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Airbrush

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Everything posted by Airbrush

  1. Why don't you agree? The Wiki article said to the effect that for every transit detected, probably there are approximately 215 similar solar systems among that population of stars, but they are aligned so we cannot see transits. There may be more or less, and I would like to hear a plus or minus number, but that is besides the point. I stated "approx 200" because I didn't know exactly. Is approx 200 so far off from 215? Do you disagree with the Wiki article?
  2. "...The probability of a random planetary orbit being along the line-of-sight to a star is the diameter of the star divided by the diameter of the orbit. For an Earth-like planet at 1 AU transiting a Sol-like star the probability is 0.465%, or about 1 in 215." In Wikipedia look under "Objectives and Methods" at about the middle paragraph. http://en.wikipedia.org/wiki/Kepler_mission So if we see an Earth-like planet at 1 AU transiting a Sol-like star, that means there are probably about 215 of those. For every transit we can see means the orbital plane of that solar system is aligned, by chance, with us, and probably 214 others are not aligned with us.
  3. Last gem I heard about Kepler was that it appears that small planets, such as Earth, are even more common than the gas giants. "Again, I don't know the details on this and am only speculating. I wouldn't mind learning the details. If the above is true then the exoplanets Kepler has been able to detect may be a mere tip of the iceberg, no?" You can extrapolate Kepler's findings by multiplying the numbers it detects by approx 200. Kepler has a steady focus on an area of our galaxy thousands of light years away. No it does not watch anything inside our solar system.
  4. I can't believe we haven't heard about this around here. A mountain 284 MILES high on Pluto is incredible! Has this been confirmed?
  5. Does anyone know if a stellar-sized black hole could be located very near us? Is it possible one could be closer than 4 light years, but since they are hard to detect, we simply don't know? Or are we fairly certain there are none nearby?
  6. The CMB did not redshift into the microwave range. The CMB IS visible light that is now redshifted into the microwave range because of the vast distance. A redshift implies great distance from us, the more redshift the greater the distance. The background radiation burst into the visible light range about 380,000 years after the Big Bang, when the universe became transparent, and became visible to the naked eye at that time, but there were no stars around yet, so no life could have evolved. After that was the "dark ages" when hydrogen slowly clumped together into stars and galaxies. The dark ages lasted until about 800 Million years after the Big Bang, when the first stars ignited. They were the first light after the dark ages. Life as we know it needs heavy elements which were not created until the first generation of stars began to supernova. The first stars, "Population III stars", are thought to have been very massive, maybe 100 solar masses and larger with short live spans, maybe tens or hundreds of millions of years. So life could not start evolving until about a Billion years after the Big Bang. "...Before decoupling occurs most of the photons in the universe are interacting with electrons and protons in the photon–baryon fluid. The universe is opaque or "foggy" as a result. There is light but not light we could observe through telescopes. The baryonic matter in the universe consisted of ionized plasma, and it only became neutral when it gained free electrons during "recombination," thereby releasing the photons creating the CMB. When the photons were released (or decoupled) the universe became transparent. At this point the only radiation emitted is the 21 cm spin line of neutral hydrogen. There is currently an observational effort underway to detect this faint radiation, as it is in principle an even more powerful tool than the cosmic microwave background for studying the early universe. The Dark Ages are currently thought to have lasted between 150 million to 800 million years after the Big Bang. The recent (October 2010) discovery of UDFy-38135539, the first observed galaxy to have existed during the following reionization epoch, gives us a window into these times. There was a report in January 2011 of yet another more than 13 billion years old that existed a mere 480 million years after the Big Bang...." http://en.wikipedia.org/wiki/Timeline_of_the_Big_Bang#Dark_ages
  7. The answer to your question is yes, the sky is an illusion. Everything we see is older than it looks because the light from it took time to reach us.
  8. "Earth's oldest fossils have been found in Australia by a team from the University of Western Australia and Oxford University. The microscopic fossils show convincing evidence for cells and bacteria living in an oxygen-free world over 3.4 billion years ago. The team, led by Dr David Wacey of the University of Western Australia and including Professor Martin Brasier of Oxford University, report the finding in the journal Nature Geoscience. 'At last we have good solid evidence for life over 3.4 billion years ago. It confirms there were bacteria at this time, living without oxygen,' says Professor Brasier of the Department of Earth Sciences at Oxford." http://www.sciencedaily.com/releases/2011/08/110821205241.htm
  9. The EM pulse thread got me thinking of this. It is possible to make high speed police chases obsolete, IF all cars manufactured have some kind of sensor on the back bumper. Old cars can be retrofitted with this at not much cost. This sensor is tamper proof and is connected to a system that shuts off the gas, or whatever you need to shut off to bring a speeding car to a gradual stop. You don't want to lock their steering. The police simply point a special device at the speeding car, trigger it and it activates the shut down system in the bad guy's car. Anyone know how to do this?
