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Everything posted by Cyberia

  1. With NASA's budget being cut back year on year, they have to make do with ever less, even cutting back on missions. They can do "cheap" missions if they are willing to let a spacecraft drift along for years on minimal power. I found that image of Itokawa fascinating. Not what you expect from an asteroid.
  2. Jamongo. Mars gassing off methane every Martian summer is generally believed to be bacteria under the surface. It is believed that some of the moons of the gas giants could harbour life under an icy surface, and the best explanation for chemical reactions on Titan was said to be methane loving microbes. It is possible that the universe is full of life but 99.99% of it is in hostile environments and low down on the evolutionary ladder. There is also the time scale that if aliens had come here a thousand years ago they would have found a primitive people and a thousand years from now we may
  3. Gravity really only does well over large scales like planets, stars, etc. On a quantum scale, nuclear forces like the binding force of an atom replace the almost non-existent gravitational forces on that scale. Temperatures would be the energies of particles produced?
  4. PetTastic. The only way I see expansion working is via a hyperspehere, a four physical dimension sphere with the universe as a "flat" 3D skin on it. As a model of how it works; start off with a ball in the middle, punctured by ten foot long metal spikes. The ball is there merely to hold them in place and can be ignored. Three foot from the centre if a sphere (the expanding universe). Where the metal spikes puncture it, there we will say are galaxies. Now the sphere expands to 12 feet across (6 feet from the centre). The metal spikes are still puncturing the sphere in exactly the same plac
  5. My twopenneth: Enlarge a proton a thousand times and it will fly apart as the binding forces will no longer be able to hold it together. So having a proton a billion, billion times as big as now is not possible. There is also the point that no matter could hold together since the binding forces would be such that even a neutron could not hold together, so no stars, etc. What we call hot is atomic and molecular motion. Surely if it got "hotter" it would expand as that is what usually happens? The laws hold up for all conditions. they may just be more extreme in some cases, like insi
  6. What is space? It is a cornerstone of the big bang idea but no one knows what it is or has even given it any thought. On another forum some time back I went through all the "knowledgeable" people there who believed in the big bang and none could produce an answer. The big bang idea has space as being able to stretch from quantum size to something over 100 billion light years in diameter without changing form in any way, without losing structure, so maybe the speed of light would get ever faster. If space is nothing then endless expansion would not matter since it is merely the distanc
  7. Gravity propagates through space thus causing gravitational lensing, the planets to move in their orbits, etc. In the same way that the sun warms us. No one thinks of the sun's heat conducting through space to us so I don't know why they think of gravity conducting through space to effect other bodies. If you think gravity bends space, then inside a black hole, gravity would bend space back on itself so it could not "escape" and so gravity warping space could not escape either. So you could stand a foot away from a black hole without any problems. However since the propagation of gravity i
  8. The big bang is not a valid theory. It's based on various unproven ideas and some impossibilities. It has failed a number of times and needs some even stranger ideas to keep it going. There is an alternative explanation for the redshift which is more realistic than the crackpot idea of space expanding. Various religions gained respectability solely because of the numbers who believe in them. The same with the big bang idea.
  9. They are created and destroyed with the release of lots of energy. If this happened to any extent, they would blow apart the surrounding matter from violent anti-matter and matter annihilation. It is a rarity because it takes a lot of energy to create them, which is not casually present anywhere.
  10. CraigD. At present a laser beam 2mm in diameter is 1.6 km diameter at the distance of the Moon. How can such diffusion be stopped when we are working over light years? Also, how does the lightsail ship slow down?
  11. Solar cells would get the high initial speed. When they were of little use (somewhere past Mars), they could be discarded and another form of propulsion used.
  12. Just two weeks after the end of its historic shuttle programme, Nasa will today launch a solar-powered spacecraft on a mission to Jupiter. The robotic explorer Juno is set to become the most distant probe ever powered by the sun. The windmill-shaped craft is equipped with three tractor-trailer-size solar panels for its two billion-mile journey into the outer solar system. It will blast-off from Cape Canaveral in Florida at 11.34am local time (4.34pm BST) aboard an unmanned Atlas V rocket. http://www.dailymail.co.uk/sciencetech/article-2022729/Juno-Nasa-launch-probe-Jupiter-just-weeks
  13. Until the early morning of July 6 this year no-one had ever managed to capture footage of a comet colliding with the sun. But three whole seconds of on-the-spot action from Nasa's Solar Dynamics Observatory and all that has changed. http://www.dailymail.co.uk/sciencetech/article-2022465/Blink-youll-miss-The-video-showing-comet-crashing-sun.html .
