If the info given in sciencemonster.com (see the extract below) is true, why man-made satelites are required?
602917
Yes.\nThe moon rotates at the same speed as it revolves. So, by the time it covers some distance in revolution, it has moved about the same in rotation. Easy to understand with a diagram.
278734
*sigh* Once again, I'll link to the Bad Astronomer page debunking the myth that the moon landings were a hoax, mostly for the benefit of mrkit99.\n\nAnd remember, as a rocket scientist I know said, "Of course the moon landings were real! Do you have any idea how much harder it would be to fake them than to actually go there?!?"
69062
I thought I read once that there is some sort of laws to stop the private sector from going up there, the moon that is. Same basic protection laws that govern Antartica. Permits and approval required....
643921
Sean is right but it was manufactured that way as a perfect observation post from the aliens inside it observing us.\n\nthe moon is an artificial satellite and is hollow.
984768
Not only do they search for radio signals, but they search for patterns or data within the signals.\n\nThis is accomplished with many listening stations and some distributed resource calculations.  They get volunteers to run some of the code on home PCs.\n\nThe code executes a Fast Fourier Transform and converts the raw signal into frequencies.  Noise is quickly discernible from a signal.  Then it has to be proved that this was not from a terrestrial source of from a man-made satellite.\n\nSo far no luck.
285231
why are u posting this in the astronomy and space part of a science and mathematics section of this site when clearly its a religous/cult/retard that needs a life question?oh ya  roswell doesnt have shit even if it was aliens what does that matter.what if the government was protecting from something that would make life horrible and completely worthless.
746511
Dear Sir:\n\nWhile there have been some actual transmissions from Earth to the Solar System seeking echos, and some of this might still be going on in a coordinated fashion, as I understand it, the primary mission of the existing radio telescopes is to "Listen" to upper wavelength radio emissions from gas clouds, and other phenomina in the universe. Of course, once some interesting\nradio emissions are detected, a full spectrum scan of the target is most likely conducted to determine the full extent of radio\nsignals from that source.\n\nOther radio transmissions are made from Earth to our traveling Space Probes and Robotic Explorers at various locations in the Universe. A continual litany of telemetry, television and voice signals also flows between the Space Station and Ground Control Center to keep a constant watch on the health, status, and activities of the space crew, mission, and the station itself.\n\nI will defer to someone from one of those positions for an\nanswer as to the power and frequency of transmissions from Earth to the Space Station, Earth to the Robot Explorers, and Earth to the existing Space Probes way out in deep space.\nMy guess is that these various transmissions take place on frequencies between 2,500 Mhz and 40,000 Mhz. That is a \nvery large radio spectrum. \n\nSince my response turns around your question, in that I am telling you that the biggest radio telescopes listen rather than\ntransmit, let me also tell you that the biggest radio telescopes are not simply single structures at a given location. In recent years a scheme for the linkage of two or more radio telescopes was developed. Therefor, the biggest radio telescope would be an electronic combination of the signals from most of the largest installations on Earth. A lot of work has been done in that vein in recent years. Using more than one receiving antenna provides an easy means for researchers to filter out local ground (earthbound) noise generators and radio disturbances. Signals heard at the same time by widely separated receiving antennas (and equipment) are most probably from the sighted target source (assuming both antennas are aimed at the same target). It is also interesting to know that the radio signals that are received require a vast amount of processing to be identified and detected. The processing of the radio telescope incoming signals takes a huge array of computers and some very complex software programs to yield useable data.\n\nYes, radio waves do go on forever. However, their strength at the point of interception decreases by the square of the distance from the source. So, the strength of radio waves become very, very weak as you move into distances like 100,000,000 miles.\nThe wave front would continue out like rings of water in a pond until they hit something and bounced back off of it. In that sense,\na portion of the radio wave would not go on forever, but would become a new wave moving in the oposite direction from the new source (which was the object that the wave struck). The\nrest of the wave front would continue on until it struck something, and we repeated the above scenario. The exact same thing happens to signals transmitted from a sonar transducer in the water. Those devices are used to detect the depth of the bottom of rivers/oceans (depth finder), fish in the water (fish finder), or even other vessels (sub hunting). Sonar, uses sound waves and not radio waves, but the principle is almost the same.  Sound waves radiate out. Nearby echos are strong enough to be detected with existing equipment and are plotted and displayed on information screens. Some echos are so weak coming back that the existing equipment cannot detect/plot/or display  them.\n\nRegards,\nZah
552042
No, it's the stuff of the lunatic (no pun intended) fringe.\n\nHowever, if you want to see some evidence, go to www.badastronomy.com\n\nAll the supposed "evidence" is flawed.\n\nI think subsequent, unmanned trips have inadvertently photographed the space junk left behind on the lunar surface.  It couldn't be there if we hadn't left it.\n\nThe only piece of proof you'd need is for an unmanned probe to photograph the flag we left.
