what is the history behind the Keplerian Telescope?
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Listed is a site that has a variety of information on the history of telescopes, including information about Keplerian Telescopes. Also try using Wikipedia.
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Ancient civilizations knew this. Observations of lunar eclipses, plus the fact that the horizon is at equal distances no matter what direction we look made this pretty obvious. The earliest were probably the Assyrians or Babylonians, who developed the first coherent astronomical systems (claims by people that the natives of India were first notwithstanding)\n\nThe issue was not the shape of the earth, but its size, and its place in the scheme of things (at the center or off to the side.) It took thousands of years to displace the earth conceptually from the center of creation to a planet orbiting a star, which was then displaced from the center of the universe to a position in an outlying arm of our galaxy, which itself was displaced from being the entire universe to being the largest galaxy and at the center of the universe to being just another galaxy among billions. So we're just a bunch of hicks from the sticks.
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In the last few years of the 18 cetury (I estimate between 1793-1799) Baron Franz Xaver von Zach ordered a group of 24 astronomers to find a "missing planet" (the planet we know now as neptune) to solve the mystery of uranus's strange rotation.  However, the first asteroid discovered, 1 ceres, was discovered by accident by Giuseppe Piazzi.  Later, there were several other found.  The ammount keep going on through today!
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1572---Tycho Brahe (1546-1601) observes a "new star." (See also here.) \n\n1582---Pope Gregory the 13th reforms the calendar. \n  1588   The "Spanish Armada," a fleet attacking Britain, is destroyed by the British navy and by storms. For the first time Britain is able to claim part of the American continent. \n  Europe and Asia are introduced to American crops--potatoes, tomatoes, corn. Europe´s diet is also gradually enriched by sugar, oranges and pepper, originating in India. \n1609---Galileo Galilei (1564-1642) builds the first astronomical telescope and observes for the first time craters on the Moon, satellites around Jupiter, and the way Venus goes through phases like the Moon (crescent, etc.) .\n\n1610 (approx) Sunspots and their rotation with the Sun were discovered independently by Galileo Galilei, Johann Fabricius (Holland) and Christopher Scheiner.   All used the recently-invented telescope, and Scheiner apparently introduced the safe method of projecting the Sun's image on a flat surface.\n\n---Johann Kepler (1571-1630), using Tycho's observations, formulates his first two laws of planetary motion (3rd law in 1619). \n   After a failed attempt (1586) to establish a colony on Roanoke Island, Virginia (now part of N. Carolina), Jamestown is founded in Virginia in 1607, and the first English settlers land in Massachussetts Bay in 1620 (the "Pilgrims"). \n  1618-1648---The 30 years' war. A century after Martin Luther broke away from the Roman church, a great religious war sweeps Europe, devastates Germany and establishes Sweden as a major military power. In the civil war in England, parliament suspends monarchy 1645-1660, king beheaded 1649.
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Yep, check out the Meade Telescope site.  Great new stuff in astronomy.
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he Very Large Telescope (VLT) has caught a remarkable image of the planet Uranus circled by some of its moons.\n\nThe rings of the planet - which is 3,000 million kilometres away from Earth - are clearly displayed in the image.\n\nThe rings are almost undetectable from Earth in visible light.\n\nThe VLT is located at the European Southern Observatory's Paranal Observatory in Chile.\n\nThe image was obtained in the near-infrared, and includes seven of the planet's moons.\n\nVLT\nVLT is based at Paranal in Chile\nTwo of the moons in the picture, Puck and Portia, were only found in the 1980s as the Voyager probe prepared for its flyby of the planet.\n\nUranus, which is at a distance from the Earth equivalent to 20 times the distance between the Earth and Sun, was first spotted by William Herschel in 1781.
