Monday, December 25, 2006

Extra-terrestrial weather

Weather phenomena and systems on other planets are consideration to be similar to those on Earth, but often occur on a much bigger scale or involve different substances to those familiar to Earth dwellers. The Cassini-Huygens mission to Titan, for example, discovered clouds produced from methane or ethane which deposit rain composed of liquid methane and other organic compounds.

Extra-terrestrial weather systems can be extremely stable; one of the most famed landmarks in the solar system, Jupiter's Great Red Spot is an anticyclonic storm known to have existed for at least 300 years. On other gas giants, the lack of a surface allows the wind to reach huge speeds: gusts of up to 400 meters per second have been measured on the planet Neptune. This has created a puzzle for planetary scientists: The weather is created by the differential action of the Sun's energy on different places and the amount of energy received by Neptune is very, very small, relative to the Earth, yet the strength and magnitude of weather phenomena on Neptune is far, far greater than on Earth. This mystery is still to be solved.

Monday, December 18, 2006


Music is an art, entertainment, or other human activity that involve organized and audible sounds and silence. It is expressed in terms of pitch, rhythm, harmony, and timbre. Music involves complex generative forms in time through the construction of patterns and combinations of natural stimuli mainly sound. As a human activity, music may be used for artistic or aesthetic, communicative, entertainment, or ceremonial purposes. The definition of what constitutes music varies according to culture and social context.

The broadest definition of music is organized sound. There are observable patterns to what is broadly labeled music, and while there are reasonable cultural variations, the properties of music are the properties of sound as perceived and processed by humans.A more conservative definition would be: Music is harmonious sound created by the playing of instruments as a whole or independently. It is a direct expression of human emotions designed to manipulate and transform the emotion of the listener/listeners. Music is designed to be felt unlike sound which is heard.

Sunday, December 17, 2006


Animals are a main group of organisms, classified as the kingdom Animalia or Meta­zoa. In general they are multi­cellular, capable of locomotion, responsive to their environment, and feed by consuming other organisms. Their body plan becomes permanent as they develop, usually early on in their development as embryos, although some undergo a process of metamorphosis later on.

The word "animal" comes from the Latin word animal, of which animalia is the plural, and is derived from anima, meaning vital breath or soul. In everyday usage animal refers to any member of the animal kingdom that is not a human being, and sometimes excludes insects. The use of the word animal in law classically reflects the common pre-scientific use of the word, roughly equivalent to what modern biology would classify as nonhuman mammal. For example, wildlife laws normally use phrases such as "animals, birds and fish."

Tuesday, December 12, 2006

Hail formation

Hail forms on condensation nuclei such as dust, bugs, or ice crystals, when super cooled water freezes on make contact with. In clouds contains large numbers of super cooled water droplets, these ice nuclei grow quickly at the expense of the liquid droplets because the saturation vapor pressure over ice is slightly less than the saturation vapor pressure over water. If the hail stones grow large enough, latent heat released by further freezing may melt the external shell of the hail stone. The development that follows, usually called wet growth, is more efficient because the liquid outer shell allows the stone to accrete other smaller hail stones in addition to super cooled droplets.

Once a hailstone become too heavy to be supported by the storm's updraft it falls out of the cloud. The reason rain can't fall, is typically because of the tough winds inside a thunderstorm cloud. These winds hold the rain and freeze it. As the process repeats, the hail grows gradually larger. When a hail stone is cut in half, a series of concentric rings, like that of an onion, are revealed. From these rings we can determine the total number of times the hail stone had traveled to the top of the storm before falling to the ground.

Thursday, December 07, 2006

Genetic Engineering

Genetic engineering, genetic modification and gene splicing are terms for the process of manipulating genes, usually outside the organism's normal reproductive process. It involves the isolation, manipulation and reintroduction of DNA into cells or model organisms, usually to express a protein. The aim is to introduce new characteristics or attributes physiologically or physically, such as making a crop resistant to a herbicide, introducing a novel trait, or producing a new protein or enzyme. Examples can include the production of human insulin through the use of modified bacteria, the production of erythropoietin in Chinese Hamster Ovary cells, and the production of new types of experimental mice such as the OncoMouse for research, through genetic redesign.

Since a protein is specified by a segment of DNA called a gene, future versions of that protein can be modified by changing the gene's underlying DNA. One way to do this is to isolate the piece of DNA containing the gene, precisely cut the gene out, and then reintroduce the gene into a different DNA segment. Daniel Nathans and Hamilton Smith received the 1978 Nobel Prize in physiology or medicine for their isolation of restriction endonucleases, which are able to cut DNA at specific sites. Together with ligase, which can join fragments of DNA together, restriction enzymes formed the initial basis of recombinant DNA technology.

Sunday, December 03, 2006

Taj Mahal

The Taj Mahal is a monument located in Agra, India, constructed in 22 years by a workforce of 22,000. The Muslim Mughal Emperor Shah Jahan commissioned its construction as a mausoleum for his favourite wife, Arjumand Bano Begum, who is better known as Mumtaz Mahal.

The Taj Mahal is generally considered the finest example of Mughal architecture, a style that combines elements of Indian, Islamic and Persian architectures. The Taj Mahal has achieved special note because of the romance of its inspiration. While the white domed marble mausoleum is the most familiar part of the monument, the Taj Mahal is actually an integrated complex of structures.

Shah Jahan, who commissioned the monument, was a prolific patron with effectively limitless resources. He had previously created the gardens and palaces of Shalimar in honor of his wife, Mumtaz. After her death in childbirth Shah Jahan was reportedly inconsolable; the court chronicler 'Abd al-Hamid Lahawri tells us that before her death the emperor had but twenty white hairs in his beard, but thereafter many more. The contemporary court chroniclers paid an unusual amount of attention to Mumtaz Mahal's death and Shah Jahan's grief at her demise, and it may well be that the traditional "love-story"