The route they chose took them through a barren ravine known to the Arabs as Qumran to the spring waters of the oasis at Ain Feshkha. Being a good shepherd Muhammed chased after one of his goats that had strayed up a cliff and got lost. When he found the goat he noticed the opening of a cave in the cliff wall. Curious, but wary of the snakes that would often hide from the heat of the sun in such caves, Muhammed simply threw a stone into the dark cave opening. He was intrigued when he heard the stone make a sharp crack but decided to tell his friends before he went into the cave.

Muhammed returned a while later with a friend of his and the two Bedouin boys found they could not resist exploring the cave, snakes or no snakes. What they discovered inside was collection of several large clay jars and the fragments of several others. Muhammed and his friend were fascinated and could only guess at what treasures might be hidden inside the mysterious jars. With visions of a Princes gold and jewels in their eyes the two boys lifted the lid off one of the great jars and with eager anticipation looked inside.

What they found inside was certainly a treasure but not the hoard of silver and gold they had dreamed of. Instead, the jars contained thin scrolls wrapped in linen that had been coated with pitch and wax. Remarkably, the scrolls were still legible, but the boys could not read the strange manuscripts as they were not written in Arabic. Muhammed and his friend decided their unusual find might still be worth something at the bazaar in Bethlehem.

As the story goes the Bedouins sold a few samples of the scrolls to a merchant in Bethlahem for a mere 20 Pounds, though some say it was 50. Oddly, the next several years saw the samples of the scrolls pass through many hands yet there was little interest in them. Finally, the scrolls were recognized for their incredible historical significance and most of them now reside in the Shrine of the Book in Jerusalem.

What are now known as the Dead Sea Scrolls are a collection of about 900 scrolls including many from several other caves in the same area. Notably among them are the only know Biblical texts dated before 100 AD as well as the Isaiah scroll, The Manual of Discipline, The Copper Scroll and a commentary on the Book Habakkuk. Most of the texts are written in Hebrew, some are written in Aramaic and a few are written in Koine Greek.

The significance of The Dead Sea Scrolls is difficult to estimate as their are still some questions about their exact date of origin. There is also some debate about the way access to the scrolls has been restricted. But there can be no doubt about their effect on our interpretation of the ancient manuscripts.

While most people agreed on the need for a national capital nobody could agree on just where it should be. People who lived in the northern states favored either New York City, Philadelphia or Germantown which is now part of Philadelphia. People who lived in the southern states were unsure about a central government, especially one with a capital city located in the north. For a time Germantown was actually designated as the new national capital but when no action was taken the debate lingered on for years. When George Washington was elected President of the United States in 1789 he was president of a country that had yet to agree on the location of its capitol city

The entire issue was further complicated when Secretary of the Treasury Alexander Hamilton proposed that all the state debts incurred while fighting the War for Independence should be assumed by the federal government. To the people of the northern states this sounded like a great idea since their sates owed quite a bit more than the southern states. But the people of the southern states felt this might give the federal government too much power and there was even talk among some southern states about secession from the union. A vote was taken in the Continental Congress and the proposal lost by a margin of just two votes and it was a bitter defeat that left everybody unsatisfied and searching for answers.

Determined to see things through Hamilton sought out James Madison and Thomas Jefferson and asked to talk to them about the problems their country was facing. Jefferson graciously invited Hamilton and Madison to dinner at his home and the men sat down to see if they could solve their differences on the issues of their day. At this meeting Hamilton suggested that the nations capital stay in Philadelphia for the next ten years and then be moved to a site on the Potomac River near Georgetown as this would be more acceptable to the southern states. In exchange for this he asked Jefferson and Madison to convince two friends to reverse their votes on his proposal. Jefferson and Madison agreed to this and even President Washington was pleased with the plan to place the nations capital on the Potomac River.