1045091
QUOTE-----"The photo must be by telescope from the Earth to the moon! If no one can find any recent photos then the moon landings are a massive hoax!"\n\nTo remind u and other readers...we CAN'T see the lunar rover or whatsoever using our telescope on earth.No matter how BIG the telescope is, we still CAN'T see it because of atmospheric blurring.\n\nEven HUBBLE can't see it...because that landing site (flag and all that) is so SMALL.... and MOON is MOVING so fast.\n\nIt's just like trying to see a COIN when you are travelling with an AEROPLANE high in the SKY\n\nDID U GET IT? OR U NEED ME TO REPEAT IT AGAIN?
129439
I guess it might depend on what makes a satellite important.  The GOES (Geosynchronous Orbiting Earth Satellite) series of satellites continuously monitor our weather and take various pictures of clouds for weather forecasters to use.   The GPS constellation of satellites provides useful (perhaps even critical) positioning information to millions of users.  SARSAT is used to pick up distress beacons from mariners and aviators.   Galaxy 5 is a very widely used telecommunications satellite for the mainstream media.\n\nMany "important" satellites already have back-ups in orbit, ready to be moved into position should its predecessor fail.  Also in the case of DirecTV and XM radio, they have a spare or two in orbit as well since they would stand to lose a very large portion of their subscribers should they have an extended outage...sort of an insurance policy.\n\nSatellites are used for many different purposes, virtually all of them important since it costs so much money to launch them into orbit.
98059
The short answer is: No one really knows, since the details are classified. Also, the current satellite performance is probably not as good as what it CAN be. \n\nI think that comparing what astronomers are able to do with what the best satellites are able to do can be a bit misleading. \n\n1. The space telescope does not have to look through the air, with the water vapor and turbulence and dust. The space telescope has only the very outer reaches of the atmosphere to look through. \n\n2. The space telescope and ground-based astronomers do not have at their disposal anywhere near the resources that governmental organizations do. For example, the space telescope was not even calibrated, because there was so little money! It was only because of heroic efforts and a few minor miracles that the space telescope was brought into focus. The space telescope is basically a toy, and has barely been able to get funded for the last few years, and might be soon decommissioned. \n\n3. Astronomers just do not have the interest, the background, the training, the knowledge, or the resources to command the type of bleeding-edge technology that governments do. Astronomers for the most part are mired in phenomenology, and do not worry much about the details of pedestrian things like optics. Optics is, in general, disparaged by astronomers and left to the "engineers" and other lesser beings like mathematicians, physicists, statisticians, computer scientists, etc. Basically, astronomers hurt themselves with their attitudes and their culture. \n\n4. No responsible government is going to announce what they are capable of seeing with their satellites. All of this material is very closely held at best, and most likely highly classified. \n\n5. It is well known (or at least often reported in the newspapers, so it might not be correct) that spy satellites are so big and so heavy because they bring a large reserve of fuel with them so that they can be lowered and raised as needed to see various features and details. Apparently, they do not always orbit at the same altitude. \n\n6. It is quite possible to combine imagery from platforms such as multiple satellites, planes, high altitude balloons, etc. to improve resolution considerably. It is hard to know the extent to which this is done, or if it is done, because of course the area is shrouded in secrecy, so we do not know. But the question was, how detailed CAN it be? Well you COULD use multiple sensors on multiple platforms, unlike the Hubble telescope (in fact, multiple sensors on the ground are able to beat Hubble now). \n \n7. As a gross upper bound on resolution limits, look at the mutually agreed upon limits on size of warheads etc by the Russians/FSU/USSR and the USA, for example (typically, the silo doors would reportedly be opened to permit treaty inspections, according to newspaper accounts anyway). These specifications in the treaties imply MUCH higher resolution than the some of the numbers given here by others. And remember, these are the mutually agreed-upon resolutions by two very suspicious adversaries, who do not want to give anything away. Both have to be able to achieve these resolutions, and probably are capable of far better resolution. \n\n8. Having looked at Dawe's limit, and knowing a bit about resolution, I can tell you that it is not particularly useful as an indicator of achievable resolution. How close we are able to come to ultimate resolutions depends on how many resources we are willing to spend, and again since it is classified, it is difficult to know.\n\nTherefore, to answer the question how detailed can satellite imagery be? The answer is, VERY. How detailed is it? We do not know, since it is classified.
