Task: Question Answering
Input (English): Context: The Southern Hemisphere is the half sphere of Earth which is south of the equator. It contains all or parts of five continents (Antarctica, Australia, about 90% of South America, the southern third of Africa, and several southern islands off the continental mainland of Asia), four oceans (Indian, South Atlantic, Southern, and South Pacific) and most of the Pacific Islands in Oceania. Its surface is 80.9% water, compared with 60.7% water in the case of the Northern Hemisphere, and it contains 32.7% of Earth's land., A day is a unit of time. In common usage, it is either an interval equal to 24 hours or daytime, the consecutive period of time during which the Sun is above the horizon. The period of time during which the Earth completes one rotation with respect to the Sun is called a "solar day". Several definitions of this universal human concept are used according to context, need and convenience. In 1960, the second was redefined in terms of the orbital motion of the Earth, and was designated the SI base unit of time. The unit of measurement "day", redefined in 1960 as 86 400 SI seconds and symbolized "d", is not an SI unit, but is accepted for use with SI. A civil day is usually 86 400 seconds, plus or minus a possible leap second in Coordinated Universal Time (UTC), and occasionally plus or minus an hour in those locations that change from or to daylight saving time. The word "day" may also refer to a day of the week or to a calendar date, as in answer to the question, "On which day?" The life patterns of humans and many other species are related to Earth's solar day and the day-night cycle (see circadian rhythms)., North is a noun, adjective, or adverb indicating direction or geography. North is one of the four cardinal directions or compass points. It is the opposite of south and is perpendicular to east and west., Daylight saving time (DST) or summer time is the practice of advancing clocks during summer months by one hour so that evening daylight lasts an hour longer, while sacrificing normal sunrise times. Typically, regions with summer time adjust clocks forward one hour close to the start of spring and adjust them backward in the autumn to standard time., The second (symbol: s) (abbreviated s or sec) is the base unit of time in the International System of Units (SI). It is qualitatively defined as the "second" division of the hour by sixty, the first division by sixty being the minute. SI definition of second is "the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom". Seconds may be measured using a mechanical, electrical or an atomic clock., A season is a division of the year marked by changes in weather, ecology and hours of daylight. Seasons result from the yearly orbit of the Earth around the Sun and the tilt of the Earth's rotational axis relative to the plane of the orbit. In temperate and polar regions, the seasons are marked by changes in the intensity of sunlight that reaches the Earth's surface, variations of which may cause animals to go into hibernation or to migrate, and plants to be dormant.
During May, June, and July, the northern hemisphere is exposed to more direct sunlight because the hemisphere faces the sun. The same is true of the southern hemisphere in November, December, and January. It is the tilt of the Earth that causes the Sun to be higher in the sky during the summer months which increases the solar flux. However, due to seasonal lag, June, July, and August are the hottest months in the northern hemisphere and December, January, and February are the hottest months in the southern hemisphere., Earth, otherwise known as the world, is the third planet from the Sun and the only object in the Universe known to harbor life. It is the densest planet in the Solar System and the largest of the four terrestrial planets., The Caribbean (or ) is a region that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Sea and the North Atlantic Ocean) and the surrounding coasts. The region is southeast of the Gulf of Mexico and the North American mainland, east of Central America, and north of South America., The winter solstice (or hibernal solstice), also known as midwinter, is an astronomical phenomenon marking the day with the shortest period of daylight and the longest night of the year.