And so it was that on July 16, 1790 an act of Congress was passed that established the location of Americas capital city at a place first known to the Native Americans as Conococheague or Conongocheague which is the name of a stream at the sites northern boundary. The capital city was, of course, named after President Washington and the act also gave President Washington the power to define the exact boundaries of the site with an area not to exceed ten square miles. President Washington wisely enlisted the services of French born architect and engineer Pierre Charles LEnfant to survey and plan the city. The D C stands for District of Colombia and is in recognition of Christopher Columbus. Washington D C is now one of the worlds great national capitals and will always stand for freedom and democracy.

The structure of Earths interior consists of rock and metal arraigned if layers. At the center is the solid inner core which is composed of nickel and iron and is 1200 kilometers in diameter. Remarkably, the inner core of the Earth is actually hotter than the surface of the Sun. The next layer out is the outer core and it is compose of liquid nickel and iron. The mantle sits on top of the outer core and is made mostly of dense, solid silicate rock. The crust of Earth rests on top of the mantle and is thin, solid layer of mainly silicate rock.

Earth orbits the Sun at a distance of about 149.6 million kilometers and its axis is tilted 23.45 degrees away from the plane of Earths orbit. The result of this tilt is the change in the climatic seasons here on Earth with the Moons gravity providing the ocean tides. The Earth has an average diameter of approximately 12,742 kilometers with a slight bulge around the equator created by the centrifugal force caused by the Earths rotation on its axis. This bulge makes the Earth about 43 kilometers great in diameter at the equator than if you measured pole to pole. The highest point on Earth is Mount Everest at 8,848 meters above sea level but due to the equatorial bulge the summit of Mount Chimborazo in Ecuador is actually farther away from the Earths center.

The atmosphere surrounding planet Earth is composed of 77 percent nitrogen, 21 percent oxygen and 2 percent traces of other gases including argon and carbon dioxide. Earths atmosphere is divided into five layers starting with the troposphere which begins at sea level and rises up to an altitude of about 16 kilometers. The troposphere is where the weather patterns form and the temperature in the troposphere is relatively mild with a global average temperature at the surface of 15 degrees centigrade. At the top of the troposphere is the tropopause which is the boundary layer between the troposphere and the stratosphere.

The stratosphere starts at the tropopause and extends up to an altitude of about 50 kilometers. Unlike the troposphere which is warm at the bottom and gets cooler as you go up, the stratosphere is cool at the bottom and gets warmer higher up. Within the stratosphere is the ozone layer that absorbs ultraviolet radiation from the Sun. Without this ozone layer life would not be able to exist here on Earth. At the top of the stratosphere is the stratopause which has a temperature of about 3 degrees centigrade, just above the freezing point of water.

Above the stratopause is the mesosphere which starts at 50 kilometers up from the surface of the Earth to an altitude of 80 to 90 kilometers. The mesosphere is too high to be reached by aircraft and much of what we know about it was gained by launching sounding rockets up into it. The data from these rockets tells us that the temperature in the upper mesosphere can fall as low as -100 degrees centigrade. We also know that countless meteors burn up in the mesosphere every day and at night we see them as meteoroids. The mesosphere ends at the mesopause.

The thermosphere rests atop the mesopause and rises up to as much as 1000 kilometers above the surface of the Earth. The thermosphere is also where the ionosphere resides, which allows some radio waves to propagate far over the Earth by reflecting them back down. The thermosphere has a very low density and the International Space Station orbits right through it at an altitude of about 320 to 380 kilometers. Beyond the thermosphere is the exosphere that simply blends into outer space.

Venus is 12,100 kilometers in diameter and has a mass of 4.869e+24 kilograms. This makes Venus similar to the Earth and has often been called Earths sister planet. But the similarities end there. One major difference between the Earth and Venus is that Venus rotates on its axis from east to west, which means if you lived on Venus you would see the Sun rise in the west and set in the east. The atmosphere on Venus is mostly carbon dioxide choked with sulfuric acid and has a pressure at the surface more than 92 times the pressure at sea level on Earth. Unlike the Earth, Venus does not have a magnetic field generated by its iron core. This may be the result of how slowly Venus rotates on its axis. The only magnetic field Venus has is very weak and is produced by the interaction of the solar wind and the ionosphere of Venus.