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That would be Halley's comet. I remember seeing it - very blurredly - in 1986.\n\nA bit of background info on the comet it's been known since at least 240 BC and possibly since 1059 BC. Its most famous appearance was in 1066 AD when it was seen right before the Battle of Hastings. It was named after Edmund Halley, who calculated its orbit. He determined that the comets seen in 1531 and 1607 were the same object that followed a 76-year orbit. Unfortunately, Halley died in 1742, never living to see his prediction come true when the comet returned on Christmas Eve 1758. \n\nHalley's Comet Statistics\nPerihelion distance: 0.587 AU \nOrbital eccentricity: 0.967 \nOrbital inclination: 162.24° \nOrbital period: 76.0 years \nNext perihelion: 2061 \nDiameter: 16 x 8 x 8 km
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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.
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why don t you check the following link.\n  http://www.nrao.edu/whatisra/hist_prehist.shtml\n\nThough it is more about the history of radio astronomy, in particular, hope it might be of some use to you as well.
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In the 16th century, Nicolaus Copernicus developed the heliocentric model of the solar system, in which the Sun is stationary at the center, and Earth moves around it. This view of the solar system challenged Ptolemy’s geocentric model, which had been the accepted theory since the 2nd century. In Ptolemy’s model, Earth is stationary in the center of the solar system, and the other planets and the Sun move in complex orbits around it. The Copernican model gradually gained acceptance, for it provided a simpler explanation of the planets' motions.
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Well, that is one hypothesis, which is "conjecture", which is just to say it's a "great big guess".  No astronomical explanation has thus far been a satisfactory explanation, because the hypotheses fail to explain "why" comets orbit the Sun clockwise, while everything in our Solar System rotates counter-clockwise along with the counter-clockwise rotation of the Sun.\n\nMy analysis has determined that our Solar System and the Sirius Binary System are interlocked in an electromagnetic deadly dance of death in which the two systems cyclically and recurrently interpenetrate through each other every 12,000-year period.  Hence, our Solar System is on a collision course with the Sirian System.  This transversion is an extinction level event that I have identified as the Sirian-Solar Reconvergence.  The Sirian Binary rotates clockwise, thus comets are dislodged debris from the Sirian System captured within our Solar System from each Reconvergent event in which the comets retain their original clockwise rotation due to their immense velocity that cannot be overcome by the rotational influence of our counter-clockwise system. \n\nThe Sirian-Solar Reconvergence also explains all the crater impacting that has scared all the solid-body planets.  As the cosmocataclysm ensues all the debris from the various debris belts in both systems dislodge and rains down mass celestial bombardment on every object in both systems, particularly when the Reconvergence reaches its critical vertex of transversion.\n\nAdditionally, the Sirian Solar Reconvergence would completely explain why the planet Venus spins clockwise and backwards (opposite to the spin of the other planets) while revolving around the Sun counter-clockwise, thus creating the unusual phenomenon of one day being one year, because it completes one revolution in one year.  Clearly this is an indication that Venus was originally a planet torn out of its clockwise orbit in the clockwise Sirian System during one of the Reconvergence, and was captured by our Sun.\n\nThe reason why the two systems are locked in this process is because they were formerly unified as one solar system; our system was originally the Osirian Trinary Stellar System.  Sirius B is our original paternal star, Sirius A was the outer star that orbited the body of the system, our Sun (Sol) was technically Sirius C, originally a binary companion with Sirius B at the core of our former Trinary System, and there were originally a total of eleven planets.  The split occurred because Sirius B after depleting its helium as a Red Giant exploded into a Nebula Discontinuity Event, creating the Local Compression Bubble and precipitating the celestial dynamics that tore the system in half.  The two halves journey off to their greatest distance, and then invert and return to the path around the galactic center that they were originally blown apart from, being the recyclic event of the Sirian-Solar Reconvergence.  This cosmocataclysm wipes all human civilization off the face of the Earth and catapults Mankind back to a State of Neobarbarism to begin the slow and incremental process of re-civilization all over again.  It is also responsible for suddenly laying down the Geological Column and entombing the charred bones of beasts and men into fossilization within the stratification, because the event is so violent, catapulting the Earth out of its orbit and thrusting the oceanic waters out of their basins, overrunning the continents.\n\nAs our Solar System and the Sirian System near ever closer, signs of the next Sirian-Solar Reconvergence are mounting, being the environmental deterioration of the terrestrial environment, increased volcanism on the oceanic floors that is heating up the seas and affecting the climatic temperatures, the melting of Earth’s and Mars’s polar ice caps, new red spot storms on Jupiter, the addition of a third belt to the Van Allen Radiation Belts that surround the Earth, the vio