In the Northern Hemisphere this is the December solstice and in the Southern Hemisphere this is the June solstice., A continent is one of several very large landmasses on Earth. Generally identified by convention rather than any strict criteria, up to seven regions are commonly regarded as continents. Ordered from largest in size to smallest, they are: Asia, Africa, North America, South America, Antarctica, Europe, and Australia. In geology, areas of continental crust include regions covered with water., Antlers are extensions of the skull grown by members of the deer family. They are not true bone structures but they usually grow in symmetrical pairs. In most species, only the male grows antlers and the antlers primarily function in sexual selection as attractions to females and as weapons in fights for control of harems. In many temperate zone species, antlers are shed and regrow each year, while horns are permanent., Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals, that collectively form the "calyx" and lie just beneath the corolla. The calyx and the corolla together make up the perianth. When the petals and sepals of a flower are difficult to distinguish, they are collectively called tepals. Examples of plants in which the term "tepal" is appropriate include genera such as "Aloe" and "Tulipa". Conversely, genera such as "Rosa" and "Phaseolus" have well-distinguished sepals and petals. When the undifferentiated tepals resemble petals, they are referred to as "petaloid", as in petaloid monocots, orders of monocots with brightly coloured tepals. Since they include Liliales, an alternative name is lilioid monocots., Africa is the world's second-largest and second-most-populous continent. At about 30.3 million km² (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area and 20.4 % of its total land area. With 1.1 billion people as of 2013, it accounts for about 15% of the world's human population. The continent is surrounded by the Mediterranean Sea to the north, both the Suez Canal and the Red Sea along the Sinai Peninsula to the northeast, the Indian Ocean to the southeast, and the Atlantic Ocean to the west. The continent includes Madagascar and various archipelagos. It contains 54 fully recognized sovereign states (countries), nine territories and two "de facto" independent states with limited or no recognition., The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined as being in the same celestial hemisphere relative to the invariable plane of the solar system as Earth's North pole.
Due to the Earth's axial tilt, winter in the Northern Hemisphere lasts from the December solstice (typically December 21 UTC) to the March Equinox (typically March 20 UTC), while summer lasts from the June solstice (typically June 21 UTC) through to the September equinox (typically September 23 UTC). The dates vary each year due to the difference between the calendar year and the astronomical year., Generally speaking, a calendar year begins on the New Year's Day of the given calendar system and ends on the day before the following New Year's Day, and thus consists of a whole number of days. A calendar year can also start on any other named day of the calendar, and end on the day before this named day in the following year. To reconcile the calendar year with the astronomical cycle (which has a fractional number of days) certain years contain extra days., The Equator usually refers to an imaginary line on the Earth's surface equidistant from the North Pole and South Pole, dividing the Earth into the Northern Hemisphere and Southern Hemisphere. The Equator is about long; some 78.7% lies across water and 21.3% over land., Summer is the hottest of the four temperate seasons, falling between spring and autumn. At the summer solstice, the days are longest and the nights are shortest, with day-length decreasing as the season progresses after the solstice. The date of the beginning of summer varies according to climate, tradition and culture. When it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere, and vice versa., A calendar date is a reference to a particular day represented within a calendar system. The calendar date allows the specific day to be identified. The number of days between two dates may be calculated. For example, "24 2017" is ten days after "14 2017" in the Gregorian calendar. The date of a particular event depends on the observed time zone. For example, the air attack on Pearl Harbor that began at 7:48 a.m. Hawaiian time on December 7, 1941, took place at 3:18 a.m. December 8 in Japan (Japan Standard Time)., The Solar System is the gravitationally bound system comprising the Sun and the objects that orbit it, either directly or indirectly. Of those objects that orbit the Sun directly, the largest eight are the planets, with the remainder being significantly smaller objects, such as dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly, the moons, two are larger than the smallest planet, Mercury., `` Fall '' redirects here . For other uses , see Fall ( disambiguation ) . Autumn , interchangeably known as fall in North America , is one of the four temperate seasons . Autumn marks the transition from summer into winter , in September ( Northern Hemisphere ) or March ( Southern Hemisphere ) , when the arrival of night becomes noticeably earlier and the temperature cools considerably . One of its main features is the shedding of leaves from deciduous trees . Some cultures regard the autumnal equinox as `` mid-autumn '' , while others with a longer temperature lag treat it as the start of autumn . Meteorologists ( and most of the temperate countries in the southern hemisphere ) use a definition based on months , with autumn being September , October and November in the northern hemisphere , and March , April and May in the southern hemisphere . In North America , autumn is usually considered to start with the September equinox and end with the winter solstice ( 21 or 22 December ) . Popular culture in North America associates Labor Day , the first Monday in September , as the end of summer and the start of autumn ; certain summer traditions , such as wearing