AcharyaChanakya/simple-wikipedia huggingface dataset:
The lower atmosphere is so heated and the pressure so high that helium changes to liquid. It rains down onto the planet. Based on spectroscopy, Jupiter seems to be made of the same gases as Saturn. It is different from Neptune or Uranus. These two planets have much less hydrogen and helium gas.
The very high temperatures and pressures in Jupiter's core mean scientists cannot tell what materials would be there. This cannot be found out, because it is not possible to create the same amount of pressure on Earth.
Above the unknown inner core is an outer core. The outer core of Jupiter is thick, liquid hydrogen. The pressure is high enough to make the hydrogen solid, but then it melts because of the heat.
The planet Jupiter is sometimes called a failed star because it is made of the same elements (hydrogen and helium) as is the Sun, but it is not large enough to have the internal pressure and temperature necessary to cause hydrogen to fuse to helium, the energy source that powers the sun and most other stars.
Jupiter is twice as massive as all the other planets in the Solar System put together. It gives off more heat than it gets from the sun.
Jupiter is 11 times the width of Earth and 318 times as massive. The volume of Jupiter is 1,317 times the volume of Earth. In other words, 1,317 Earth-sized objects could fit inside it.
Jupiter has many bands of clouds going horizontally across its surface. The light parts are zones and the darker are belts. The zones and belts often interact with each other. This causes huge storms. Wind speeds of 360 kilometres per hour (km/h) are common on Jupiter. To show the difference the strongest tropical storms on Earth are about 100 km/h.
Most of the clouds on Jupiter are made of ammonia. There may also be clouds of water vapour like clouds on Earth. Spacecrafts such as Voyager 1 have seen lightning on the surface of the planet. Scientists think it was water vapour because lightning needs water vapour. These lightning bolts have been measured as up 1,000 times as powerful as those on Earth.
The brown and orange colours are caused when sunlight passes through or refracts with the many gases in the atmosphere.
One of the biggest features in Jupiter's atmosphere is the Great Red Spot. It is a huge storm which is bigger than the entire Earth. It is on record since at least 1831, and as early as 1665. Images by the Hubble Space Telescope have shown as many as two smaller "red spots" right next to the Great Red Spot. Storms can last for hours or as long as hundreds of years in the case of the Great Red Spot.
Jupiter has a magnetic field like Earth's but 11 times stronger. It also has a "magnetosphere" much bigger and stronger than Earth's. The field traps radiation belts much stronger than Earth's Van Allen radiation belts, strong enough to endanger any spacecraft travelling past or to Jupiter. The magnetic field is probably caused by the large amounts of liquid metallic hydrogen in the core of Jupiter. The four largest moons of Jupiter and many of the smaller ones orbit or go around the planet within the magnetic field. This protects them from the solar wind. Jupiter's magnetic field is so large, it reaches the orbit of Saturn 7.7 million miles (12 million km) away. The Earth's magnetosphere does not even cover its moon, less than a quarter of a million miles (400,000 km) away.
Jupiter also has a thin planetary ring system. These rings are difficult to see and were not discovered until 1979 by NASA's Voyager 1 probe. There are four parts to Jupiter's rings. The closest ring to Jupiter is called the Halo Ring. The next ring is called the Main Ring. It is about wide and only thick. The Main and Halo rings of Jupiter are made of small, dark particles. The third and fourth rings, called the "Gossamer" Rings, are transparent (see through) and are made from microscopic debris and dust. This dust probably comes from small meteors striking the surface of Jupiter's moons. The third ring is called the Amalthea Gossamer Ring, named after moon Amalthea. The outer ring, the Thebe Gossamer Ring, is named after the moon Thebe. The outer edge of this ring is about from Jupiter.
The orbit of a planet is the time and path it takes to go around the Sun. In the amount of time it takes for Jupiter to orbit the Sun one time, the Earth orbits the Sun 11.86 times. One year on Jupiter is equal to 11.86 years on Earth. The average distance between Jupiter and the Sun is 778 million kilometres. This is five times the distance between Earth and the Sun. Jupiter is not tilted on its axis as much as Earth or Mars. This causes it to have no seasons, for example summer or winter. Jupiter rotates, or spins around very quickly. This causes the planet to bulge in the middle. Jupiter is the fastest spinning planet in the Solar System. It completes one rotation or spin in 10 hours. Because of the bulge, the length of the equator of Jupiter is much longer than the length from pole to pole.
Jupiter is the third brightest object in the night sky, after the Moon and Venus. Because of that, people have always been able to see it from Earth. The first person known to really study the planet was Galileo Galilei in 1610. He was the first person to see Jupiter's moons Io, Europa, Ganymede and Callisto. This was because he used a telescope, unlike anyone before him.
No new moons were discovered for more than two hundred years. In 1892, astronomer E.E Barnard found a new moon using his observatory in California. He called the moon Amalthea. It was the last of Jupiter's 67 moons to be discovered by human observation through a telescope.
