BIOGAS

Biogas is methane collected in a power plant from decomposing animal manure and organic matter, which is sometimes grown specially for this purpose.

ADVANTAGES

1. Firstly, I would like to say that biogas is not a thing to throw away just like that. because, having it will remove the fear that the world will one day face shortage crisis of natural gas. And Government will spend less for imported gas.
2. Secondly, biogas will encourage majority participation in the natural resources trade, that is, there would no longer be a CARTEL comprising of few nations who control the prices of natural gas, in a monopolistic manner.
3. Thirdly, biogas would remove this attitude of some nations in the world today, who engage in the practice of using natural gas to sign agreements to assist the other in time of war, and get a certain percentages of this resources as the benefit.
4. Fourthly, biogas will enable majority of communities in different countries, to participate actively in the power sector, since these raw materials would be extracted from these communities in various countries of the world. And thereby encourage rapid development from the Rural Areas in various countries of the world.
5. Fifth, biogas will encourage large production output, and less production cost, due to the fact that we would no longer need to, for instance, go far to order for the resources needed for production, and no TIME WASTAGE, but limited time, due to the fact that everything would become within reach. Furthermore, INFLATION would be completely reduced to the ground, since we would now have enough resources to set a balance in prices of goods and production cost.
6. Sixth, biogas would bring about JOBs CREATION, and encourages new inventions like chemical experiments, Agricultural development and methods of improving large scale farming. Then, more industries would be created, and a new improved living would be experienced by low income earners in the populace, and this would reduce urban congestion in most countries.

DISADVANTAGES
To mention but few;

1. Biogas would encourage deflation of goods prices, due to many producers, and surplus goods availability to the populace.
2. biogas will bring about high corruption level, from the top to the lowest level in the public.
3. pollution would be on the increase both sound, air, and water pollution. due to many industrial waste materials in the society.
4. There would be FOOD SHORTAGE, in the countries in the world, especially those nations with limited land for food production. And since BIOGAS would involve using raw materials from both cash crops and otherwise. And the fact that not all the nations in the world, have land for farming activities e.g, The nations living on Islands, and others in the deserts. this sets of nations would be denied the necessary means of survival.

Source http://wiki.answers.com/Q/What_are_the_advantages_and_disadvantages_of_biogas#ixzz1e1wUz5SW

How The Solar Eclipse and Lunar Eclipse Occur

An eclipse occurs at those times when the Moon moves into a position of direct alignment with the Sun and the Earth. There are two basic types of eclipses – lunar and solar. Most people have seen at least one total lunar eclipse, when the full Moon passes through the shadow of the Earth. In this case, the Sun and the Moon are on opposite sides of the Earth. If you observe a lunar eclipse (visible only at night at the time of certain full Moons), you’ll see the bright lunar disk turn dark -- sometimes a coppery red color -- for as long as an hour or more.
But the gentle beauty of a lunar eclipse pales in comparison with the truly awesome spectacle of a total solar eclipse, which occurs when the new Moon passes directly between the Sun and the Earth. In the narrow path of totality swept across the Earth by the Moon’s complete shadow (the umbra), daytime briefly turns to an eerie darkness, and during these few precious minutes the wispy halo of the Sun – the corona –comes into view as the dark disk of the Moon totally obscures the bright Sun. Outside the path of totality, in the Moon’s partial shadow (the penumbra), some portion of the Sun’s bright disk remains visible.

Not all solar eclipses are total. During a partial solar eclipse, only the penumbra touches our planet. The umbra passes either just above the North Pole or just below the South Pole, completely missing the Earth. No total eclipse is visible -- only partial phases can be seen.
A third type of solar eclipse occurs when the Moon's umbra passes across the Earth, but is not quite long enough to touch the surface; the shadow cone diminishes to a point before reaching the Earth. This effect happens when the Moon is farther out in its orbit around the Earth. The Moon appears slightly smaller and is not large enough to completely cover the Sun. When the Moon is centered over the Sun, a ring of sunlight remains visible around the edge. This type of eclipse is called an annular eclipse. (Annular comes from the Latin word meaning "ring.") Because the Sun is not completely covered by the Moon, the rare and dramatic effects of a total solar eclipse (onset of darkness and view of the corona) are not present at either annular or partial eclipses of the Sun. (See Effects During a Total Solar Eclipse.)
Why is a total solar eclipse such a rare event? First of all, eclipses do not occur every month during a new Moon or a full Moon. This is because the orbit of the Moon is tilted by about five degrees with respect to the Earth’s orbit, so that usually the Moon passes slightly above or below the line between the Sun and the Earth. Thus at most new and full Moons, the shadows miss their mark and no eclipse occurs. Only about every six months, during an eclipse season, are the conditions right for a lunar or solar eclipse.