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Astronomical Information for Taunton during December 2021

Starfish imageIntroduction

Welcome to – Astronomical Information from the UK Hydrographic Office

This page provides some astronomical information on a monthly basis for those of you living in the Taunton area. Timings are in GMT (Greenwich Mean Time) unless otherwise noted. Latest additions or updates are highlighted with a red border.

This month we have sections on:


2021 Astronomical and Calendarial Sheet

Download Adobe Acrobat Reader Additional information on the phases of the Moon, the seasons, summer times, eclipses, chronological cycles and eras, religious calendars, the civil calendar and holiday dates in the United Kingdom can be found in HMNAO's Astronomical and Calendarial Sheet No. 108 for 2021. This is a pdf document for which a document reader can be downloaded by clicking on the Adobe Reader icon above.

Remember ...

This web page can also be accessed from outside the UK Hydrographic Office on

↻ The last update to this page was made on Monday, 2021 December 06 at 08:23:38 GMT.

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Starfish imageSolstices & Equinoxes

Solstices and Equinoxes diagram courtesy NASA (357x432) The Winter Solstice for the northern hemisphere (or the Summer Solstice for the southern hemisphere) takes place on Tuesday December 21st at 15:59 GMT. The word 'solstice' comes from the latin for Sun (Sol) and to stand still (sistere) and refers to the fact that the Sun has reached its most extreme declination south in the case of the Winter Solstice for the northern hemisphere. Put another way, the Sun has reached the smallest daily maximum altitude it can attain when due south in the northern hemisphere. For Taunton, at local noon, the Sun reaches a maximum altitude of 15.6° on December 21st.

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Starfish imageThe Sun

  animation of Solar Dynamics Observatory images of the Sun courtesy of NASA An animated view of the Sun's disk over the last twenty eight days is shown in the image on the left. North is at the top of the image and east is to the left. These images come from the Helioseismic and Magnetic Imager instrument on the NASA Solar Dynamics Observatory (SDO) satellite. More multi-wavelength data from the SDO can be found here.

There are three active regions on the visible disk of the Sun. AR2902 lies very close to the north-western limb and has a single small umbral feature. AR2903 lies in the south-western quadrant and has no umbral cores whereas AR2904 lies in the south-eastern quadrant and is composed of two small umbral features. All of these features exhibit simple magnetic fields and pose little threat for significant solar flare activity. At least three coronal mass ejections (CMEs) have been observed over the south-western limb this past weekend of which this one was the brightest. The source of this activity was probably the sunspot complex AR2898–2900 which rotated off the Earth-facing disk of the Sun a few days ago. These CMEs will miss the Earth. The total number of spotless days for 2021 remains at sixty, or 18% of the year so far. Solar winds are currently blowing with velocities of up to 480 km/s and the planetary Kp geomagnetic activity index is likely to peak at 3 (quiet) today. There is a coronal hole approaching the western equatorial limb of the Sun's disk. The Earth currently lies within a stream of solar winds emanating from this feature. The overall amount of solar activity remains at low levels.

NASA reported that a reversal of the Sun's magnetic field took place at the start of 2014 indicating that the maximum of Solar Cycle 24 had been reached. A plot of sunspot numbers, both observed and predicted versus time indicates that the solar maximum of Solar Cycle 24 was more complex than had been previously predicted. The maximum was double-peaked in a similar manner to that of the previous maximum of 2001/2002. The individual peaks occurred in 2011 and 2014 with the latter being the larger of the two. However, sunspot numbers were significantly down on the predictions made for the maximum — indeed Solar Cycle 24 may be the weakest in the last 100 years or so i.e. since Solar Cycle 14.

The declining phase of the solar cycle brings increased numbers of cosmic rays to the Earth, an increased frequency of 'pink' aurorae and a slight dimming of the Sun of approximately 0.1% in terms of the total solar irradiance. TSIS-1 was launched on December 15th 2017; it will monitor the Sun over a five-year period covering the whole of the current solar minimum. Cooling and contraction of the Earth's upper atmosphere in response to the changes on the Sun due to the solar minimum also delayed the orbital decay of satellites such as the Chinese space station, Tiangong 1, which returned to Earth on Monday April 2nd 2018 at 00:16 UTC. The Sun's magnetic field and solar winds provide some protection for the Earth from cosmic rays. A recent paper in the journal Space Weather claims that this solar minimum could see a rise in the number of cosmic rays reaching the Earth by as much as 30% due to the weakening magnetic field of the Sun and reduced levels of solar winds. This could mean an increased risk of radiation exposure for travellers on commercial airlines and possible changes to the climate.