white , are discouraged after that date . In North America , the wave of color starts in Canada . It then moves into the United States and across the Great Lakes , and continues down into the mountains of the South . Warm days followed by chilly nights provide the catalyst . In traditional East Asian solar term , autumn starts on or around 8 August and ends on or about 7 November . In Ireland , the autumn months according to the national meteorological service , Met Éireann , are September , October and November . However , according to the Irish Calendar , which is based on ancient Gaelic traditions , autumn lasts throughout the months of August , September and October , or possibly a few days later , depending on tradition . In Australia and New Zealand , autumn officially begins on 1 March and ends on 31 May ., The March equinox or Northward equinox is the equinox on the Earth when the Sun appears to leave the southern hemisphere and cross the celestial equator, heading northward as seen from earth. In the Northern Hemisphere the March equinox is known as the vernal equinox, and in the Southern Hemisphere as the autumnal equinox., A week is a time unit equal to seven days. It is the standard time period used for cycles of work days and rest days in most parts of the world, mostly alongside (but not strictly part of) the Gregorian calendar., Winter is the coldest season of the year in polar and temperate climates, between autumn and spring. Winter is caused by the axis of the Earth in that hemisphere being oriented away from the Sun. Different cultures define different dates as the start of winter, and some use a definition based on weather. When it is winter in the Northern Hemisphere, it is summer in the Southern Hemisphere, and vice versa. In many regions, winter is associated with snow and freezing temperatures. The moment of winter solstice is when the sun's elevation with respect to the North or South Pole is at its most negative value (that is, the sun is at its farthest below the horizon as measured from the pole), meaning this day will have the shortest day and the longest night. The earliest sunset and latest sunrise dates outside the polar regions differ from the date of the winter solstice, however, and these depend on latitude, due to the variation in the solar day throughout the year caused by the Earth's elliptical orbit (see earliest and latest sunrise and sunset)., Sunrise or sun up is the instant at which the upper edge of the Sun appears over the horizon in the morning. The term can also refer to the entire process of the Sun crossing the horizon and its accompanying atmospheric effects., South America is a continent located in the western hemisphere, mostly in the southern hemisphere, with a relatively small portion in the northern hemisphere. It is also considered a subcontinent of the Americas, which is the model used in nations that speak Romance languages. The reference to South America instead of other regions (like Latin America or the Southern Cone) has increased in the last decades due to changing geopolitical dynamics (in particular, the rise of Brazil)., North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It can also be considered a northern subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea., The Americas, also collectively called America, encompass the totality of the continents of North America and South America. Together they make up most of Earth's western hemisphere and comprise the "New World". , Deer (singular and plural) are the ruminant mammals forming the family Cervidae. The two main groups are the Cervinae, including the muntjac, the fallow deer and the chital, and the Capreolinae, including the elk, reindeer (caribou), the Western roe deer, and the Eurasian elk (moose). Female reindeer, and male deer of all species (except the Chinese water deer), grow and shed new antlers each year. In this they differ from permanently horned antelope, which are in the same order, Artiodactyla., Antarctica (US English , UK English or ) is Earth's southernmost continent. It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean. At , it is the fifth-largest continent. For comparison, Antarctica is nearly twice the size of Australia. About 98% of Antarctica is covered by ice that averages in thickness, which extends to all but the northernmost reaches of the Antarctic Peninsula., The International System of Units (SI) defines seven units of measure as a basic set from which all other SI units can be derived. The SI base units and their physical quantities are the metre for measurement of length, the kilogram for mass, the second for time, the ampere for electric current, the kelvin for temperature, the candela for luminous intensity, and the mole for amount of substance., Deciduous means "falling off at maturity"
" or "tending to fall off", and it is typically used in order to refer to trees or shrubs that lose their leaves seasonally (most commonly during autumn) and to the shedding of other plant structures such as petals after flowering or fruit when ripe. In a more general sense, "deciduous" means "the dropping of a part that is no longer needed" or "falling away after its purpose is finished". In plants it is the result of natural processes. "Deciduous" has a similar meaning when referring to animal parts, such as deciduous antlers in deer or deciduous teeth, also known as baby teeth, in some mammals (including humans)., The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south and is bounded by Asia and Australia in the west and the Americas in the east., The Western Hemisphere is a geographical term for the half of the earth that lies west of the Prime meridian (which crosses Greenwich, UK) and east of the antimeridian, the other half being called the Eastern Hemisphere. , The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process.<ref name="doi10.1146/annurev-astro-081913-040012"></ref> It is by far the most important source of energy for life on Earth. Its diameter is about 109 times that of Earth, and its mass is about 330,000 times that of Earth, accounting for about 99.86% of the total mass of the Solar System.