In 1994, bits of the comet Shoemaker Levy-9 hit Jupiter. It was the first time people saw a collision between two Solar System objects.
Seven spacecraft have flown past Jupiter since 1973. These were Pioneer 10 (1973), Pioneer 11 (1974), Voyagers 1 and 2 (1979), Ulysses (1992 and 2004), Cassini (2000) and New Horizons (2007).
The Pioneer missions were the first spacecraft to take close up pictures of Jupiter and its moons. Five years later, the two Voyager spacecraft discovered over 20 new moons. They captured photo evidence of lightning on the night side of Jupiter.
The Ulysses probe was sent to study the Sun. It only went to Jupiter after it had finished its main mission. Ulysses had no cameras so it took no photographs.
In 2006, the Cassini spacecraft, on its way to Saturn, took some very good, very clear pictures of the planet. Cassini also found a moon and took a picture of it but it was too far away to show the details.
The Galileo mission in 1995 was the first spacecraft to go into orbit around Jupiter. It flew around the planet for seven years and studied the four biggest moons. It launched a probe into the planet to get information about Jupiter's atmosphere. The probe travelled to a depth of about 150 km before it was crushed by the weight of all the gas above it. This is called pressure. The Galileo spacecraft was also crushed in 2003 when NASA steered the craft into the planet. They did this so that the craft could not crash into Europa, a moon which scientists think might have life.
NASA have sent another spacecraft to Jupiter called Juno. It was launched on August 5, 2011 and arrived at Jupiter on July 4, 2016. NASA published some results from the Juno mission in March 2018. Several other missions have been planned to send spacecraft to Jupiter's moons Europa and Callisto. One called JIMO (Jupiter Icy Moons Orbiter) was cancelled in 2006 because it cost too much money.
Jupiter has 79 known moons. The four largest were seen by Galileo with his primitive telescope, and nine more can be seen from Earth with modern telescopes. The rest of the moons have been identified by spacecraft. The smallest moon (S/2003 J 12) is only one kilometre across. The largest, Ganymede, has a diameter of 5,262 kilometres. It is bigger than the planet Mercury. The other three Galilean moons are Io, Europa and Callisto. Because of the way they orbit Jupiter, gravity affects three of these moons greatly. The friction caused by the gravity of Europa and Ganymede pulling on Io makes it the most volcanic object in the Solar System. It has over 400 volcanoes, more than three times as many as Earth.
Jupiter's large gravity has had an effect on the Solar System. Jupiter protects the inner planets from comets by pulling them towards itself. Because of this, Jupiter has the most comet impacts in the Solar System.
Two groups of asteroids, called Trojan asteroids, have settled into Jupiter's orbit round the Sun. One group is called the "Trojans" and the other group is called the "Greeks". They go around the Sun at the same time as Jupiter.
A king is a man who rules a country, because of inheritance. A king usually comes to power when the previous monarch dies, who is usually a family member of his. Sometimes a person may become king due to the previous monarch's abdication, for example George VI. For most of history, most countries were ruled in this way, especially in Europe. Some countries, such as France, are no longer monarchies. Some, such as the United Kingdom, still have a royal family. In some countries, people chose a new king from other people to decide from.
The wife of a king is called a queen. A woman who becomes a ruler because of inheritance is also called a queen.
If a country has a king or a queen, that means it is a monarchy. A country which a king or queen rules is called a kingdom.
In the Muslim world a King would be known as Malik or Sultan.
Knowledge means the things which are true, as opposed to opinion. Information which is correct is knowledge. Knowledge can always be supported by evidence. If a statement is not supported by evidence, then it is not knowledge. The evidence makes it justified; .
Knowledge can refer to a theoretical or practical understanding of a subject. This was the point of Ryle's distinction between "knowing that" and "knowing how". It can be implicit (as with practical skill or expertise) or explicit (as with the theoretical understanding of a subject); it can be more or less formal or systematic. In philosophy, the study of knowledge is called epistemology. The philosopher Plato defined knowledge as "justified true belief". This definition is the subject of the Gettier problems.
All knowledge is a claim to be true, but the claim can be incorrect. The only claims (propositions) which are certainly true are circular, based on how we use words or terms. We can correctly claim that there are 360 degrees in a circle, since that is part of how circles are defined. The point of Aristotle's syllogism was to show that this kind of reasoning had a machine-like form:
But actually, in the real world, not all swans are white.
The most widely accepted way to find reliable knowledge is the scientific method. Yet one thing all philosophers of science agree is that scientific knowledge is just the best we can do at any one time. All scientific knowledge is provisional, not a claim of absolute truth.
Knowledge in religion is different in that it depends on faith, belief and the authority of religious leaders, not on evidence of a scientific or legal kind. There are differing views on whether religious statements should be regarded as knowledge.
In many expressions of Christianity, such as Catholicism and Anglicanism, knowledge is one of the seven gifts of the Holy Spirit.