During the post maximum phase of the solar cycle individual energetic events can spawn some of the most powerful flares and coronal mass ejections of the cycle. The so-called Carrington event on September 1st–2nd 1859 during Solar Cycle 10 is a good example of just what might ensue from this type of violent outburst. On 2020 September 15th NASA and NOAA announced that a minimum of the Sun's activity had been reached in December 2019 bringing to an end the old Solar Cycle 24. Initial predictions were that Solar Cycle 25 would be a weak one, similar to its predecessor, peaking in 2025. As a result, it would produce a deep minimum with long periods without much sunspot or flare activity. Space weather would be dominated by solar winds and cosmic rays rather than sunspots and solar flare activity. However, Solar Cycle 25 has produced larger numbers of sunspots relative to the predictions made by the NOAA/NASA Solar Cycle 25 Prediction Panel in 2019. For the past eleven months, the sunspot number has significantly exceeded the official forecast. This may suggest a stronger Solar Cycle 25 than predicted which could peak in late 2024 rather than July 2025.

The latest information on solar activity can be found at and at the Space Weather Prediction Center Space Weather Enthusiasts Dashboard.

If an auroral display is possible or likely, warnings can be received from AuroraWatch UK. More UK-focused geomagnetic data can be found at the British Geological Survey web site.

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Starfish imageThe Moon

The sequence of Moon phases for this month and their designations are shown in the following animation:

Continuous Moon Phase animation
  Moon phases for December 2021 are as follows:
New Moon symbol New Moon Saturday December 4th at 07:43 GMT
Lunation 1224
First Quarter symbol First Quarter Saturday December 11th at 01:35 GMT
Full Moon symbol Full Moon Sunday December 19th at 04:35 GMT
'Moon before Yule'
Last Quarter symbol Last Quarter Monday December 27th at 02:23 GMT

The Moon is at perigee (i.e. nearest to the Earth) on Saturday December 4th at 10:04 GMT when it is 356,794 km from the Earth. It is at apogee (i.e. furthest from the Earth) on Saturday December 18th at 02:15 GMT when it is 406,320 km from the Earth.

The combination of the Moon being close to perigee and the phase of the Moon being either new or full (i.e. the Sun, Earth and Moon are in alignment) as it is around Saturday December 4th and shortly thereafter leads to 'perigean (or proxigean)' spring tides i.e. spring tides with a tidal range slightly larger than those of normal spring tides.

On Friday December 3rd, the Moon occults the planet Mars in the constellation of Libra. This occultation by a very thin waning crescent moon is visible from most of Mongolia, north-eastern China, parts of eastern Russia, Japan, most of Micronesia, northernmost Polynesia and the Hawaiian Islands. This occultation is not visible from the United Kingdom.

On Friday December 31st, the Moon occults the planet Mars in the constellation of Ophiuchus. This occultation by a waning crescent moon is visible from parts of southern Australia, Tasmania, Antarctica, South Georgia Island, the southernmost tip of South America and the Falkland Islands. This occultation is not visible from the United Kingdom.

Please follow the New Moon link above to find out more about our Crescent Moon Watch program which involves making a sighting of the new crescent moon as early as possible after the instant of New Moon each month.

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Starfish imageEclipses

Partial eclipse of the Sun There are four eclipses visible from the Earth during 2021 — two Lunar eclipses (one total and one partial) and two Solar eclipses (one annular and one total). Parts of two of the eclipses are visible from the United Kingdom, namely the partial phase of the annular eclipse of the Sun and some of the partial eclipse of the Moon. The total eclipses of the Sun and Moon are not visible from the United Kingdom.

