英语学习笔记：2017-05-21

dwarf planet

矮行星，冥王星被踢出行星界以后，就成了一颗 dwarf planet

A dwarf planet is a planetary-mass object that is neither a planet nor a natural satellite. That is, it is in direct orbit of the Sun, and is massive enough for its gravity to crush it into a hydrostatic equilibrium shape (usually a spheroid), but has not cleared the neighborhood of other material around its orbit.

Copernicus

哥白尼

Nicolaus Copernicus (/koʊˈpɜːrnɪkəs, kə-/; Polish: Mikołaj Kopernik; German: Nikolaus Kopernikus; Niklas Koppernigk; 19 February 1473 – 24 May 1543) was a Renaissance- and Reformation-era mathematician and astronomer who formulated a model of the universe that placed the Sun rather than the Earth at the center of the universe, likely independently of Aristarchus of Samos, who had formulated such a model some eighteen centuries earlier.

nuclear fusion

核聚变

In nuclear physics, nuclear fusion is a reaction in which two or more atomic nuclei come close enough to form one or more different atomic nuclei and subatomic particles (neutrons or protons). The difference in mass between the products and reactants is manifested as the release of large amounts of energy. This difference in mass arises due to the difference in atomic "binding energy" between the atomic nuclei before and after the reaction. Fusion is the process that powers active or "main sequence" stars, or other high magnitude stars.

corona

日冕

A corona (Latin, 'crown') is an aura of plasma that surrounds the sun and other stars. The Sun's corona extends millions of kilometres into space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph. The word "corona" is a Latin word meaning "crown", from the Ancient Greek κορώνη (korōnè, “garland, wreath”).

Solar and Heliospheric Observatory

太阳和太阳圈探测器

The Solar and Heliospheric Observatory (SOHO) is a spacecraft built by a European industrial consortium led by Matra Marconi Space (now Astrium) that was launched on a Lockheed Martin Atlas II AS launch vehicle on December 2, 1995, to study the Sun, and has discovered over 3000 comets. It began normal operations in May 1996. It is a joint project of international cooperation between the European Space Agency (ESA) and NASA. Originally planned as a two-year mission, SOHO continues to operate after over 20 years in space. In June 2013, a mission extension lasting until December 2016 was approved.

fahrenheit

华氏温标

Fahrenheit is a temperature scale based on one proposed in 1724 by Amsterdam-based physicist Daniel Gabriel Fahrenheit (1686–1736), after whom the scale is named. It uses the degree Fahrenheit (symbol °F) as the unit. Several accounts of how he originally defined his scale exist. The lower defining point, 0 °F, was established as the temperature of a solution of brine made from equal parts of ice and salt. Further limits were established as the melting point of ice (32 °F) and his best estimate of the average human body temperature (96 °F, about 2.6 °F less than the modern value due to a later redefinition of the scale). The scale is now usually defined by two fixed points: the temperature at which water freezes into ice is defined as 32 °F, and the boiling point of water is defined to be 212 °F, a 180 °F separation, as defined at sea level and standard atmospheric pressure.

rubber band

橡皮筋

A rubber band (also known as an elastic or gum band) is a loop of rubber, usually ring shaped, and commonly used to hold multiple objects together. The rubber band was patented in England on March 17, 1845, by Stephen Perry. Most rubber bands are manufactured out of natural rubber, and are sold in a variety of sizes.

Sunspots

太阳黑子

Sunspots are temporary phenomena on the photosphere of the Sun that appear as dark spots compared with surrounding regions. They are areas of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. Sunspots usually appear in pairs of opposite magnetic polarity. Their number varies according to the approximately 11-year solar cycle.