In the Garden of Eden knowledge is the factor that made humans greedy and treacherous. But in the Book of Proverbs it states: 'to be wise you must first obey the LORD' (9:10).
In Islam, knowledge has great significance. "The All-Knowing" ("al-ʿAlīm") is one of the Names of God, reflecting distinct properties of God in Islam. The Qur'an asserts that knowledge comes from God () and various "hadith" encourage getting knowledge. Muhammad is reported to have said "Seek knowledge from the cradle to the grave" and "Verily the men of knowledge are the inheritors of the prophets". Islamic scholars, theologians and jurists are often given the title "alim", meaning 'knowledgeable'.
Kauai (Kaua'i in Hawaiian) is the second oldest (after Ni'ihau) and fourth largest of the main Hawaiian Islands, in the United States. Known also as the "Garden Isle", Kaua'i lies 73 miles (117 kilometers) across the Kauai Channel, northwest of Honolulu on Oahu. It is of volcanic origin. The highest point on the island is Kawaikini. It is located above sea level. The wettest spot on Earth, with average rainfall of a year, is just east of Mount Waialeale. The high yearly rainfall has eroded deep valleys and canyons in the central mountain. The waterfalls that have been created by erosion in canyons are now popular tourist spots.
The city of Lihue, on the island's southeast side, is the seat of Kauai County. It has a population of around 6,500, and is the main city on the island. Waimea, which is located on the island's southwest side and the first capital of Kauai, was the first place visited by Englishexplorer Captain James Cook in 1778. It was also the first capital of Kauai. The city is at the head of one of the most beautiful canyons in the world, Waimea Canyon, whose gorge is 900 meters (3,000 feet) deep.
The island of Kauai was featured in Disney's 2002 animated feature film "Lilo & Stitch".
Kahoolawe
Kahoolawe is the smallest of the eight main volcanic islands of Hawaii. It is west of Maui and south of Lanai. It is roughly 11 miles long by across (). The highest point, Lua Makika, is above sea level. The island is dry because its low elevation does not cause much rain (orographic precipitation) to fall from the northeastern trade winds.
Kahoolawe was used as a gunfire and bombing target by the United States military during World War II. It was a defense training area by the United States Navy from around 1941 until May 1994. Popular opinion in the state against this practice brought the end to this use. Navy has since been trying to cleanup unexploded ordnance (bombs and explosive shells) from the island. Ordnance is still buried or lying on the ground. Other items have washed down gullies and still other unexploded ordnance is underwater offshore. In 1981, the entire island was included on the National Register of Historic Places.
The island is planned to be given back to the Hawaiian people. In 1993, the U.S. Congress passed a law that "recognized the cultural importance of the island, required the Navy to return the island to the State, and directed the Navy to do an unexploded ordnance (UXO) cleanup and environmental restoration" . The turnover officially occurred on November 11, 2003, but the cleanup has not yet been completed. The U.S. Navy was given $400 million and 10 years to complete the large cleanup task, but this work has gone much slower than planned.
In 1993, the Hawaii State Legislature established the Kahoolawe Island Reserve. It is made up of the whole island and waters out to from shore. By State Law, Kahoolawe and its waters can only be used for Native Hawaiian cultural, spiritual, and subsistence purposes; fishing; environmental restoration; historic preservation; and education. Commercial uses are not allowed. The Legislature also created the Kahoolawe Island Reserve Commission (KIRC) to manage the Reserve while it is held in trust for a "future Native Hawaiian Sovereignty entity" .
After the cleanup is finished, the restoration of Kahoolawe will need ways to control erosion, restore the plant life, recharge the water table, and slowly replace alien plants with native ones. Plans will include methods for damming gullies and reducing rainwater runoff. Non-natives will temporarily stabilize some areas before the permanent planting of native plants.
Killing a living thing is when someone or something ends that life and makes the living thing die. It means causing a death. When a human being kills another human being, it is called murder or homicide, such as manslaughter.
Pesticides and herbicides are poisons for killing bad wild small animals or plants, respectively.
When a soldier kills another in war, it is called "combat". When the state kills a convict sentenced to capital punishment, it is called execution. When someone kills a powerful person it is called assassination. When a person who wants to die kills himself it is suicide, or euthanasia if killed by another. When people kill other people to eat them, it is called cannibalism.
Kilometre
The kilometre is a common unit used for longer distances on Earth. The international unit for measuring distances is the metre and a kilometre is 1000 metres. It is used in some countries for measuring road and sea distances. In the UK and the USA, the mile is used more than kilometres for road distances and the nautical mile for sea distances.
It is often used to measure the speed of cars, planes and boats by saying how many kilometres it can travel in an hour. This is shown as km/h.
It is also spelled kilometer. This spelling is used in American English.
One kilometre is 0.6214 miles (3280.84 feet). This means that one mile is 1.6093 kilometres.
One kilometre is the approximate distance a healthy adult human being can walk in ten minutes.