About three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron., Snow pertains to frozen crystalline water throughout its life cycle, starting when it precipitates from clouds and accumulates on surfaces, then metamorphoses in place, and ultimately melts, slides or sublimates away. Snowstorms organize and develop by feeding on sources of atmospheric moisture and cold air. Snowflakes nucleate around particles in the atmosphere by attracting supercooled water droplets, which freeze in hexagonal-shaped crystals. Snowflakes take on a variety of shapes, basic among these are platelets, needles, columns and rime. As snow accumulates into a snowpack, it may blow into drifts. Over time, accumulated snow metamorphoses, by sintering, sublimation and freeze-thaw. Where the climate is cold enough for year-to-year accumulation, a glacier may form. Otherwise, snow typically melts, seasonally, and causes runoff into streams and rivers and recharging groundwater., The horizon or skyline is the apparent line that separates earth from sky, the line that divides all visible directions into two categories: those that intersect the Earth's surface, and those that do not. At many locations, the true horizon is obscured by trees, buildings, mountains, etc., and the resulting intersection of earth and sky is called the "visible horizon". When looking at a sea from a shore, the part of the sea closest to the horizon is called the "offing".
The word "horizon" derives from the Greek " " "horizn kyklos", "separating circle", from the verb  "horiz", "to divide", "to separate", and that from "" ("oros"), "boundary, landmark"., In geography, temperate or tepid latitudes of Earth lie between the tropics and the polar regions. The temperatures in these regions are generally relatively moderate, rather than extremely hot or cold, and the changes between summer and winter are also usually moderate., A year is the orbital period of the Earth moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by changes in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the globe, four seasons are generally recognized: "spring", "summer", "autumn" and "winter". In tropical and subtropical regions several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual "wet" and "dry" seasons are recognized and tracked., Australia, officially the Commonwealth of Australia, is a country comprising the mainland of the Australian continent, the island of Tasmania and numerous smaller islands. It is the world's sixth-largest country by total area. The neighbouring countries are Papua New Guinea, Indonesia and East Timor to the north; the Solomon Islands and Vanuatu to the north-east; and New Zealand to the south-east. Australia's capital is Canberra, and its largest urban area is Sydney., The Caribbean Sea is a sea of the Atlantic Ocean in the tropics of the Western Hemisphere. It is bounded by Mexico and Central America to the west and south west, to the north by the Greater Antilles starting with Cuba, to the east by the Lesser Antilles, and to the south by the north coast of South America., Asia is Earth's largest and most populous continent, located primarily in the eastern and northern hemispheres and sharing the continental landmass of Eurasia with the continent of Europe. Asia covers an area of , about 30% of Earth's total land area and 8.7% of the Earth's total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilizations. Asia is notable for not only its overall large size and population, but also dense and large settlements as well as vast barely populated regions within the continent of 4.4 billion people., Night or nighttime ("sp." night-time or night time) is the period of time between the sunset and the sunrise when the Sun is below the horizon., Sunset or sundown, is the daily disappearance of the Sun below the horizon as a result of Earth's rotation.
The Sun will set exactly due west at the equator on the the spring and fall equinoxes, each of which occurs only once a year. 
The time of sunset is defined in astronomy as the moment when the trailing edge of the Sun's disk disappears below the horizon.
Near to the horizon, atmospheric refraction causes the ray path of light from the Sun to be distorted to such an extent that geometrically the Sun's disk is already about one diameter below the horizon when sunset is observed. , The summer solstice (or estival solstice), also known as midsummer, occurs when a planet's rotational axis, in either northern or southern hemispheres, is most inclined toward the star that it orbits. Earth's maximum axial tilt toward the Sun is 23° 26. This happens twice each year (once in each hemisphere), at which times the Sun reaches its highest position in the sky as seen from the north or the south pole., Subject: autumn, Relation: opposite_of, Options: (A) 1 (B) base (C) cycle (D) daylight (E) daytime (F) dwarf (G) east (H) field (I) home (J) lie (K) life (L) morning (M) night (N) north (O) northern hemisphere (P) singular (Q) south (R) southern hemisphere (S) spring (T) standard time (U) sublimation (V) summer (W) sunset (X) true (Y) west (Z) winter
Output (English): spring