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37-594: The river flows north of the Arctic Circle across a desolate area of Bulunsky District devoid of settlements. The nearest inhabited places are Taymylyr , located downstream from its confluence with the Olenyok, and Sklad (Tyumyati), located a little upstream. In 1875, during his third Siberian expedition, Alexander Chekanovsky intended to "go along the banks of the Lena to the mouth and, if possible, then go to

74-415: A clear night. This happens in both Northern Hemisphere summer solstice and Southern Hemisphere summer solstice . The lowest latitude to experience midnight sun without a golden hour is about 72°34′ North or South. White Nights have become a common symbol of Saint Petersburg, Russia , where they occur from about 11 June to 1 July, and the last 10 days of June are celebrated with cultural events known as

111-513: A low floodplain with marshes and many small lakes. It meanders strongly in stretches until it joins the right bank of the Olenyok river 186 km (116 mi) upstream of its mouth. Owing to the harshness of the climate the river is frozen between early October and early June. The longest tributaries of the Kelimyar are the 51 kilometres (32 mi) long Muoykanda-Yurege and the 44 kilometres (27 mi) long Khotugu-Muoykanda-Yurege from

148-513: A precise moment for the genuine "midnight sun" is required, the observer's longitude , the local civil time , and the equation of time must be taken into account. The moment of the Sun's closest approach to the horizon coincides with its passing due north at the observer's position, which occurs only approximately at midnight in general. Each degree of longitude east of the Greenwich meridian makes

185-524: Is visible at local midnight , and at least once the centre is not visible at local noon . Directly on the Arctic Circle these events occur, in principle, exactly once per year: at the June and December solstices , respectively. However, because of atmospheric refraction and mirages , and also because the sun appears as a disk and not a point, part of the midnight sun is visible, on the night of

222-428: Is no sunset from approximately 19 April to 23 August. The extreme sites are the poles, where the Sun can be continuously visible for half the year. The North Pole has midnight sun for about 6 months, from approximately 18 March to 24 September. South Pole , Antarctica has midnight sun and experiences this from approximately 20 September to 23 March (about 6 months). Due to atmospheric refraction , and also because

259-529: Is seen in the Arctic , the Sun appears to move from left to right. In Antarctica , the equivalent apparent motion is from right to left. This occurs at latitudes ranging from approximately 65°44' to exactly 90° north or south, and does not stop exactly at the Arctic Circle or the Antarctic Circle , due to refraction . The opposite phenomenon, polar night , occurs in winter, when the Sun stays below

296-461: Is the longest day of the year), the Sun will not set. These phenomena are referred to as polar night and midnight sun respectively, and the further north one progresses, the more pronounced these effects become. For example, in the Russian port city of Murmansk , three degrees above the Arctic Circle, the Sun does not rise above the horizon for 40 successive days in midwinter. The position of

333-476: Is visible at the Arctic Circle from approximately 12 June until 1 July. This period extends as one travels north: At Cape Nordkinn, Norway , the northernmost point of Continental Europe , midnight sun lasts approximately from 14 May to 29 July. On the Svalbard archipelago further north, it lasts from 20 April to 22 August. Also, the periods of polar day and polar night are unequal in both polar regions because

370-608: The Arctic Ocean , the Scandinavian Peninsula , North Asia , Northern America , and Greenland. The land within the Arctic Circle is divided among eight countries: Norway, Sweden, Finland, Russia, the United States ( Alaska ), Canada ( Yukon , Northwest Territories , and Nunavut ), Denmark (Greenland), and Iceland (where it passes through the small offshore island of Grímsey ). The climate north of

407-576: The Greek word ἀρκτικός ( arktikos : "near the Bear , northern") and that from the word ἄρκτος ( arktos : " bear "). The Arctic Circle is the southernmost latitude in the Northern Hemisphere at which the centre of the Sun can remain continuously above or below the horizon for twenty-four hours; as a result, at least once each year at any location within the Arctic Circle the centre of the Sun

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444-481: The United States (state of Alaska ). The largest city in the world north of the Arctic Circle, Murmansk , Russia, experiences midnight sun from 22 May to 22 July (62 days). A quarter of Finland's territory lies north of the Arctic Circle, and at the country's northernmost point the Sun does not set at all for 72 days during summer. In Svalbard, Norway , the northernmost inhabited region of Europe, there

481-588: The White Nights Festival . The northernmost tip of Antarctica also experiences white nights near the Southern Hemisphere summer solstice . Since the axial tilt of Earth is considerable (23 degrees, 26 minutes, 21.41196 seconds), at high latitudes the Sun does not set in summer; rather, it remains continuously visible for one day during the summer solstice at the polar circle, for several weeks only 100 km (62 mi) closer to

