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The Weather Forecast Center ( Chinese: 氣象預報中心; pinyin: Qìxiàng Yùbào Zhōngxīn) is the department responsible for monitoring actual weather conditions and making short and medium term forecasts concerning the weather. It also issues severe weather advisories for conditions including heavy rain, cold snaps, typhoons and storms, and dense fog.
Four presidents died in office of natural causes (William Henry Harrison, Zachary Taylor, Warren G. Harding, and Franklin D. Roosevelt), four were assassinated ( Abraham Lincoln, James A. Garfield, William McKinley, and John F. Kennedy ), and one resigned ( Richard Nixon, facing impeachment and removal from office). [9]
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 2020 Atlantic hurricane season was the most active Atlantic hurricane season on record, in terms of number of systems. It featured a total of 31 tropical or subtropical cyclones, with all but one cyclone becoming a named storm. Of the 30 named storms, 14 developed into hurricanes, and a record-tying seven further intensified into major ...
- 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.Mother's Day is an annual holiday celebrated in the United States on the second Sunday in May. Mother's Day recognizes mothers, motherhood and maternal bonds in general, as well as their positive contributions to their families and society.It was established by Anna Jarvis, with the first Mother's Day celebrated through a service of worship at St. Andrew's Methodist Church in Grafton, West ...
Definition The Fourier transform is an analysis process, decomposing a complex-valued function () into its constituent frequencies and their amplitudes. The inverse process is synthesis, which recreates () from its transform.We can start with an analogy, the Fourier series, which analyzes () on a bounded interval [/, /], for some positive real number .