Language is the normal way humans communicate. Only humans use language, though other animals communicate through other means. The study of language is called linguistics.
Human language has syntax, a set of rules for connecting words together to make statements and questions. Language can also be changed, by adding new words, for example, to describe new things. Other animals may inherit a set of calls which have pee-set functions.
Language may be done by speech or by writing or by moving the hands to make signs. It follows that language is "not" just any way of communicating. Even some human communication is not language: see non-verbal communication. Humans also use language for thinking.
When people use the word "language", they can also mean:
UNESCO says that 2,500 languages are at risk of becoming extinct.
All languages share certain things which separate them from all other kinds of communication.
There are many more things in common between languages.
The capacity to learn and use language is inherited. Normally, all humans are born with this capability. "Which" language is learned by a child depends on which language is spoken by the child's community. The "capacity" is inherited, but the particular language is learned.
Children have a special period, from about 18 months to about four years, which is critical for learning the language. If this is seriously disrupted, then their language skills will be damaged. Older people learn differently, so they seldom learn a second language as well as they learn their native language.
Mathematics and computer science use created languages called formal languages (like computer programming languages), but these may or may not be 'true' languages. Mathematics itself is seen as a language by many. Some people consider musical notation to be a way of writing the musical language.
Chinese is the language with the most native speakers in the world, but Chinese is not really a language. It is a close family of dialects, some of which are as different as Romance languages are from one another.
English is often called "the international language", or lingua franca. It is the main second language of the world and the international language of science, travel, technology, business, diplomacy, and entertainment. French had a similar status until the 20th century, and other languages had it at other times.
Some languages are made up so that a lot of people around the world can learn them, without the new languages being tied to any specific country or place. These are called constructed languages. One of the most popular of these languages is Esperanto, which is sometimes called "La Internacia Lingvo," or "The International Language." Another of these languages is called Volapük, which was popular about a hundred years ago but is much less popular now. It has mostly been replaced by languages like Esperanto, Interlingua, and Ido. Dialects are basically other versions of a language. For example Hoffish is a dialect of swedish.
Part of the reason that Volapük became unpopular is that some sounds are hard to say for people who speak Spanish or English, two of the most widely spoken languages in the world.
Leisure (or free time) is when a person can choose what to do. During a person's leisure time, they do not have an obligation to be at school or work at a job. During leisure time, people can do fun activities, family activities, or other non-work activity, such as hobbies.
Common forms of recreation or leisure are:
A vacation or holiday is the setting aside of time specifically for leisure. During their vacation, some people travel to a different region or country, and stay at a hotel so that they can do things they could not do near home. Other people prefer to spend their vacation time at home in their own community.
In rich industrialized countries such as the US and Canada, as well as in most European countries, workers are allowed to stay home on the weekend (usually Saturday and Sunday), and use it as leisure time. People in poorer developing countries usually have less leisure time, as they have to work longer hours and more days per year.
Live can be a verb. It rhymes with "give". "To live" means "to be alive" (and not dead). If you live, then you have life.
It can be used in a general way:
Live can be an adjective. It rhymes with "five".
Life is a concept in biology. It is about the characteristics, state, or mode that separates a living thing from dead matter.
The word itself may refer to a living being or to the processes of which living things are a part. It may refer to the period when a living thing is functional (as between birth and death).
The study of life is called biology: people who study life are called biologists. A lifespan is the average length of life in a species. Most life on Earth is powered by solar energy: the only known exceptions are the chemosynthetic bacteria living around the hydrothermal vents on the ocean floor. All life on Earth is based on the chemistry of carbon compounds, specifically involving long-chain molecules such as proteins and nucleic acid. With water, which all life needs, the long molecules are wrapped inside membranes as cells. This may or may not be true of all possible forms of life in the Universe: it is true of all life on Earth today.
Living things, or organisms, can be explained as open systems. They are always changing, because they exchange materials and information with their environment. They undergo metabolism, maintain homeostasis, possess a capacity to grow, respond to stimuli and reproduce.
Through natural selection, they adapt to their environment in successive generations. More complex living organisms can communicate through various means. Many life forms can be found on Earth. The properties common to these organisms—plants, animals, fungi, protists, archaea, and bacteria—are a carbon and water-based cellular form with complex organization and heritable genetic information.
The systems that make up life have many levels of organization. From smallest to biggest, they are: molecule, cell, tissue (group of cells with a common purpose), organ (part of the body with a purpose), organ system (group of organs that work together), organism, population (group of organisms of the same species), community (all of the organisms that interact in an area), ecosystem (all of the organisms in an area and the non-living surroundings), and biosphere (all parts of the Earth that have life).
At present, the Earth is the only planet humans have detailed information about. The question of whether life exists elsewhere in the Universe is open. There have been a number of claims of life elsewhere in the Universe. None of these have been confirmed so far. The best evidence of life outside of Earth is are nucleic acids that have been found in certain types of meteorites.