512027
Many are familiar with the claim that the Great Wall of China is the only man-made object visible from space or from the moon with the naked eye. This is simply not true.\nFrom a low orbit of the earth, many artificial objects are visible on the earth, such as highways, ships in the sea, railroads, cities, fields of crops, and even some individual buildings. While at a low orbit, the Great Wall of China can be seen from space but it is not unique in that regard.\n\nFurthermore, when leaving the earth's orbit and acquiring an altitude of more than a few thousand miles, no man-made objects are visible at all. NASA says, "The Great Wall can barely be seen from the Shuttle, so it would not be possible to see it from the Moon with the naked eye." Thus, it'd be tough to spot the Great Wall of China or any other object from the moon. Furthermore, from the moon, even the continents are barely visible.
868933
NASA experiment a lot on this issue, maybe by login onto their site you'll find the info you're lookig for, luck..☺
552669
Some of the sattelites Google has been forced to use are quite old, but new imagery is being collected every day. Eventually there will be new high resolution pictures of the whole surface of the planet. I know a guy who is writing messages on his roof so he can see them in the sattelite pictures...he's kind of a nutjob.
266887
Before the NASA satellite orbiting the sun had it's photographic information "pulled" from the web, it showed two distinct and large objects executing a right-angle turn right into the sun.  Planets, asteroids, etc. have no way of ever executing 90 degree turns naturally (as far as human understanding is at this time.) Why the information was pulled off the web--well there are a billion consipiracy theories about that, and I will skip it.  With proper technology, it is obvious to me the sun can be penetrated, and it well may be a portal to another dimension or whatever.  A black hole on "the other side" may appear as a sun here, and vice-versa.  If we exist in a fractal universe, there are three things: here, there, and the boundary between here and there.  This set of three keeps repeating infinitely.  Therefore the sun's energy producing layer may be a boundary to be passed through to get from "here" to "there."  Cool--huh?  Some very excellent minds are hard at work trying to further our understanding of the universe.
1183835
With the current advances in transportation technology, it will be possible it is just a matter of time.  The main problem that space exploration has to deal with is radiation surges caused by solar flares.  They have to develop a proper shielding and detection system that is light enough to launch into outer space.  That is one of the reasons why it is debated whether or not man has even walked on the moon because of the immense amount of radiation that the ship would have been forced to endure would it have traveled that distance.  There are a number of other proofs provided for both sides taht I will not get into.  I think that it is possible and that man will accomplish it if the Lord tarries his coming.
955715
There is an awful lot of info. You are talking about a field to which tens of thousands of people have each dedicated a lifetime of study!  If you are studying for a test, you need to focus on the contents of that particular test.  \n\nA nice site I like that has cursory information on many thing astronomical and space related written for the lay person is the Astronomy Picture of the Day.\n\nhttp://apod.gsfc.nasa.gov\n\nThe archives go back to 1994, with few repeats.