The surface of Venus is difficult to see through the thick, dense clouds and the first crude images of the surface were obtained using ground based radar. More detailed images were obtained by the Magellan spacecraft which was launched to Venus on May 4, 1989 and spent four and a half years radar mapping 98 percent of the surface of Venus. Later, the European Space Agency launched the Venus Express on November 9, 2005 and on April 11, 2006 it slipped into a polar orbit around Venus. These probes have now provided us with an accurate map of Venus.

Most of the surface of Venus is relatively flat plains created by giant pools of lava. Venus has thousands of small volcanoes and hundreds of large volcanoes many of which are over 100 kilometers in diameter. There are fairly large craters scattered at random all over the surface of Venus. These craters are more than 2 kilometers wide and smaller craters do not exist because smaller meteors burn up in the thick atmosphere of Venus. The map of Venus is dominated by two large highland areas, the Ishtar Terra, where the Maxwell Montes, the highest mountain can be found and the Aphrodite Terra highlands.

More missions to Venus are planned for the future and NASAs MESSENGER spacecraft just completed two fly bys of Venus in October 2006 and June 2007 while on its way to Mercury. A spacecraft called BepiColombo, which was launched by the European Space Agency, will also perform two fly bys of Venus on its way to Mercury. Japan is planning to launch the Planet-C Venus climate orbiter in 2010 and NASA has proposed a spacecraft called VISE the Venus In-Situ Explorer which will actually land on Venus. Once on the surface the Venus In-Situ Explorer will take a core sample and examine it. These mission to Venus will tell us more about the chemical composition and climate on Earths sister planet.

Venus is 12,100 kilometers in diameter and has a mass of 4.869e+24 kilograms. This makes Venus similar to the Earth and has often been called Earths sister planet. But the similarities end there. One major difference between the Earth and Venus is that Venus rotates on its axis from east to west, which means if you lived on Venus you would see the Sun rise in the west and set in the east. The atmosphere on Venus is mostly carbon dioxide choked with sulfuric acid and has a pressure at the surface more than 92 times the pressure at sea level on Earth. Unlike the Earth, Venus does not have a magnetic field generated by its iron core. This may be the result of how slowly Venus rotates on its axis. The only magnetic field Venus has is very weak and is produced by the interaction of the solar wind and the ionosphere of Venus.

The surface of Venus is difficult to see through the thick, dense clouds and the first crude images of the surface were obtained using ground based radar. More detailed images were obtained by the Magellan spacecraft which was launched to Venus on May 4, 1989 and spent four and a half years radar mapping 98 percent of the surface of Venus. Later, the European Space Agency launched the Venus Express on November 9, 2005 and on April 11, 2006 it slipped into a polar orbit around Venus. These probes have now provided us with an accurate map of Venus.

Most of the surface of Venus is relatively flat plains created by giant pools of lava. Venus has thousands of small volcanoes and hundreds of large volcanoes many of which are over 100 kilometers in diameter. There are fairly large craters scattered at random all over the surface of Venus. These craters are more than 2 kilometers wide and smaller craters do not exist because smaller meteors burn up in the thick atmosphere of Venus. The map of Venus is dominated by two large highland areas, the Ishtar Terra, where the Maxwell Montes, the highest mountain can be found and the Aphrodite Terra highlands.