518-401: The horizon throughout the day. Because there are no permanent human settlements south of the Antarctic Circle , apart from research stations, the countries and territories whose populations experience midnight sun are limited to those crossed by the Arctic Circle : Canada ( Yukon , Nunavut , and Northwest Territories ), Finland , Greenland , Iceland , Norway , Russia , Sweden , and

555-443: The polar circles , in practice, midnight sun can be seen as much as 90 km (56 mi) outside the polar circle, as described below, and the exact latitudes of the furthest reaches of midnight sun depend on topography and vary slightly from year to year. Even though at the Arctic Circle the center of the Sun is, per definition and without refraction by the atmosphere, only visible during one summer night, some part of midnight sun

592-526: The Arctic Circle is generally cold, but the coastal areas of Norway have a generally mild climate as a result of the Gulf Stream , which makes the ports of northern Norway and northwest Russia ice-free all year long. In the interior, summers can be quite warm, while winters are extremely cold. For example, summer temperatures in Norilsk , Russia will sometimes reach as high as 30 °C (86 °F), while

629-589: The Arctic Circle is not fixed and currently runs 66°33′50.2″ north of the Equator . Its latitude depends on the Earth's axial tilt , which fluctuates within a margin of more than 2° over a 41,000-year period, owing to tidal forces resulting from the orbit of the Moon . Consequently, the Arctic Circle is currently drifting northwards at a speed of about 14.5 m (48 ft) per year. The word arctic comes from

666-604: The Arctic Circle with about 5,000 inhabitants. The largest such community in Canada is Inuvik in the Northwest Territories , with 3,137 inhabitants. Download coordinates as: The Arctic Circle is roughly 16,000 km (9,900 mi) in circumference. The area north of the Circle is about 20,000,000 km (7,700,000 sq mi) and covers roughly 4% of Earth's surface. The Arctic Circle passes through

703-466: The Arctic Circle, lying 6 km (4 mi) south of the line. Salekhard (51,186) in Russia is the only city in the world located directly on the Arctic Circle. In contrast, the largest North American community north of the Arctic Circle, Sisimiut ( Greenland ), has approximately 5,600 inhabitants. In the United States, Utqiagvik, Alaska (formerly known as Barrow) is the largest settlement north of

740-625: The Earth is at perihelion in early January and at aphelion in early July. As a result, the polar day is longer than the polar night in the Northern Hemisphere (at Utqiagvik, Alaska , for example, polar day lasts 84 days, while polar night lasts only 68 days), while in the Southern Hemisphere, the situation is the reverse—the polar night is longer than the polar day. Observers at heights appreciably above sea level can experience extended periods of midnight sun as

777-532: The Kelimyar river to the Olenyok. In this way he discovered the roughly 350 kilometres (220 mi) long ridge that bears his name. From the Kelimyar he traced the course of the Olenyok to its mouth. The Kelimyar is a right tributary of the Olenyok. Its sources are in a small lake of the western slopes of the Chekanovsky Ridge . It flows first in a roughly southern direction in its upper course, then it bends northwestwards heading in that direction within

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814-489: The Sun does not rise either, combining effects of midnight sun and polar night, reaching civil twilight during the "day" and astronomical twilight at "night". Locations where the Sun remains less than 6 (or 7 ) degrees below the horizon – between about 60° 34’ (or 59° 34’) latitude and the polar circle – experience midnight twilight instead of midnight sun, so that daytime activities, such as reading, are still possible without artificial light on

851-399: The Sun is a disc rather than a point in the sky, midnight sun may be experienced at latitudes slightly south of the Arctic Circle or north of the Antarctic Circle , though not exceeding one degree (depending on local conditions). For example, Iceland is known for its midnight sun, even though most of it ( Grímsey is the exception) is slightly south of the Arctic Circle. For the same reasons,

888-607: The Sun sets at 12:47   a.m. at the summer solstice. This is because Fairbanks is 51 minutes (1 hour and 51 minutes at Daylight Savings Time) ahead of its idealized time zone (as most of the state is in one time zone) and Alaska observes daylight saving time. (Fairbanks is at about 147.72 degrees west, corresponding to UTC−9 hours 51 minutes, and is on UTC−9 in winter.) This means that solar culmination occurs at about 12:51   p.m. instead of at 12 noon. Also in Fairbanks, Alaska, solar midnight occurs at 01:51 a.m. local time. If

925-454: The most northerly of the five major circles of latitude as shown on maps of Earth at about 66° 34' N. Its southern equivalent is the Antarctic Circle . The Arctic Circle marks the southernmost latitude at which, on the winter solstice (which is the shortest day of the year) in the Northern Hemisphere , the Sun will not rise all day, and on the Northern Hemisphere's summer solstice (which