  14. Solar sails are still beyond us but we could do a low tech equivalent. We can make very efficient solar panels, and make them so thin that they roll up. These could provide electricity, so propulsion to an electric rocket, maybe with permanent magnets to accelerate the particles? They would have to build up much of their speed in inner solar system fly-bys to get the best they can out of strong sunlight before heading outwards.
  15. arKane and Charles Brough. The change required in people if left with free will, will never happen. Most are greedy, selfish, lazy, useless, self interested, and so on. The third world are not going to wake up one morning and decide not to have endless kids, especially if the first world is helping pay for them. It is not in the interest of some countries. The guy in the dress in the vatican; nowhere in the bible does it say that people should produce endless kids. When god says they should multiply, there were two people in the world (garden of Eden) and eight people in the world (after
  16. Earth may once have had two moons - the one that shines at night today and a smaller companion, according to a new theory. A slow-motion collision between the two is believed to have created the mountainous highlands on the moon's far side, as debris from the second, smaller moon piled up. The side of the moon facing the Earth and the side facing away have strikingly different topographies. While the near side is relatively low and flat, the far side is high and mountainous with a much thicker crust. http://www.dailymail.co.uk/sciencetech/article-2022046/Earth-used-TWO-moons--destroyed-g
  17. Space is literally nothing, defined only by what occupies it. Gravity no more bends space than infra-red radiation heats it. The effect of gravity travels through space. No one talks of magnetism bending space.
  18. How do you increase the quality of lives when you are endlessly paying for more people at the bottom? Africa was and always will be a basket case. Oil aside, all muslim countries are little better. we've thrown trillions at these people, many of whom hate us and where has it got us? More mouths to feed and more aid needed. Sure China and India will do well in the coming decades but that does not include helping any other country other than out of pure self interest because they know that "the poor will always be with us" and that in trying to lift them up, countries are dragged down. Short
  19. I tried the Ramjet link and the original blog has gone. The problem with the ramjet is that it needs to get up to a high initial speed to work, maybe a few percent of light speed to collect enough atomic hydrogen to use so it can go even faster. Another problem is that you are building up your own friction in space like running into an endless dense cloud of comparatively very slow moving particles, which will try and slow you down. If you had said to someone living 200 years ago that people would be able to travel from England to America in just a few hours (Concorde) and asked them how t
  20. Basically the use the same principle as dust explosions for their explosive force (propulsion). Aluminium and water are going to form aluminium hydroxide, some of which will be lost in the explosive heat as it denatures at 180.C. AH is used as an antacid, a white chalky stuff, so imagine that slowly building up in your ignition chamber. Since heat can help get rid of it, possibly heated chamber walls? If I were experimenting I would be tempted to try hydrogen peroxide instead of water (which will feed more oxygen into the burning aluminium). Or add a little alcohol to the water. But with s
  21. As pointed out, magnets and electronics don't always mix. Even humans and magnetic fields do not always mix, particularly on a long voyage (permanent magnets would be better than powered magnets which would cost energy, but you cannot turn them off). I thought of perhaps a water filled chamber where each astronaut (separately) could spend maybe two hours a day. The ship's water supply could be used. Or even a fairly tight elastic suit which would need a little exertion to move about and so help stop muscle wastage on long journeys. Or even a little red wine, for medicinal purposes: htt
  22. Discoveries about the universe are coming thick and fast so that if someone writes a book it can be out of date when it appears on the shelves a year or two later. There are a number of sites like Science Daily, Space.com and the like which are helpful though they tend to jump all over the place rather than dealing with specific subjects.
  23. Originally space beyond Pluto was though to be pretty much empty till you got to the Oort Cloud maybe a light year away but now we know about the Kuiper Belt which has an unknown number of planets and assorted large rocks, etc so both the Voyagers have the potential to still make great discoveries. However distances past Pluto are such that they may not come within our life times. The next rocket out that way will be the New Horizons in four years: http://en.wikipedia.org/wiki/New_Horizons .
  24. Another way of looking at it is that if a planet is on our side of the sun or on the opposite side of the sun, it has no gravitational effect on the Earth, as the planetary alignments do not have any effect either. The sun is a thousand times the mass of Jupiter, and far closer to us that any of the larger planets are. The only other body that affects the Earth is the Moon as it is so close.
  25. The human race went from six to seven billion in just 12 years. I would think double that (14 billion) is easily possible by the end of the century, with India, China and Africa leading the field. Certainly water wars are on their way from a shortage of drinking water, with food riots not far behind. We passed the half way mark with the world's oil supply a few years back and now more oil is being used every day so the other half won't take too long to vanish too. I saw an SF film a few years back where civilization had collapsed in the very near future and the story was that suddenly one day
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