Airbrush

The only expansion in the universe is between superclusters of galaxies. Within a cluster, galaxies may collide or orbit their center of mass indefinitely. We and Andromeda are both moving towards the other. Superclusters (clusters of clusters) are by definition gravitationally bound. We are members of the Virgo supercluster which is about 110 Million light years across. http://en.wikipedia.org/wiki/Superclusters

Our galaxy is moving around the center of the local group in an irregular orbit, pulled by other galaxies in different directions. It is moving relative to the center of gravity of the local group, 552 to 630 km/second. http://en.wikipedia.org/wiki/Milky_way

The Big Bang theory is as close as we can get. If you can figure out a single theory of "everything", then you deserve a nobel prize!

"....[What] if space is expanding at more than the speed of light then why does light reach us in the first place? If it is space that is expanding, and not galaxies moving at that speed, then how does the light outrun the growing distance? " Certain points of the universe are moving away from each other at beyond the speed of light. Light reaches us only if it had time to travel the distance. Light will never "outrun the growing distance", if the distance is great enough.

If you had gone to Wikipedia.org and typed "lunar month" you would have gotten your answer. Amazing how much Wiki knows. Wiki says a lunar month is approx. 29.53 days. Try Wiki first. If that doesn't work, ask here. http://en.wikipedia.org/wiki/Lunar_month

Thanks for your explanation!

According to String Theory, all matter is composed of vibrating "strings". What are the size and dimensions of a string? I suppose they are 2 dimensional with no thickness, only length, as the name implies. How long would the string be in Planck Lengths? (A Planck length is approx 10^-20 of the diameter of a proton.)

Sure it would become liquid, but only for an instant as it is again frozen solid. It would not have much cooling effect because space is a near vacuum, no convection.

Virtual particles blip in and out of space, but as particle and antiparticle, then they combine again to cancel out. Where is the antimatter universe that is going to cancel us out? Is it invisible? "...virtual particles are often popularly described as coming in pairs, a particle and antiparticle, which can be of any kind. These pairs exist for an extremely short time, and mutually annihilate in short order. In some cases, however, it is possible to boost the pair apart using external energy so that they avoid annihilation and become real particles....." http://en.wikipedia.org/wiki/Virtual_particles

Good questions. I'd like to know approx how many stars within a radius of various distances from us. For example, you mentioned 12.5, 50, and 250 light years. How many stars within a radius of each of those? Also what is the size distribution of our neighbor stars? What percentage are the size of our sun? Smaller? Larger? Thanks for the link, which answers my last questions. There I find that 88% of all stars are smaller than our Sun. 3.5% of all stars are the size of our Sun, and only 8.5% of stars are larger than our Sun. So Kepler should have complete data about Earth-sized planets, from 91.5% of stars in its' field of vision, that is from stars smaller or equal to our Sun, after about 5 years of operation. That is because even after 3 transits, it takes over a year for the investigators to catch up to all the data coming in. The last update in 2011 was for only 6 months of data gathering, and that is over 2 years after it was launched into space in April 2009. They are that far behind. Also Wiki reports noise levels higher than anticipated, which means a mission twice as long as expected: "Since the signal from an Earth size planet is so close to the noise level (only 80 ppm), the increased noise means each individual transit is only a 2.7 σ event, instead of the intended 4 σ. This, in turn, means more transits must be observed to be sure of a detection. Recent estimates indicate a 7-8 year mission, as opposed to the 3.5 year planned, would be needed to find all transiting Earth-sized planets. The spacecraft has enough fuel for such a mission, but there is no funding for it so far." http://en.wikipedia.org/wiki/Kepler_(spacecraft)

Good answer Moontanman. We have no idea how planetary systems are structured in general. We only know about our own solar system. Kepler will give us a better idea. So much can happen in a planetary system while it is forming. Large planets seem to form almost anywhere, and they pull on their fellow planets, throwing some out to the edge of the system in irregular orbits, and throwing others towards the star. This can rearrange a system greatly over Billions of years. When Kepler reveals this, remember where you heard it first.

13 Billion years is a long blip. "Blip" is not the word. Virtual particles blip in and out very fast.

Kepler is devoted to finding Earth-sized planets, or even smaller, if possible, with special interest in the habitable zones. Most stars in Kepler's view are smaller than our Sun, so after 3 years of gathering data, they should have confirmed most of the planets with periods of one year or less, and thus mission accomplished. A few extra years would be nice, if affordable. As Marcy said, "The best is yet to come!" How could congress refuse to extend the mission a few more years after the astonishing findings? Trivia question: What is the closest and most distant stars in Kepler's field of view? Correct me if I am wrong, but I think compactness of planetary systems is random. It's just how the original accretion disk formed. Anyone know of any rules about systems around stars of various sizes?

By random chance. Kepler 11 and the other first discovered planetary systems, are compact. As the sampling period gets longer, less compact systems will probably be discovered. They need 3 transits to confirm a planet, and that would take 3 years for a system like our own.

Unstable means not long lasting. If "nothing" existed anywhere, it would be like a magnet, or vacuum, for anything else. It would decay to something very fast.

The idea of life inside a black hole seems preposterous. If it leads to another dimension, the path is very extreme, probably not survivable. Your link is blank.

Very interesting. Something does not come from nothing. What may appear to be nothing is actually something.

I'm sorry I don't have any source, just I thought I recalled reading spy satellites can read license plates. What exactly spy satellites can resolve is top secret. If they are also steathy is top secret, unless anyone knows where that info is. Just guessing.

I edited my answer above. I believe the answers are yes, and no. Such space telescopes can distinguish human faces on Earth, even license numbers on cars, but the satellites don't have stealth that I know of, does anyone know? It is possible the military sent up stealthy spy satellites without announcing it.

It sounds like you are asking can spy satellites distinguish human faces on the ground?, and yet be undetectable to ground telescopes? I believe the answers are yes, and no. Such space telescopes can distinguish human faces on Earth, even license numbers on cars, but the satellites don't have stealth, and can be seen by ground telescopes.

Interesting observation. I had always believed SMBH formed long before any stars or galaxies. The only way that much matter can be close enough together is soon after the moment of the Big Bang.

Thanks for the spelling. "Most math sequences could be natural." But not all. Rather, few are natural. In fact, there should be an infinite variety of sequences that are obviously not natural. A sequence of prime numbers is just one of them. All you need is a pattern that is obviously not natural. Dots and dashes that are in a complicated, but ordered sequence, is a start. How about a complicated mathematical equation that repeats, or it changes slightly in such a way that the changes are in an artificial pattern. Or the structure of the DNA molecule that repeats? The list should go on and on.

A series of prime numbers is not the only way an ETI could signal their existence. (BTW, why would they? It's like saying "Here we are, come and bother us.") Many mathematical number sequences could do the same job, such as some kind of Morris Code.

Is the accelerating expansion of the universe only experienced between superclusters? Do superclusters also fall apart, or do they remain gravitationally bound? If the expansion is only between superclusters of gallaxies, then it almost seems irrelevant to us, since our supercluster dominates our local experience. Our universe, out to the edge of our supercluster (10s or 100s of light years out) is not expanding at all.

Yes it seems like 2 miles of ice is nearly the same as 2 miles deep of water for an asteroid. It would easily punch through the ice and instantly heat the area enough to melt and vaporize the nearby ice very quickly. Your ice impact theory is I think one explanation for the disappearance of the Clovis people and mega-fauna from North America, over 10,000 years ago. If there was over a mile deep of ice, it could absorb all the impact or Tunguska-like air blast, then evidence melts away.