One explanation of life is called the cell theory. The cell theory has three basic points: all living things are made up of cells. The cell is the smallest living thing that can do all the things needed for life. All cells must come from pre-existing cells.
Something is often said to be alive if it:
However, not all living things fit every point on this list.
They do, however, fit the biochemical definitions: they are made of the same kind of chemicals.
The thermodynamic definition of life is any system which can keep its entropy levels below maximum (usually through adaptation and mutations).
A modern definition was given by Humberto Maturana and Francisco Varela in 1980, to which they gave the name "autopoiesis":
Roth commented that "In short, organisms are self-reproducing and self-maintaining, or 'autopoietic', systems". This approach makes use of molecular biology ideas and systems science ideas.
Life on Earth is made from organic compounds — molecules that contain carbon. Four types of long-chain molecules (macromolecules) are important: carbohydrates, lipids, proteins, and nucleic acids.
Almost all living things need the chemical elements carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus, to build these macromolecules. Living things also need small amounts of other elements, called "trace elements". Water is a very important part of all living things. For example, humans are about two-thirds water. Water is a solvent that lets molecules mix and react with other molecules.
All living things need energy to survive, move, grow, and reproduce. Some can get energy from the environment without help from other living things: these are called producers, or autotrophs. Plants, algae, and some bacteria, a group of producers called photoautotrophs, use the sun's light for energy. When producers use light to make and store organic compounds, this is called photosynthesis. Some other producers, called chemoautotrophs, get energy from chemicals that come out of the ocean floor in hydrothermal vents. Other living things get their energy from organic compounds: these are called consumers, or heterotrophs. Animals, fungi, most bacteria, and most protists are consumers. Consumers can eat other living things or dead material.
Both producers and consumers need to break down organic compounds to free energy. The best way to do this is aerobic respiration, which frees the most energy, but living things can only do aerobic respiration if they have oxygen (O2). They can also break down these compounds without oxygen, using anaerobic respiration or fermentation.
All living things have cells. Every cell has a cell membrane on the outside, and a jelly-like material that fills the inside, called cytoplasm. The membrane is important because it separates the chemicals inside and outside. Some molecules can pass through the membrane, but others cannot. Living cells have genes, made of DNA. Genes say to the cell what to do, like a language. One DNA molecule, with many genes, is called a chromosome. Cells can copy themselves to make two new cells.
There are two main kinds of cells: prokaryotic and eukaryotic. Prokaryotic cells have only a few parts. Their DNA is the shape of a circle, inside the cytoplasm, and they have no membranes inside the cell. Eukaryotic cells are more complex, and they have a cell nucleus. The DNA is inside the nucleus, and a membrane is around the nucleus. Eukaryotic cells also have other parts, called organelles. Some of these other organelles also have membranes.
Taxonomy is how lifeforms are put into groups. The smaller groups are more closely related, but the larger classes are more distantly related. The levels, or ranks, of taxonomy are domain, kingdom, phylum, class, order, family, genus, and species. There are many ideas for the meaning of species. One idea, called the biological species concept, is as follows. A species is a group of living things that can mate with each other, and whose children can make their own children.
Taxonomy aims to group together living things with a common ancestor. This can now be done by comparing their DNA. Originally, it was done by comparing their anatomy.
The three domains of life are Bacteria, Archaea, and Eukarya. Bacteria and archaea are prokaryotic and have only one cell. Bacteria range in size from 0.15 cubic micrometres ("Mycoplasma") to 200,000,000 cubic micrometres ("Thiomargarita namibiensis"). Bacteria have shapes which are useful in classification, such as round, long and thin, and spiral. Some bacteria cause diseases. Bacteria in our intestines are part of our gut flora. They break down some of our food. Both bacteria and archaea may live where larger forms of life cannot. Bacteria have a molecule called peptidoglycan in their cell wall, but archaea do not. Archaea have a molecule called isoprene in their cell membrane, but bacteria do not.
Eukarya are living things with eukaryotic cells, and they can have one cell or many cells. Most eukaryotes use sexual reproduction to make new copies of themselves. In sexual reproduction, two sex cells, one from each parent, join together to make a new living thing.
Plants are eukaryotes that use the Sun's light for energy. They include algae, which live in water, and land plants. All land plants have two forms during their life cycle, called alternation of generations. One form is diploid, where the cells have two copies of their chromosomes, and the other form is haploid, where the cells have one copy of their chromosomes. In land plants, both diploid and haploid forms have many cells. Two kinds of land plants are vascular plants and bryophytes. Vascular plants have long tissues that stretch from end to end of the plant. These tissues carry water and food. Most plants have roots and leaves.
Animals are eukaryotes with many cells, which have no rigid cell walls. All animals are consumers: they survive by eating other organic material. Almost all animals have neurons, a signalling system. They usually have muscles, which make the body move. Many animals have a head and legs. Most animals are either male or female. They need a mate of the opposite sex to make offspring. Sex cells from the male and female can meet inside or outside the body.