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The first telescopes may have been Assyrian crystal lenses[1], but the Visby lenses tentatively suggest that the technology was known to the Arabs and Persians, then to the Vikings, in the 10th century. Leonard Digges is sometimes credited with the invention in England in the 1570s, but usually credit for assembling the first telescope is given to an unknown Dutch spectacle maker in about 1608. Some name that person as Hans Lippershey (c. 1570 – c. 1619), but Jacob Metius and Zacharias Jansen also claimed to have invented a telescope during the same period. Even if Lippershey did not make the first one, he publicized it. Galileo Galilei made his own telescope in 1609, calling it at first a "perspicillum," and then using the terms "telescopium" in Latin and "telescopio" in Italian (from which the English word derives). Galileo is generally credited with being the first to use a telescope for astronomical purposes. Galileo's telescope consisted of a convex object lens and a concave eye lens, which is universally called a Galilean telescope (used as a viewfinder in many simple cameras). Later, Johannes Kepler described the optics of lenses (see his books Astronomiae Pars Optica and Dioptrice), including a new kind of astronomical telescope with two convex lenses (a principle often called the Kepler telescope). Optical interferometer arrays and arrays of radio telescopes were developed much more recently. Telescopes have been around for a while.
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Earth Centered Universe.\nI have learned a lot by using this software.  It is a planetarium program of the stars viewed from Earth.  It is very easy to manipulate the program, changing direction and zoom, and moving forward or backward in time.  In doing so you learn why things work the way they do, and where and when objects will be in the sky.\nThe website is http://www.nova-astro.com/ \nand there is a Yahoo Group where you can talk to other users and even the maker of the program at\nhttp://groups.yahoo.com/group/ecusers/
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Kepler's Laws \nIllustration of elliptical orbit of a planet with the sun at the left focus. The semi-major and semi-minor axes are denoted by  and . The shaded triangular area element is needed for the discussion of Kepler's second law. Perihelion and aphelion are respectively the points on the orbit nearest and farthest from the sun. Note that at perihelion and aphelion the velocity is purely tangential, i. e., the velocity component along the radius vector is zero.  \nJohannes Kepler, using data compiled by Tycho Brahe, inferred three laws governing the motions of planets in the solar system: \nPlanets move in elliptical orbits with the sun at one focus. \nEqual areas are swept out in equal times by the line connecting the sun and the planet. \nThe square of the period of revolution of the planet around the sun is proportional to the cube of the semi-major axis of the ellipse. \nThese laws were instrumental in the development of modern mechanics and the universal law of gravitation by Isaac Newton. \nShowing that the first law is consistent with Newtonian mechanics is mathematically more difficult than we can undertake in this course. However, the second law turns out to be a simple consequence of the conservation of angular momentum. It shows an elliptical orbit with the area swept out as a planet moves from position 1 to position 2. We estimate this area as , where we have ignored the small unshaded part of the area to the right of the shaded triangle. The distance traveled by the planet in time  is , so the magnitude of the velocity is . However, in computing the angular momentum, we need the tangential component of the velocity, i. e., the component normal to the radius vector . This is simply . The angular momentum is , where  is the mass of the planet. Combining this with the formula for  results in \nSince gravitation is a central force, angular momentum is conserved, which means that  is constant. Thus, we have shown that conservation of angular momentum is equivalent to Kepler's second law. \nKepler's third law turns out to be a consequence of the universal law of gravitation. We can prove this for circular orbits. We know that a planet moving in a circular orbit around the sun is accelerating toward the sun with the centripetal acceleration , where  is the speed of the planet's motion in its orbit and  is the orbit's radius. This acceleration is caused by the gravitational force, so we can equate the force divided by the planetary mass to , resulting in where  is the mass of the sun. This may be solved for Eliminating  in favor of the period of revolution  results in ...This agrees with Kepler's third law since the semi-major axis of a circle is simply the radius .
