http://www2.astronomy.com/default.aspx?c=a&id=2853 "Blasts of gamma rays may have spawned lightning storms as large as the solar system, fusing primordial dust grains into chondrules — the mysterious BB-size spheres that abound in stony meteorites — that, in turn, seeded the formation of Earth and the other planets 4.6 billion years ago." If that happened it surely was spectacular. I'm sometimes amazed of the beauty of lightning storms here in Earth in a cold night, but one of the size of the solar system must be the dream of every horror film fan. I think that earplugs would be very reccomendable Please Register or Log in to view the hidden image!
Hum, My only quibble is that it has been shown in a recent paper that a supernova occurring close by to the early forming solar system created a shockwave (gamma ray blast) that could produce the correct sized chondrules inclusions seen in meteorites. The evidence can be seen in primitive Ningqiang carbonaceous chondrites "inclusions" that contain the products of the short-lived radioactive isotope chlorine-36 (in calcium, aluminium and sodalite)… The rare isotope sulfur-36 is associated with the sodalite. (Sulfur-36 is a natural decay product of chlorine-36 and its association with the chlorine in the sodalite is thus strong evidence for the past presence of chlorine-36). Although it is possible that the irradiation of the early nebular cloud, that formed the sun, could have <b>also</b> created the chlorine-36; the presence of iron-60 provides strong evidence that these radionuclides were produced in a supernova that exploded near the forming solar system and seeded the solar system with these isotopes. And furthermore there is circumstantial computer simulated evidence that such a blast was needed to clear the solar system of `excess material`, thus stunting the growth and orbital characteristics and obit decay of the gas giants. But having said that, the supernova model <b>doesn’t</b> explain the different remelting phases, so yes, it’s an intriguing concept… Incidentally the nebula/protoplanetary disk building phase (I imagine) was less than a million years, so if this gamma ray theory were the case, the neighbourhood around the sum would have to have been a very busy place…
If it's true, the nearby supernova or GRB could have restuctured our protoplanetary nebula more extensively than simply suffusing it with characteristic chondrules. Since this mechanism clearly isn't the norm for planetary system formation, the Solar System - and some other systems in our galaxy of similar age - could be fundamentally different from the majority. Perhaps it has some bearing on why Jupiter & Saturn didn't migrate closer to the Sun, as so many extrasolar giant planets seem to have done - by thinning out the dusty disk in some way, or at least changing its composition? Then again, with fairly massive protostars, there might be internal magnetic processes sufficient to induce similar cosmic lightning and grain-melting in the surrounding protoplanetary disk. Without involving a neighbouring GRB.
Hum, Yeah, that’s the current thinking. Yes, this may be true. Radiation from our own sun may account for the grain-melting seen. Though it doesn’t account for the isotopes, like iron60 - which indicates that a supernova did indeed take place...
Do you think that the amount of radioisotopes in our solar nebula from this hypothetical supernova is related to the evolution of life on Earth (as a source of mutagens)? Or that it significantly affects the amount of radiogenic heating inside the Solar planets today, with all the associated geological processes?
Don’t know, It is debatable if radiation had any role in the emergence of life 4 billion years ago, (those radioisotopes have short half lives, er, compared with half a billion years), It could be a consequence of the chemical reactions taking place , radiation from sun and lightning, or be `radioactive decay` driven (heat) deep within the earth... Worth starting a new thread < added> <sup>60</sup>Fe has a half-life 1.5 × 10<sup>6</sup> years, chlorine-36 has a half-life of only 300,000 years... </added>
Good thing too... the majority of radioisotopes released by artificial fission bombs do tend to decay rather quickly, so that 90% of the iodine-14 fallout from a major nuclear war would be gone after only a month. Strontium-90 would last a century or so; but at least we wouldn't have a planet glowing in the dark for millions of years.
Hum, here some further ... "Comparisons between the predicted abundances of short-lived radioactive nuclides (<strong><sup>107</sup>Pd</strong>, <strong><sup>129</sup>I</strong>, <strong><sup>182</sup>Hf</strong>, and <strong><sup>244</sup>Pu</strong>) in the interstellar medium (<strong>ISM</strong>) and the observed abundances in the early solar system have conclusively showed that these nuclides cannot simply be derived from galactic chemical evolution (<strong>GCE</strong>), if synthesized in a unique stellar environment. It was thus suggested that two different types of stars were responsible for the production of light and heavy r-nuclides. </p> However, new constraints on the <strong><sup>244</sup>Pu</strong> =<strong><sup> 238</sup>U</strong> production ratio used in an open nonlinear <strong>GCE</strong> model, show that the two r-process scenario cannot explain the low abundance of <strong><sup>244</sup>Pu</strong> in the early solar system, and that this requires either than actinides be produced at an additional site, or more likely, that<strong> <sup>129</sup>I</strong> & <strong><sup>244</sup>Pu</strong> be inherited from <strong>GCE</strong> and <strong><sup>107</sup>Pd</strong> & <strong><sup>182</sup>Hf</strong> be injected in the early solar system by the explosion of a nearby supernova." http://xxx.lanl.gov/PS_cache/astro-ph/pdf/0502/0502514.pdf
As I understand after a supernova explosion there is left either a black hole or a white(?) dwarf. Is there a possible way of discovering how exactly far/close the supernova explosion took place? (asking this with the idea of maybe someone finding this important place in our history)
We've made roughly twenty revolutions of the Galaxy since the sun ignited. Since orbits and orbital velocities are quite varied I would doubt there is any way this could be determined.
Blobrana, you are either the ultimate physics geek or a bona fide professor! Where would this forum be without you, mate? @ Ophiolote: that's why I hate it when people discuss the way certain stars would have appeared from Earth in the remote past (as in millions of years ago), or how spectacular such-&-such a star will look to us when it goes supernova, a few million years hence... chances are, none of our familiar present-day stars will be visible from Earth at all within a quarter of our next galactic orbit.
@Ophiolite Yeah, things get messy... "<i>For the first time we have a complete set of observed stars that is a fair representation of the stellar population in the Milky Way disc in general. It is large enough for a proper statistical analysis and also has complete velocity and binary star information. We have just started the analysis of this dataset ourselves, but we know that our colleagues worldwide will rush to join in the interpretation of this treasure trove of information.</i>" <b>128k</b> animgif of the motion of stars/sun, in milkyway, traced backwards in time... http://www.eso.org/outreach/press-rel/pr-2004/images/phot-10c-04.gif
True, white dwarfs can BECOME supernovae - but not result from them. Then again, don't type I supernovae (the type produced by terminal gas accretion on a white dwarf) leave no collapsed remnant at all?