Fungi are eukaryotes which may have one cell, like yeasts, or many cells, like mushrooms. They are saprophytes. Fungi break down living or dead material, so they are decomposers. Only fungi, and a few bacteria, can break down lignin and cellulose, two parts of wood. Some fungi are mycorrhiza. They live under ground and give nutrients to plants, like nitrogen and phosphorus. Eukaryotes that are not plants, animals, or fungi are called protists. Most protists live in water.
Over thousands or millions of years, living things can change, through the process of evolution. One kind of evolution is when a species changes over time, such as giraffes growing longer necks. Most of the time, the species because better suited to its environment, a process called adaptation. Evolution can also cause one group of living things to split into two groups. This is called speciation if it makes a new species. An example is mockingbirds on the Galapagos Islands — one species of mockingbird lives on each island, but all the species split from a shared ancestor species. Groups that are bigger than species can also split from a shared ancestor — for example, reptiles and mammals. A group of living things and their shared ancestor is called a clade.
Living things can evolve to be quite different from their ancestors. As a result, parts of the body can also change. The same bone structure became the hands of humans, the hooves of horses, and the wings of birds. Different body parts that evolved from the same thing are called homologous.
Extinction is when all members of a species die. About 99.9% of all species that have ever lived are extinct. Extinction can happen at any time, but it is more common in certain time periods called extinction events. The most recent was 65 million years ago, when the dinosaurs went extinct.
By comparing fossils and DNA, we know that all life on Earth today had a shared ancestor, called the last universal common ancestor (LUCA). Other living things may have been alive at the same time as the LUCA, but they died out. A study from 2018 suggests that the LUCA is about 4.5 billion (4,500,000,000) years old, nearly as old as the Earth. The oldest fossil evidence of life is about 3.5 billion years old.
How did non-living material become alive? This is a difficult question. The first step must have been the creation of organic compounds. In 1953, the Miller–Urey experiment made inorganic compounds into organic compounds, such as amino acids, using heat and energy.
Life needs a source of energy for chemical reactions. On the early Earth, the atmosphere did not have oxygen. Oxidation using the Krebs cycle, which is common today, was not possible. The Krebs cycle may have acted backwards, doing reduction instead of oxidation, and the cycle may have made larger molecules. To make life, molecules needed to make copies of themselves. DNA and RNA make copies of themselves, but only if there is a catalyst — a compound which speeds up the chemical reaction. One guess is that RNA itself served as a catalyst. At some time, the molecules were surrounded by membranes, which made cells.
Law is a set of rules decided by a particular place or authority meant for the purpose of keeping the peace and security of society.
Courts or police may enforce this system of rules and punish people who break the laws, such as by paying a fine, or other penalty including jail. In ancient societies, laws were written by leaders, to set out rules on how people can live, work and do business with each other. But many times in history when laws have been on a false basis to benefit few at the expense of society, they have resulted in conflict. To prevent this, in most countries today, laws are written and voted on by groups of politicians in a legislature, such as a parliament or congress, elected (chosen) by the governed peoples. Countries today have a constitution for the overall framework of society and make further laws as needed for matters of detail. Members of society generally have enough freedom within all the "legal" things they can choose to do. An activity is "illegal" if it breaks a law or does not follow the laws.
A legal code is a written code of laws that are enforced. This may deal with things like police, courts, or punishments. A lawyer, jurist or attorney is a professional who studies and argues the rules of law. In the United States, there are two kinds of attorneys - "transactional" attorneys who write contracts and "litigators" who go to court. In the United Kingdom, these professionals are called solicitors and barristers respectively.
The "Rule of Law" is the law which says that government can only legally use its power in a way the government and the people agree on. It limits the powers a government has, as agreed in a country's constitution. The "Rule of Law" prevents dictatorship and protects the rights of the people. When leaders enforce the legal code honestly, even on themselves and their friends, this is an example of the rule of law being followed. "The rule of law", wrote the ancient Greek philosopher Aristotle in 350 BC, "is better than the rule of any individual."
Culture is usually a major source of the principles behind many laws, and people also tend to trust the ideas based on family and social habits. In many countries throughout history, religion and religious books like the Vedas, Bible or the Koran have been a major source of law.
Civil law is the legal system used in most countries around the world today. Civil law is based on legislation that is found in constitutions or statutes passed by government. The secondary part of civil law is the legal approaches that are part of custom. In civil law governments, judges do not generally have much power, and most of the laws and legal precedent are created by Members of Parliament.
Common law is based on the decisions made by judges in past court cases. It comes from England and it became part of almost every country that once belonged to the British Empire, except Malta, Scotland, the U.S. state of Louisiana, and the Canadian province of Quebec. It is also the predominant form of law in the United States, where many laws called statutes are written by Congress, but many more legal rules exist from the decisions of the courts. Common law had its beginnings in the Middle Ages, when King John was forced by his barons to sign a document called the Magna Carta.
Religious law is law based on religious beliefs or books. Examples include the Jewish Halakha, Islamic Sharia, and Christian Canon law.