More missions to Venus are planned for the future and NASAs MESSENGER spacecraft just completed two fly bys of Venus in October 2006 and June 2007 while on its way to Mercury. A spacecraft called BepiColombo, which was launched by the European Space Agency, will also perform two fly bys of Venus on its way to Mercury. Japan is planning to launch the Planet-C Venus climate orbiter in 2010 and NASA has proposed a spacecraft called VISE the Venus In-Situ Explorer which will actually land on Venus. Once on the surface the Venus In-Situ Explorer will take a core sample and examine it. These mission to Venus will tell us more about the chemical composition and climate on Earths sister planet.

Our own galaxy, the Milky Way, is a typical spiral galaxy. This means is looks like a great swirling whirlpool with spiral arms extending out from the center. The Milky Way galaxy is 100,000 light years in diameter and our own star, the Sun, lies on the edge of one of the spiral arms. The Sun is about 30,000 light years from the center of the Milky Way galaxy and takes 225 million years to complete one orbit around the galactic center.

According to modern scientific theory the star we call the Sun was formed about 4,500 million years ago. The Solar System originated when gravitational forces caused what is called the solar nebula to collapse and coalesce into a spinning disc with the central mass forming the Sun. The planets formed from large clouds of gas and dust which gradually built up over million of years as they orbited the central mass of the disc.

The central mass continued to build up in size and as it did the gravitational field it exerted grew stronger. As the gravitational field grew stronger the central mass pulled in more gas and dust and grew even larger.
Eventually, the gravitational force became so powerful that the temperature and pressure at the center of the mass rose high enough to cause hydrogen atoms to undergo fusion into helium atoms. This fusion reaction releases enormous amounts of energy and is the source of the Suns power.

Now illuminated by the Suns rays, the planets of our solar system continued to form and transform. All of the planets have undergone a great deal of change since they first accreted. These changes were brought about in a variety of ways, including violent collisions which resulted in craters that can still be seen today. The planets also went through changes caused by volcanism, melting, structural deformation and the release of gases from deep within.

The planets of our Solar System are generally divided into two groups. The inner planets, which include Mercury, Venus, Earth and Mars and the outer planets, Jupiter, Saturn, Uranus, Neptune and until recently the Dwarf Planet Pluto. The inner planets are all characterized by having solid surfaces and are relatively small compared to the outer planets. The outer planets are all characterized by not having a solid surface and are often refered to as gas giants. The inner and outer planets are also separated by a band of asteroids orbiting between Mars and Jupiter.

Comets, meteors and asteroids can also be found orbiting the sun in large numbers from the outer reaches of the Solar System to very close to the Sun. Comets are balls of frozen liquids and dust which often follow eccentric orbits for outside the orbit of Dwarf Planet Pluto and only display their characteristic tails when their orbit brings them closer to the Sun. Asteroids and meteors are both made mainly of rock. The difference between asteroids and meteors is their size, meteors can be as small a grain of dust, asteroids can be miles in diameter and are sometimes called planetoids.

At the outer fringes of the Solar System beyond the orbit of Neptune is the Kuiper belt where at least three dwarf planets orbit. They are Ceres, Pluto and Eris and they are accompanied by millions of smaller objects about which little is known. At this time a variety of spacecraft are either on their way to the far reaches of the Solar System or are planned for the near future. It will be fascinating to see what wonders these space probes will tell us about the Solar System we call home.

We can observe Mercury from the Earth using both optical and radio telescopes, but much of what we know about Mercury is the result of three fly bys performed by the Mariner 10 spacecraft during the 1970s. The Mariner 10 only photographed 40 to 45 percent of the surface of Mercury and the rest has never been seen up close. The photographs the Mariner 10 did send back reveled a rocky, cratered surface similar to the Earths own Moon.

Mercury is about 4878 kilometers in diameter and this makes Mercury slightly smaller than the moons Ganymede and Titan. However, Mercury is more than twice a massive thanks to its relatively high density that is second only to the Earths. This high density is the result of Mercurys inner structure which has a relatively large iron core that may be all or partly molten. The large iron core also generates a weak magnetic field about 1 percent as strong as the Earths. Despite being weak this magnetic field allows Mercury to maintain a very thin atmosphere in what is called the magnetosphere. The magnetic field does this by deflecting the solar wind.