  10. Thanks for the link. To summarize Starfish, it was a 1.45 megaton nuclear device exploded at 250 miles high and it had an EM pulse larger than expected. 900 miles away in Hawaii, 300 streetlights were knocked out and it damaged their phone system, and set off burglar alarms. The Earth's magnetic field channels the pulse certain directions and proper placement of the nuke can result in worse damage. A few well-placed nukes over the USA could cripple all our unprotected commercial electronics.
  11. Very interesting thoughts. Your post deserves an effective title. How about editing it to correct the spelling of "produced", and rearranging the words for better meaning. I propose "Was more energy or matter produced during the big bang?"
  12. OK, but promise to not try one over my city. All you need to do is explode a nuke miles high. It will destroy all the electronics in a wide area under the blast. In fact a modest nuclear explosion, e.g. one megaton, can destroy electronic circuits to a radius of hundreds of miles! Whereas exploding it on the ground would not affect such a large area.
  13. Then the ceilings can be higher. The walls can be straight vertical up to 8 feet, then the arching dome begins. I think the above argument is irrelevant. Keeping out water from an underground dwelling, however, is a significant issue. Just make sure the inside is very water proof. Water channels can drain away rain water away from and under the house. If the house is 50% below ground level, just build the below ground level like a boat. This would be able to survive a tsunami and the worst storms, in coastal areas prone to such disasters. Probably not good in the Netherlands. Yes windows are important, but there can be sky lights and light can be channeled by reflectors. Electric light is the only light many office or factory workers ever see all day. There can be artificial windows to make the living space seem more traditional and appealing. When people ever live on Mars, they will certainly use underground dwellings and use dirt as a building material.
  14. I like this question. Time after the Big Bang is one thing, and the absolute essence of the word "time" is something else. I think that if somebody was placed in the middle of a vacuum of empty space, before the Big Bang, that person would age. It would be time outside of our own space-time, but a form of time nevertheless. I think it is absurd to assume that there could have not been any form of time before the Big Bang. We know nothing, so far, about what existed before the Big Bang, and nothing should be excluded without scientific reason. There could just as well have been another universe before the Big Bang, and our Big Bang destroyed it, wiping out any trace of what pre-existed our universe. Kturbo, you could make your sentences easier to read by putting at least 2 spaces between sentences.
  15. Have any scientists stated they "can solve" the universe with a few theories? Probably not, but many scientists believe we can "put the universe into perspective" with a few theories, at least the best we can with our observations and analytical abilities. I share your concerns and am in agreement mostly, so I'm just picking at how you are saying it. We still know far too little to make "definitive statements" about the universe, but we can make the best case we can. Big Bang theory is the best we have now, and with time it should improve. The glass is half full, and half empty. The universe will exist regardless of our perspectives. A scientific explanation is more rigorous than a spiritual explanation. Scientists usually will say "Anything is possible within reason, but here is what we think is probable, and it is not engraved in stone but subject to future modifications." Scientists agree on many things, but when the question goes beyond science, they will admit science has its' limitations. I have never heard a reputable scientist say "I know everything about the universe".
  16. Interesting ideas above. I was wondering about using recycled materials for building materials. Also, somehow, using the actual dirt from the property as building materials. If they dig down 5 or 10 feet deep, and somehow press the dirt into bricks with fiber reinforcement and insulating materials, that can be cemented together and stacked in a dome like an ice igloo? The house would be over 1/2 below ground level, and therefore very resistant to storms and tsunamis. If excavating dirt can be done cheeply, you could build entire multi-storied houses underground. Houses would be invisible from view and the environment would look natural.
  17. Thanks for providing a link and I will check out your other discussion. Your link is not working for me. Can anyone else use it? Could you just summarize a few of the other explanations for Hubble redshift? Interstellar dust?
  18. So we can relax. Since engineers are generally not intelligent, they have enough common sense. I love this Alice in Wonderland logic. Hahahaha. Very interesting, thanks for that. So this means that the helium will fully evaporate sometime in 2013 and then the telescope goes dead? Could it ever be serviced by a mission to deliver helium to it?