Until the 1700s, Sharia law was the main legal system throughout the Muslim world. In some Muslim countries such as Saudi Arabia and Iran, the whole legal systems still base their law on Sharia law. Islamic law is often criticised because it often has harsh penalties for crimes. A serious criticism is the judgement of the European Court that "sharia is incompatible with the fundamental principles of democracy".
The Turkish Refah Party's sharia-based "plurality of legal systems, grounded on religion" was ruled to contravene the European Convention for the Protection of Human Rights and Fundamental Freedoms. The Court decided Refah's plan would "do away with the State's role as the guarantor of individual rights and freedoms" and "infringe the principle of non-discrimination between individuals as regards their enjoyment of public freedoms, which is one of the fundamental principles of democracy".
The history of law is closely connected to the development of human civilizations. Ancient Egyptian law developed in 3000 BC. In 1760 BC King Hammurabi, took ancient Babylonian law and organized it, and had it chiseled in stone for the public to see in the marketplace. These laws became known as the Code of Hammurabi.
The Torah from the Old Testament is an old body of law. It was written around 1280 BC. It has moral rules such as the Ten Commandments, which tell people what things are not permitted. Sometimes people try to change the law. For example, if prostitution is illegal, they try to make it legal.
In democracies, the people in a country usually choose people called politicians to represent them in a legislature. Examples of legislatures include the Houses of Parliament in London, the Congress in Washington, D.C., the Bundestag in Berlin, the Duma in Moscow and the Assemblée nationale in Paris. Most legislatures have two chambers or houses, a 'lower house' and an 'upper house'. To pass legislation, a majority of Members of Parliament must vote for a bill in each house. The legislature is the branch of government that writes laws, and votes on whether they will be approved.
The judiciary is a group of judges who resolve people's disputes and determine whether people who are charged with crimes are guilty. In some jurisdictions the judge does not find guilt or innocence but instead directs a jury, how to interpret facts from a legal perspective, but the jury determines the facts based on evidence presented to them and finds the guilt or innocences of the charged person. Most countries of common law and civil law systems have a system of appeals courts, up to a supreme authority such as the Supreme Court or the High Court. The highest courts usually have the power to remove laws that are unconstitutional (which go against the constitution).
The executive is the governing center of political authority. In most democratic countries, the executive is elected from people who are in the legislature. This group of elected people is called the cabinet. In France, the US and Russia, the executive branch has a President which exists separately from the legislature.
The executive suggests new laws and deals with other countries. As well, the executive usually controls the military, the police, and the bureaucracy. The executive selects ministers, or secretaries of state to control departments such as the health department or the department of justice.
In many jurisdictions the Head of State does not take part in the day-to-day governance of the jurisdiction and takes a largely ceremonial role. This is the case in many Commonwealth nations where the Head of State, usually a Governor almost exclusively acts "on the advice" of the head of the Executive (e.g. the Prime Minister, First Minister or Premier). The primary legal role of the Head of State in these jurisdictions is to act as a check or balance against the Executive, as the Head of State has the rarely exercised power to dissolve the legislature, call elections and dismiss ministers.
The police enforce the criminal laws by arresting people suspected of breaking the law. Bureaucrats are the government workers and government organizations that do work for the government. Bureaucrats work within a system of rules, and they make their decisions in writing.
Lawyers are people who have learned about laws. Lawyers give people advice about their legal rights and duties and represent people in court. To become a lawyer, a person has to complete a two- or three-year university program at a law school and pass an entrance examination. Lawyers work in law firms, for the government, for companies, or by themselves.
Civil society is the people and groups that are not part of government that try to protect people against human rights abuses and try to protect freedom of speech and other individual rights. Organizations that are part of civil society include political parties, debating clubs, trade unions, human rights organizations, newspapers and charities.
"Corporations are among the organizations that use the legal system to further their goals. Like the others, they use means such as campaign donations and advertising to persuade people that they are right. Corporations also engage in commerce and make new things such as automobiles, vaporisers/e-cigarettes, and Unmanned aerial vehicles (i.e. "drones") that the old laws are not well equipped to deal with. Corporations also makes use of a set of rules and regulations to ensure their employees remain loyal to them (usually presented in a legal contract), and that any disobedience towards these rules are considered uncivilized and therefore given grounds for immediate dismissal.
L. L. Zamenhof
Ludwik Lejzer Zamenhof (; , ; – ), credited as L. L. Zamenhof and sometimes as the pseudonymous Dr. Esperanto, was an eye doctor, linguist (who creates a language), and scholar who created the international language Esperanto.
Zamenhof was born in 1859 in the town of Białystok, Poland. At the time, Poland was a part of the Russian Empire. Bialystok contained three major groups: Poles, Belorussians, and Yiddish-speaking Jews. Zamenhof thought that one common language would join these groups and stop fights between them.