Up until 1962 it was belived that Mercury rotated on its axis once each time it orbited the Sun. This would mean that one side of Mercury would always face the Sun the same way one side of Earths Moons always faces the Earth. Doppler radar observation conducted in 1965 showed this is not so. Mercury actually rotates on its axis three times during the course of two of its orbits around the Sun. This has some rather odd effects especially when combined with Mercurys highly elliptical orbit. If you were standing on Mercury you would see the Sun rise and then grow larger in size. The Sun would then stop in its journey across the sky and reverse its course. After back tracking a ways the Sun would then stop again and resume its original course. The Sun would then appear to shrink in size and drop below the horizon.

The orbit of Mercury gets even stranger as a result of being to close to the Sun where the Suns gravitational field is incredibly strong. As Mercury orbits the Sun the point where Mercury starts a new orbit moves slightly. This is called the precession of perihelion and it can not be explained using Newtonian physics. For a while it was hypothesized that another planet, that was even named Vulcan, was exerting its gravitational pull on Mercury and this was causing the precession of perihelion. This was proved false and the existence of Vulcan was dismissed when Albert Einsteins General Theory of Relativity provided a better explanation.

At present, Mercury is the least studied of the planets but that will soon change. On August 3, 2005 NASA launched a new mission to Mercury named MESSENGER which stands for Mercury Surface Space Environment geochemistry and Ranging. The MESSENGER spacecraft will make three fly bys of Mercury in January 2008, October 2008 and September 2009. The MESSENGER spacecraft will then settle into orbit around Mercury in March 2011. Japan and the European Space Agency are also planning a joint mission to Mercury called BepiColombo which will arrive at Mercury in the year 2019. These spacecraft will use a variety of scientific instruments to tell us more about all aspects of the planet Mercury.

The Sun is composed of 74 percent hydrogen, 25 percent helium and traces of other elements. The temperature at the Suns core which is considered the inner 20 percent, is approximately 15.6 million degrees Kelvin, the pressure is 250 billion atmospheres and the mass density is more than 150 times that of water. Under such extreme conditions nuclear fusion takes place where by hydrogen atoms are combined to from helium atoms. This reaction releases massive amounts of energy in the form of gamma rays and is responsible for the Suns 386 billion billion megawatt power output. During the course of their journey out to the surface these gamma rays are repeatedly absorbed and re-emitted at lower and lower temperatures. By the time the energy reaches the surface is has been reduced to mostly visible light and is carried through the last part of the way more by convection than radiation.

The convection zone is the Suns outer layer down to about 70 percent of the Suns radius. It is an area where thermal convection takes place in the form of great thermal columns. These thermal columns are heated by nuclear fusion taking place in the Suns core and rise up to the Suns surface where they release their energy out into space in the form of sunlight and particles. As the thermal columns discharge their energy they cool and sink back down in the Suns interior where they are reheated and back up to surface again in a great cycle. The tops of these great thermal columns can be seen on the surface of the Sun in the form of what is called solar granulation and supergranulation.

The surface layer of the Sun that we can see is called the photosphere and has a temperature of about 5800 degrees Kelvin. Above the photosphere are five layers that compose the Suns atmosphere. They are the temperature minimum, the chromosphere, the transition region, the corona and the heliosphere. The temperature minimum region extends from the photosphere up to 2000 kilometers and has a temperature of about 4000 degrees Kelvin. This is cool enough for molecules such as water and carbon monoxide to exist and they can be detected by their absorption spectra.

The chromosphere extends from the top of the temperature minimum region up another 2000 kilometers and is named for the Greek word chromo which means color. The chromosphere can be seen as a flash of color right at the start and the end of a total solar eclipse of the Sun. Strangely enough, the temperature of the chromosphere gradually increases with altitude up to about 100,000 degrees Kelvin at the top.