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so much is written coz u asked an explanation\nThe Copernican Model\n(a.k.a Sun Centered)\nAs we discussed in the previous subunit, the Earth-centered model of the universe, refined by Ptolemy, was set firmly in place in the early part of the first millennium. It was not until 1543 that it met serious competition in the Sun-centered model of Nicolas Copernicus.\n\nCopernicus was born in 1473 in Poland and studied, among other subjects, mathematics and astronomy. He is mainly remembered for formally introducing the idea that the Sun is the center of our solar system. This heliocentric concept (sun-centered concept) was a radical idea for his time. Nearly all contemporary astronomers had adopted the Greek Earth-centered model. It was so radical a concept, in fact, that Copernicus waited until the year of his death to publish his famous essay titled, “On the Revolutions of the Heavenly Spheres.” \n\nCopernicus had two main reasons for asserting that the Sun was the center of our solar system.\n\n1. While the Ptolemaic model was very good at predicting the positions of the planets, it wasn't precise, and over the centuries its predictions got worse and worse.\n\n2. Copernicus didn't like the fact that the Ptolemaic model had big epicycles to explain the retrograde motions of the planets. He knew that this could be explained instead by having the Earth also moving around the Sun.\n\nThe true motion of the planets around the Sun is not uniform circular motion, so Copernicus' model still needed to have epicycles. He had 1500 years of post-Ptolemy data to work with, and needed quite a lot of epicycles to make a new set of accurate predictions for the motions of the planets. \n\nThe main simplification of the Copernican model was that the retrograde loops of the planets as seen from the Earth occur naturally as a result of the Earth's motion combined with the motions of the planets.You worked on this problem in the second part of Activity Two. Here are some illustrations to consider.\n\n\n\nThe Ptolemaic Model\nClaudius Ptolemy lived in Rome around 100 AD. His model of the solar system and heavenly sphere was a refinement of previous models developed by Greek astronomers. Ptolemy’s major contribution, however, was that his model could so accurately explain the motions of heavenly bodies, it became the model for understanding the structure of the solar system. It is beyond the scope of this course to discuss all the complex social and historical implications of an Earth-centered versus a Sun-centered model of the solar system. But nearly all the early models, including Ptolemy’s version of the solar system, assumed that the Earth was the center of not only the solar system, but the entire universe. \n\nThe Ptolemaic model accounted for the apparent motions of the planets in a very direct way, by assuming that each planet moved on a small sphere or circle, called an epicycle, that moved on a larger sphere or circle, called a deferent. The stars, it was assumed, moved on a celestial sphere around the outside of the planetary spheres.
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Go to Heavens Above.  They have a lot of information about the planets, as well as satellites that have been placed in orbit or sent out into the solar system.\n\nhttp://www.heavens-above.com
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Uranus, the first planet discovered in modern times, was discovered by William Herschel while systematically searching the sky with his telescope on March 13, 1781. It had actually been seen many times before but ignored as simply another star (the earliest recorded sighting was in 1690 when John Flamsteed cataloged it as 34 Tauri). Herschel named it "the Georgium Sidus" (the Georgian Planet) in honor of his patron, the infamous (to Americans) King George III of England; others called it "Herschel". The name "Uranus" was first proposed by Bode in conformity with the other planetary names from classical mythology but didn't come into common use until 1850. \n\nGo to the site below.  It has all kinds of info, even on all of the moons.  I hope this helps :)