His first language was said to be Polish. His parents spoke Russian and Yiddish at home. His father was a German teacher, so Zamenhof learned that language from an early age and spoke the language fluently. Later he learned French, Latin, Greek, Hebrew and English. He also had an interest in Italian, Spanish and Lithuanian.
Zamenhof decided that the international language must have a simple grammar and be easier to learn than Volapük, an earlier international language. He attempted to create the international language with a grammar that was rich, and complex. The basics of Esperanto were published in 1887. He translated the Hebrew Bible into Esperanto.
His grandson, Louis-Christophe Zaleski-Zamenhof, was an engineer.
He was 14 times nominated for the Nobel Peace Prize between 1907 and 1917.
This is a list of sovereign states.
Provinces and territories of Canada
Canada, a country and sovereign state in the northern part of North America, is made up of thirteen administrative divisions: ten provinces and three territories. The different levels of government in Canada are based on the principles of a federation: those of each of the provinces and territories share power with the federal government. The territories' governments have a more limited set of powers versus the federal government than that of the provinces'.
The provinces are in the south of Canada, near the border with the United States. They go from the Atlantic Ocean in the east to the Pacific Ocean in the west. The territories are to the north, where fewer people live, close to the Arctic Circle and Arctic Ocean.
Here is a list of the provinces and territories, and their standard abbreviations, with their capitals (the cities where their governments are based) and largest cities. Canada's national capital, where the federal government meets, is Ottawa.
Las Vegas is a city in the American state of Nevada. There were 640,932 people living in the city in 2015, and more than 2,000,000 people living in the metropolitan area. It is the largest city in Nevada. Las Vegas is also the county seat of Clark County. Carolyn Goodman became the mayor in 2011. Las Vegas and Las Vegans are often stereotypically characterized as fun-loving.
Las Vegas leans to the left. Three of the four congressional districts in Nevada include parts of Las Vegas, and all three congresspeople representing those districts are Democrats from Las Vegas.
Native Americans were the first to reside in the area, specifically the Paiute tribe. It was first called "Las Vegas" (which means "The Meadows" in the Spanish language) by the Spanish. The city is known for its dry weather, as is the rest of southern Nevada. It is surrounded by desert.
The US Army built Fort Baker there in 1864. Las Vegas has natural springs, where people used to stop for water when they were going to Los Angeles or other places in California.
In 1905, 110 acres owned by William A. Clark, on which he built a railroad to Southern California were auctioned and Las Vegas was founded as a railroad town. Las Vegas officially became a city in 1911.
Lanai
Lanai (or Lānaʻi) is sixth largest of the Hawaiian Islands, in the United States. It is also known as the "Pineapple Island". The island is almost a circle in shape and is 18 miles wide in the longest direction. The land area is 140 sq. miles (367 km). It is separated from the island of Moloka'i by the Kalohi Channel to the north.
Lana'i was first seen by Europeans on 25 February 1779 by Captain Clerke, with "HMS Resolution" on the James Cook Pacific Ocean trip. Clerke took command of the ship after Capt. Cook was killed at Kealakekua Bay on February 14, and was leaving the islands for the North Pacific.
In 1922, Jim Dole, the president of Dole Pineapple Company, bought the island of Lana'i. He made a large part of it into the world's largest pineapple plantation.
Tourism on Lana'i started not long ago. That was when the growing of pineapple was slowly coming to an end in the Islands. On Lana'i, you can be with nature and feel the mood of the Hawaiian countryside. Not like nearby O'ahu, the only town (Lana'i City) is small. It has no traffic or shopping centers. Tourists come mainly to relax.
There are three hotels on Lana'i and several golf courses.
A leap year is a year in which an extra day is added to the Gregorian calendar, which is used by most of the world. A common year (an ordinary year) has 365 days, but a leap year has 366 days. The extra day, February 29, is added to the month of February. In an ordinary year, February has 28 days, but in a leap year it has 29 days. The extra day, called a leap day, is the same day of the week as the first day of the month, February 1. Also, in a leap year, the months of January, April, and July all start on the same day of the week.
A leap year comes once every four years. Because of this, a leap year can always be evenly divided by four. For example, 2020 was a leap year. But a year is a common year if it can be evenly divided by 100 but not by 400. This is why 1600, 2000, and 2400 are leap years, but not 1700, 1800, 1900, 2100, 2200, or 2300.
We have leap years because instead of 365 days, the Earth really takes a few minutes less than 365-1/4 days (365.24219) to go completely around the Sun. Without leap years, the seasons would start one day earlier on the calendar every four years. After 360 years, spring in the Northern Hemisphere and autumn in the Southern Hemisphere would begin on December 21 (which is when winter in the Northern Hemisphere and summer in the Southern Hemisphere presently begins).
A number of countries use a lunar calendar (based on the Moon, instead of the Sun, like our solar calendar is). They have leap years when they add an extra lunar month. Different calendars add the extra month in different ways. So a year which has 366 days instead of 365 days where the month of February has 29 days is called a leap year.