  19. Thanks for the info. So what is the answer to the original question? "Stephen Hawking pulls back the Black Hole theory for the Universe." What is the black hole theory for the universe? Hawking admitted he was wrong about something? What does that have to do with how black holes evaporate? "...As an example, a black hole of one solar mass has a temperature of only 60 nanokelvin; in fact, such a black hole would absorb far more cosmic microwave background radiation than it emits. A black hole of 4.5 × 1022 kg (about the mass of the Moon) would be in equilibrium at 2.7 kelvin, absorbing as much radiation as it emits. Yet smaller primordial black holes would emit more than they absorb, and thereby lose mass." http://en.wikipedia.org/wiki/Hawking_radiation Seems strange to me. How 2 virtual particles, positive and negative, pop into existence just outside the event horizon, and one particle escapes and the other falls into the black hole as negative energy which will reduce the mass of the black hole slightly. The two particles are so close together, how does one go one way and the other 180 degrees the other way? Also I'd like to know, does the vacuum around an event horizon create conditions that stimulate particle-antiparticles virtual particle production?
  20. Then why are all the red shifts directly proportional to how far away the galaxies are? The distances are estimated based on certain types of supernovas. If strong gravitational fields are causing the red shifts we see, they should be random. Also, the supermassive black holes at the center of galaxies are far too weak to influence the entire galaxy's red shift. What am I missing?
  21. I appreciate your point of view. How can expansion be "observed"? All they have to work with is red shifts. I'm not sure what you mean by there being no consensus among researchers on where to draw the boundary. I'm thinking the boundary is superclusters of galaxies. Where else can it be? Our instruments of measurement are certainly bound by electromagnetic forces, far stronger than gravity. I just can't understand what your point is, and I would like to, if you would care to expound a little more. What else may cause the red shift? Andromeda is one of the very few galaxies that are blue shifted because it seems to be headed towards us.
  22. Welcome aboard Dishmaster. How frequent are the maneuvers? How long will the fuel last to keep doing that? Any advice to posters here on how to get a job in space programs? How did you find your job? I'd rather sweep up around the telescopes for minimum wage than continue to be full time bookkeeper for a restaurant. I don't have much science education, but I've been bookkeeping and accounting for 20 years, so could that number crunching come in handy anywhere you know?
  23. I find it hard to accept the idea of the mass of the entire visible universe compressed into a region smaller than an atom. Yet, Stephen Hawking stated in his DVD "Into the Universe" that the observable universe expanded from smaller than an atom to the size of an orange in one Trillionth of a second after the Big Bang, and that is the inflated expansion. That is being very specific. It is hard to imagine what exactly can cause such a massive amount of matter to overcome its' own immense gravity to fly apart. I prefer to think in terms of expansion starting from a region of undeterminable size. Or some special quantum fluctuation resulted in a kind of super-rapid chain reaction, rather than a traditional supernova-like explosion, that "turned space over" into matter? Or as you propose a supergiant white hole spewing matter into our universe. If Mr. Hawking is correct in stating that after 10 minutes the universe reached thousands of light years across, then at that rate it would reach the size of 42 Million light years across (which is how big it was when the universe became transparent) in only tens of thousands of minutes, which is about one month after the Big Bang. Yet I have also heard that it took 330,000 years for the universe to become transparent after it reached 42 Million light years across and the CMB began it's journey.
  24. I don't understand what you mean by "there is no consensus on the expanding space view". Could you please elaborate? It seems obvious that galaxies are not flying apart. They are tightly bound and have been for Billions of years. How could they be expanding? Also, our solar system does not seem to be expanding over Billions of years. Even if there was a tiny expansion, the effects would be noticed over long periods of time. http://en.wikipedia.org/wiki/Metric_expansion_of_space "For much of the universe's history the expansion has been due mainly to inertia. The matter in the very early universe was flying apart for unknown reasons (most likely as a result of cosmic inflation) and has simply continued to do so, though at an ever-decreasing rate due to the attractive effect of gravity. In addition to slowing the overall expansion, gravity causes local clumping of matter into stars and galaxies. These stars and galaxies do not subsequently expand, there being no force compelling them to do so."
  25. Within the solar system, also within our galaxy, within our local cluster of galaxies, and within our supercluster of galaxy clusters, there is NO expansion. There is not "realy very small" expansion, because gravity wins on small scales. Only superclusters of galaxies are moving apart from other superclusters. There is absolutely NO expansion within a supercluster of galaxies. The expanding motion from the Big Bang and the acceleration from dark energy are overcome by gravity within superclusters.
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