962-698: The mouth of the Olenyok from the Laptev Sea." From a barge Chekanovsky navigated the Lena River for a distance of about 1,200 kilometres (750 mi) from Yakutsk to the mouth to the Eyekit river, its last major left tributary. He explored inland from the deep and wide lower course of the Eyekit, and then along the rocky and mountainous watershed area lying between the Lena and the Olenyok, descending along

999-411: The northern summer solstice , at a latitude of about 50 minutes of arc (′) (90 km (56 mi)) south of the Arctic Circle. Similarly, on the day of the northern winter solstice , part of the Sun may be seen up to about 50′ north of the Arctic Circle. That is true at sea level ; those limits increase with elevation above sea level , although in mountainous regions there is often no direct view of

1036-458: The only thing different is the equation of time, so this remains a reasonable estimate for a considerable period. The Sun's altitude remains within half a degree of the minimum of about 5 degrees for about 45 minutes either side of this time. When it rotates on its own axis, it sometimes moves closer to the Sun. During this period of Earth's rotation from May to July, Earth tilts at an angle of 23.5 degrees above its own axis in its orbit. This causes

1073-584: The part of Norway located in the Arctic region at the North Pole of Earth to move very close to the Sun and during this time the length of the day increases. It can be said that it almost never subsides. Night falls in Norway's Hammerfest at this particular time of year. The number of days per year with potential midnight sun increases the closer one goes toward either pole . Although approximately defined by

1110-478: The period of sunlight at the poles is slightly longer than six months. Even the northern extremities of the United Kingdom (and places at similar latitudes, such as Saint Petersburg ) experience twilight throughout the night in the northern sky at around the summer solstice. Places sufficiently close to the poles, such as Alert, Nunavut , experience times where it does not get entirely dark at night yet

1147-404: The pole, and for six months at the pole. At extreme latitudes, midnight sun is usually referred to as polar day. At the poles themselves, the Sun rises and sets only once each year on the equinox . During the six months that the Sun is above the horizon, it spends the days appearing to continuously move in circles around the observer, gradually spiralling higher and reaching its highest circuit of

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1184-417: The right, as well as the 70 kilometres (43 mi) long Nyoyokyu , the 66 kilometres (41 mi) long Olongdo, the 39 kilometres (24 mi) long Mene, the 37 kilometres (23 mi) long Amyday, the 36 kilometres (22 mi) long Bulungkaan-Yurege and the 30 kilometres (19 mi) long Kystyk-Khaya-Yurege from the left. Arctic Circle The Arctic Circle is one of the two polar circles , and

1221-526: The sky at the summer solstice. The term "midnight sun" refers to the consecutive 24-hour periods of sunlight experienced north of the Arctic Circle and south of the Antarctic Circle. Other phenomena are sometimes referred to as "midnight sun", but they are caused by time zones and the observance of daylight saving time . For instance, in Fairbanks, Alaska , which is south of the Arctic Circle,

1258-463: The true horizon. The largest communities north of the Arctic Circle are situated in Russia, Norway, and Sweden: Murmansk (population 295,374) and Norilsk (178,018) in Russia; Tromsø (75,638) in Norway, Vorkuta (58,133) in Russia, Bodø (52,357) and Harstad (24,703) in Norway; and Kiruna , Sweden (22,841). Rovaniemi (62,667) in Finland is the largest settlement in the immediate vicinity of

1295-550: The value must be subtracted. As an example, at the North Cape of Norway at midnight on June 21/22, the longitude of 25.9 degrees east makes the moment 103.2 minutes earlier by clock time; but the local time, 2 hours ahead of GMT in the summer, makes it 120 minutes later by clock time. The equation of time at that date is -2.0 minutes. Therefore, the Sun's lowest elevation occurs 120 - 103.2 + 2.0 minutes after midnight: at 00.19 Central European Summer time. On other nearby dates

1332-435: The vital moment exactly 4 minutes earlier than midnight as shown on the clock, while each hour that the local civil time is ahead of coordinated universal time (UTC, also known as GMT) makes the moment an hour later. These two effects must be added. Furthermore, the equation of time (which depends on the date) must be added: a positive value on a given date means that the Sun is running slightly ahead of its average position, so

1369-435: The winter temperatures frequently fall below −50 °C (−58 °F). Starting at the prime meridian and heading eastwards, the Arctic Circle passes through: Midnight sun Midnight sun , also known as polar day , is a natural phenomenon that occurs in the summer months in places north of the Arctic Circle or south of the Antarctic Circle , when the Sun remains visible at the local midnight. When midnight sun

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