near to Earth, it is harder to detect by gravitational lens effect that if it were further away. This is because the effect is only significant, especially for such a small black hole, when the black hole is almost direcly on the line between Earth and the distant background star. I.e. the effect would be very short lived (less than a second is my guess) and seem to be just a "twinkel" in the star intensity, like the atmosphere continusously causes. (again just my guess) I think gravational lens effects normally require hours of tracking the distant star's intensity curve, unless the black hole is so massive that multiple images of the distant star are formed.
BillyT: We know that a lot of the rubble of the asteroid belt is from the constant bombardment of small planetoids that once existed there by small rocks striking them, chipping off the softer outer mantle until nothing but the much harder iron-nickel core remains. You should google on iron-asteroids to get more information. Some of them are quite large, on the order of 100 miles in diameter, somewhat spherical, and nearly pure iron/nickel. I've posted extensively before on the origins of the planets, and it is definitely NOT from small rocks striking each other and sticking together. When that happens in the asteroid belt, they just take a chip off the old block, and whittle it down. Had such rocks slowly accumulated into a spherical mass of small rocks, one still has the problem of how they became gravitationally differentiated while in a molten state, into iron/nickel cores and outer, lighter mantles of mostly oxides. That is, where did the heat come from to melt the cold rocks that stuck together? Radioactive decay is way too small to account for that, and so is the kinetic energy of impact, as shown by a recent [2-4 years ago] Scientific American article microscopically examining struck asteroid pieces [revealing only a tiny amount of shock melt]. The only plausible explanation is that they arose from a large ball of hot gas [Jupiter like] that compressed, radiated away its energy, and 'rained out' its iron, nickel, gold, oxides, etc. that were in a gaseous phase as an admixture to the mostly H/He, forming an inner molten core and outer liquid 'ocean' of great depth of mostly H/He, which later eroded away from the high UV output of nearby OB stars, as would have existed in our stellar nursery circa 4-5 billion years ago. Only the largest gas balls remained as not fully eroded of their H/He, before the OB stars faded, which are now our 'gas-ball-giant' planets. Anyway, as to MBHs causing damage to a planet, when they are travelling at high speed [near c], they are very 'ghost-like' under most theories, akin to neutrinos. Their Schwartzschild radius is extremely tiny. Naturally occuring ones, created by high-E cosmic rays, would harmlessly transit Earth in about 1/4 second, or transit the Sun in about 30 seconds, with maybe only an occasional interaction in which they glommed on to a quark or two. Conversely, at low speed, as if formed in a collider at rest relative to earth, a goodly percentage would be gravitationally bound to Earth, repeatedly passing through our planet where the probability of interaction would be much much higher because of two factors: 1) much greater time-in-transit of the planet, repeatedly done year after year if in orbit about and through our planet, and 2) much greater probability of interaction at low speed, compared to near-c speed [similar to fast and slow neutron probabilities of interaction]. However, our geniuses at the LHC, who wear blinders to all other areas of science and cannot even answer the simplest of science questions such as I've posted at the link below, would rather risk everyone else's quest for knowledge, to satiate their personal blinder-driven quest. http://www.sciforums.com/showthread.php?t=70886 Regards, Walter -------------
