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Escherichia coli (/ ˌ ɛ ʃ ə ˈ r ɪ k i ə ˈ k oʊ l aɪ / ESH-ə-RIK-ee-ə KOH-ly) is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus Escherichia that is commonly found in the lower intestine of warm-blooded organisms. Most E. coli strains are harmless, but some serotypes such as EPEC, and ETEC are pathogenic and can cause serious food poisoning in ...
Google Translate is a web-based free-to-user translation service developed by Google in April 2006. [11] It translates multiple forms of texts and media such as words, phrases and webpages. Originally, Google Translate was released as a statistical machine translation service. [11] The input text had to be translated into English first before ...
The Cambodian genocide[a] was the systematic persecution and killing of Cambodian citizens[b] by the Khmer Rouge under the leadership of Prime Minister of Democratic Kampuchea, Pol Pot. It resulted in the deaths of 1.5 to 2 million people from 1975 to 1979, nearly 25% of Cambodia's population in 1975 (c. 7.8 million).[3][4][5][6][7] Pol Pot ...
Largest economies in the world by GDP (nominal) in 2024 according to International Monetary Fund estimates[n 1][1] Countries by nominal GDP in 2019[n 2] > $20 trillion $10–20 trillion $5–10 trillion $1–5 trillion $750 billion – $1 trillion $500–750 billion $250–500 billion $100–250 billion $50–100 billion $25–50 billion $5 ...
- Etymology
- Occurrence
- Causes
- Interaction of The Solar Wind with Earth
- Auroral Particle Acceleration
- Historically Significant Events
- Historical Views and Folklore
- Extraterrestrial Aurorae
- See Also
- Further Reading
The term aurora borealis was coined by Galileo in 1619, from the Roman Aurora, goddess of the dawn and the Greek name for the north wind (Boreas). The word aurora is derived from the name of the Roman goddess of the dawn, Aurora, who travelled from east to west announcing the coming of the sun. Ancient Greek poets used the corresponding name Eosmet...
Most auroras occur in a band known as the "auroral zone", which is typically 3° to 6° (approximately 330–660 km) wide in latitude and between 10° and 20° from the geomagnetic poles at all local times (or longitudes), most clearly seen at night against a dark sky. A region that currently displays an aurora is called the "auroral oval", a band displa...
A full understanding of the physical processes which lead to different types of auroras is still incomplete, but the basic cause involves the interaction of the solar wind with Earth's magnetosphere. The varying intensity of the solar wind produces effects of different magnitudes but includes one or more of the following physical scenarios. 1. A qu...
Earth is constantly immersed in the solar wind, a flow of magnetized hot plasma (a gas of free electrons and positive ions) emitted by the Sun in all directions, a result of the two-million-degree temperature of the Sun's outermost layer, the corona. The solar wind reaches Earth with a velocity typically around 400 km/s, a density of around 5 ions/...
Just as there are many types of aurora, there are many different mechanisms that accelerate auroral particles into the atmosphere. Electron aurora in Earth's auroral zone (i.e. commonly visible aurora) can be split into two main categories with different immediate causes: diffuse and discrete aurora. Diffuse aurora appear relatively structureless t...
The discovery of a 1770 Japanese diary in 2017 depicting auroras above the ancient Japanese capital of Kyoto suggested that the storm may have been 7% larger than the Carrington event, which affected telegraph networks. The auroras that resulted from the Carrington event on both 28 August and 2 September 1859, are thought to be the most spectacular...
The earliest datable record of an aurora was recorded in the Bamboo Annals, a historical chronicle of the history of ancient China, in 977 or 957 BC.An aurora was described by the Greek explorer Pytheas in the 4th century BC. Seneca wrote about auroras in the first book of his Naturales Quaestiones, classifying them, for instance, as pithaei ('barr...
Both Jupiter and Saturn have magnetic fields that are stronger than Earth's (Jupiter's equatorial field strength is 4.3 gauss, compared to 0.3 gauss for Earth), and both have extensive radiation belts. Auroras have been observed on both gas planets, most clearly using the Hubble Space Telescope, and the Cassini and Galileo spacecraft, as well as on...
Procter, Henry Richardson (1878). "Aurora Polaris" . Encyclopædia Britannica. Vol. III (9th ed.). pp. 90–99.Chree, Charles (1911). "Aurora Polaris" . Encyclopædia Britannica. Vol. 2 (11th ed.). pp. 927–934.These two both include detailed descriptions of historical observations and descriptions.Stern, David P. (1996). "A Brief History of Magnetospheric Physics During the Space Age". Reviews of Geophysics. 34 (1): 1–31. Bibcode:1996RvGeo..34....1S. doi:10.1029/95rg03508.Stern, David P.; Peredo, Mauricio. "The Exploration of the Earth's Magnetosphere". phy6.org.The Organisation for Economic Co-operation and Development (OECD; French: Organisation de coopération et de développement économiques, OCDE) is an intergovernmental organisation with 38 member countries,[1][4] founded in 1961 to stimulate economic progress and world trade. It is a forum whose member countries describe themselves as ...
The Maldives is the smallest country in Asia. Including the sea, the territory spans roughly 90,000 square kilometres (35,000 sq mi), and a land area of 298 square kilometres (115 sq mi). The Maldives is one of the world's most geographically dispersed sovereign states, and the smallest Muslim-majority country by land area.