Above the chromosphere is a transition region where the temperature rises rapidly to about one million degrees Kelvin. This temperature increase is caused by what is known as a phase transition of the element helium present in the transition region. The transition region does not have a well defined altitude and is in constant motion. The transition region is not easily seen from Earth but can be observed by space based instruments operating in the far ultraviolet region of the spectrum.

After the chromosphere is the corona which is much larger than the previous layers of the Suns atmosphere and extends far out into space. The corona is characterized by solar prominences which are immense clouds of super heated glowing gas that has erupted from the upper chromosphere. The corona can be clearly seen during total eclipses of the Sun and is very spectacular to see. The corona is composed of charged particles that become what we call the solar wind as they radiate outward from the Sun at 450 kilometers per second and are responsible for the aurora borealis.

Beyond the corona is the heliosphere which is also know as the magnetosphere. The heliosphere is immensely strong and extends far beyond the orbit of the dwarf planet Pluto. The solar wind travels outward along the heliosphere until it collides with the helipads about 50 astronomical units from the Sun.

When observed with the proper filters we can see sunspots on the surface of the Sun. These spots have a lower temperature than the surrounding area and therefore appear dark. Sunspots are areas of intense magnetic power where thermal convection from the interior of the Sun has been inhibited. Sunspots usually form pairs with opposite magnetic polarity and are responsible for solar flares. The number of sunspots varies over the course of an eleven year solar cycle.

The Sun has been active for about four and a half billion years and has used up about half of the hydrogen fuel it started with. The Sun will continue to burn for about another five billion years after which it will start to force helium to under go nuclear fusion into heavier elements. This will cause the Sun to swell up in size to the point of consuming the Earth and more as it becomes what is called a red giant. A billion years after becoming a red giant our Sun will finally collapse into a white dwarf. Incredibly, it could then take as much as one trillion years to cool off.

They all have their advantages and disadvantages and some similarities. For example, like almost all directories, the index is subject driven. This means the articles are organized by a subject heading and subheadings. This has the advantage of allowing the editor to decide which subjects will or will not be included in the directory. One disadvantage is that building such a directory that is all inclusive would be difficult unless the editor plans to think of a heading and subheadings for every possible subject in the world. Some people would argue that you are better off with a niche type article directory that concentrates on one subject. Other people would state that it is virtually impossible to build an article directory that actually is all inclusive.

There is another article directory format. It does not use a regular article directory script. Instead it uses a forum script . Some of these new forum style article directories simply have a single forum where authors are encouraged to post their articles. Others have a group of several forums designed for articles on a few specific subjects. A new development in this area is a forum that includes 26 subforums which are simply arraigned in alphabetical order. As an example, A Forum, B Forum, C Forum. All an article author has to do is register for the main forum and post their articles in the appropriate alphabetical subforum by subject.
Aardvark articles go in the A forum, Zoology articles go in the Z forum which seems simple enough. This kind of forum has the obvious advantage of being all inclusive as you can post articles on any subject you can think of from A to Z.

These forums are configured so that registered users can add their author bio box in the signature file under the user control panel. This signature file automatically appears at the bottom of every message the user post on the forum including articles. It can include information about the author and the authors copyright policy as well as links to the authors homepage or websites. Visitors can copy and paste the articles on to their own websites as long as they adhere to the authors copyright policy which usually means keeping the links to the authors webpages active.

From the article authors point of view there is another advantage to these forum style article directories. Registered users can post their messages and their articles and they will appear immediately. There is no need to wait for approval by an editor and in most cases users do not have to wait for approval by the forum moderator either.

These forum scripts usually also have an rss feed generator that visitors can use to subscribe to the forum rss feeds. The rss feeds themselves are automatically generated by the forum scripts and usually include the most recent messages posted in the forum. These real simple syndication feeds are a great way for the forum users to gain even more exposure for their articles and websites.