Solar radiation can be both good and bad for a person's health. When in the light, the human body uses the ultraviolet part of sunlight to make its own Vitamin D. Without sunscreen too much ultraviolet light can cause sunburn and skin cancer. Sun angle makes difference in seasons on Earth as well as in the length of day and night. A high angle makes the tropics hot, and a low angle makes the arctic cold.
Different bodies of the Solar System receive sunlight of different intensities. The table compares the amount of light received by each planet on the Solar System follows:
Solar energy is used in many different ways by people all over the world both in its traditional way for heating, cooking or drying and to make electricity where other power supplies are absent, such as in remote places on Earth or in the space. Sometimes, it is cheaper to make electricity from sunlight than from coal or oil.
Theism
Theism is the religious belief that at least one god exists while rejecting the existence or importance of polytheistic gods or goddesses. In a broader definition it can also be the belief in God or gods in general, including all types of god-belief. Polytheism is the belief in several gods, while monotheism is the belief in just one god. For example, a theistic religion is Christianity. The opposite to a theist is an atheist. An atheist is a person who denies or disbelieves the existence of a supreme being or beings.
All of these are rough definitions of the theisms; they are almost always different. We can split them all into different groups:
Gnosticism and agnosticism can be combined with other forms of theism. For example, it is possible to be an agnostic atheist, or a gnostic theist. In common usage, some people group atheism and agnosticism together under the group of nontheism — absence of clear belief in any deity.
The main types of theism are:
This is another way to group different theisms, based on the nature of the gods.
There are also these types:
Plesiosaur
The plesiosaurs were an order of large, carnivorous marine reptiles. They flourished from 245 million years ago (mya) to 65 mya.
In 1719, William Stukeley described the first partial skeleton of a plesiosaur. The great-grandfather of Charles Darwin, Robert Darwin of Elston told him about it.
Mary Anning was the first to discover a fairly complete plesiosaur. She found it on the 'Jurassic Coast' of Dorset, England in the winter of 1820/21. The fossil was missing its skull, but in 1823 she found another one, this time complete with its skull. The name "Plesiosaurus" was given to it by the Rev. William Conybeare.
The earliest plesiosaur remains are from the Middle Triassic period, and the group was important through the Jurassic and Cretaceous. They had two large pairs of paddles, short tails, short or long necks, and broad bodies. They died out at the K/T extinction event, 65 million years ago.
Plesiosaurs had many bones in their flippers, making them flexible. No modern animal has this four-paddle anatomy: modern turtles use their forelimbs for swimming. They were mainly piscivorous (fish-eaters).
The pliosaurs were a group of mostly large submarine predators with short necks and large heads. Their sizes ranged from two to 15 metres, and they were predators of large fish and other reptiles. Their streamlined body shape suggests they swam and ate under water.
There were three families of long-necked plesiosaurs, who evidently had a different life-style from the pliosaurs. It was suggested by D.M.S. Watson that their method was as surface swimmers, darting down to snatch smaller fish which were feeding on plankton. It is hard to see the benefit of a long neck under water; aquatic mammals operating under water all have a streamlined torpedo-shape, as did pliosaurs and ichthyosaurs. All the longer-necked familiers were, from the setting of the teeth and jaws, eaters of small fish. However, some at least were bottom-feeders, consuming various prey. Digestion of shellfish was aided by gastroliths.
Plesiosaurs have been found with fossils of belemnites (squid-like animals), and ammonites (giant nautilus-like molluscs) associated with their stomachs. But plesiosaurs could not crack shells. Instead, they probably swallowed them whole. In the belly of a plesiosaur were "stomach stones", which are called "gastroliths." These stones moved around in the plesiosaur's stomach and cracked or crushed the shells of the animals it ate. One plesiosaur fossil found in South Dakota had 253 gatroliths weighing a total of 29 pounds.
Live birth has been proved for ichthyosaurs, but is uncertain for plesiosaurs.
Midland, Texas
Midland is a city in the American state of Texas. It is called Midland, because it is the midway point between two bigger cities in Texas, Fort Worth and El Paso. Oil was discovered in the region in 1923 and is still a larger part of the economy.
Midland is also famous as the hometown of former First Lady Barbara Walker Bush. She and her husband, former president George H. W. Bush lived there, with their children including the later US President George W. Bush and his wife Laura, and his brother Jeb Bush, the former Governor of Florida.
Sardinia
Sardinia (, Sardinian: "Sardigna") is the second largest island in the Mediterranean Sea. It is an autonomous region of Italy. It was formerly the Kingdom of Sardinia.
The official name is, in Italian, Regione Autonoma della Sardegna.The capital and largest city is Cagliari.
The island of Sardinia has an area of and, after Sicily, is the second largest island in the Mediterranean Sea. It is long from North to South, and wide from West to East. It lies between 38° 51' and 41° 15' latitude north and 8° 8' and 9° 50' longitude east.
The island is on the western Mediterranean Sea, between the island of Corsica to the north and Tunisia to the south. The Tyrrhenian Sea part of the Mediterranean is directly east of Sardinia, between the Sardinian east coast and the west coast of the Italian mainland peninsula.
The Strait of Bonifacio (, , Gallurese: "Bocchi di Bunifaciu", ) is the strait between Corsica and Sardinia, named after the Corsican town Bonifacio. It is wide and divides the Tyrrhenian Sea from the western Mediterranean Sea.
Sardinia has few major rivers, the largest being the Tirso, long, which flows into the western Mediterranean Sea, the Coghinas () and the Flumendosa ().
The highest peak is Punta La Marmora (), part of the Gennargentu group of mountains in the centre of the island. Other mountain chains are Monte Limbara () in the northeast, the Chain of Marghine and Goceano () running crosswise for towards the north, the Monte Albo (), the Sette Fratelli massif in the southeast, and the Sulcis Mountains and the Monte Linas ().
The mountain chains of the island are separated by wide valleys; the main ones are Campidano in the southwest between Oristano and Cagliari, and the Nurra in the northwest.
There are many small islands around the main island of Sardinia. Some of them are:
Sardinia is divided in eight provinces:
Nuclear reactor
A nuclear reactor is a machine that uses fission to generate heat. There are different designs which use different fuels. Most often, uranium-235 or plutonium-239 are the main components of these fuels.
Most nuclear reactors are used to make electricity. In nuclear power plants heat from the fission reactions in the reactor changes water into steam. The steam is then used to power electric turbines which make electricity. As with other steam engines, the turbines take energy from the movement of the steam.
Some reactors are used for other purposes. Some reactors make neutrons for science research and others make radioactive isotopes. Some universities have small nuclear reactors to teach students how reactors work.