A total eclipse of the Moon occurred on Wednesday May 26th 2021. It was visible in its entirety from south-westernmost Alaska, the Aleutian Islands, the Hawaiian Islands, Polynesia, the central Pacific Ocean region, New Zealand, Melanesia, Micronesia, central and eastern Australia and parts of Antarctica. Parts of the eclipse were visible from the Americas except north-eastern Canada and eastern parts of South America, Indonesia, the Philippines, Japan, eastern Asia, north-easternmost Russia and the eastern half of the Indian Ocean. The eclipse began at 08:46 UT and ended at 13:51 UT. The Moon entered the umbral shadow at 09:45 UT. Totality began at 11:10 UT and ended at 11:28 UT. The Moon left the umbral shadow at 12:53 UT. The eclipse was not visible from the United Kingdom.

An annular eclipse of the Sun occurred on Thursday June 10th 2021. It was visible as a partial eclipse from the north-eastern part of North America, the Arctic Ocean, most of Greenland, Iceland, northern Europe (including the British Isles), Scandinavia, most of Russia, Mongolia and most of China. The path of annularity began over central Ontario and crossed over north-western Quebec, the southern part of Baffin Island, the north-western part of Greenland, the North Pole (for the only time this century) and the north-eastern part of Siberia. The eclipse began at 08:12 UT and ended at 13:11 UT. The annular phase started at 09:50 UT and ended at 11:33 UT. The maximum duration of annularity of 3m 48s took place at 10:42 UT over the sea between Ellesmere Island and north-western Greenland. From Taunton, the partial eclipse started at 10:04 BST and ended at 12:18 BST. The maximum obscuration occurred high in the south-eastern sky at 11:08 BST when 21.4% of the Sun was obscured.

A deep partial eclipse of the Moon occurred on Friday November 19th 2021. It was visible in its entirety from most of North America except the easternmost parts, Mexico, the eastern and central Pacific Ocean regions and north-eastern parts of Russia. Parts of the eclipse were visible from Scandinavia, the British Isles, Iceland, South and Central America, Australasia, Japan, the Philippines, most of Indonesia, eastern and northern Asia. The eclipse started at 06:00 UT and ended at 12:06 UT. The umbral phase of the eclipse started at 07:18 UT and ended at 10:47 UT. The maximum of the eclipse occurred at 09:03 UT with a magnitude of 0.978. The eclipse was visible in part from the United Kingdom. From Taunton, the partial eclipse started at 06:00 UT and ended at 07:35 UT at moonset. This eclipse is the longest partial eclipse of the 21st century lasting 3 hours and 29 minutes. Indeed, this is the longest partial lunar eclipse since 1440 February 18th and a longer one will not occur until 2669 February 8th.

A total eclipse of the Sun occurred on Saturday December 4th 2021. It was visible as a partial eclipse from Antarctica, the South Atlantic Ocean, the southernmost part of South Africa, the South Indian Ocean, Tasmania and the southernmost part of Australia. The path of totality started approximately 450 km to the east of the Falkland Islands, crossed the Weddell Sea and the Ronne Ice Shelf, Ellsworth Land and ended over the Amundsen Sea, approximately 500 km from the coast of western Antarctica. The eclipse started at 05:29 UT and ended at 09:38 UT. The total phase of the eclipse started at 07:00 UT and ended at 08:07 UT. The maximum duration of totality was 1m 57s at 07:33 UT over the Ronne Ice Shelf in western Antarctica. The eclipse was not visible from the United Kingdom.

Further information on all the eclipses in 2021 can be found on the Eclipses Online web pages. This web site provides information on both solar and lunar eclipses in the period from 1501 CE to 2100 CE. Global circumstances of both solar and lunar eclipses are provided as well as local circumstances of the solar eclipses based on a gazetteer of approximately 1500 locations worldwide. Eclipses for next year, 2022, are also available.

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Starfish imageThe Planets

Planets visible with the naked eye ...

Mercury image

Mercury is too close to the Sun to be observed until the final week of December. It is then low in the south-western evening twilight sky at magnitude −0.7 from approximately Saturday December 25th through to the end of the year. Mercury lies 4° south of Venus on Wednesday December 29th.

Venus image

Venus lies in the south-western evening twilight sky at an elongation from the Sun which decreases during the month from 42° to 13°. It reaches greatest illuminated extent on Friday December 4th. Venus sets around an hour after sunset and fades noticeably from magnitude −4.9 at the start of the month to −4.3 at the end of December. It lies 1.9° north of the waxing crescent moon on Tuesday December 7th and lies 4° north of Mercury on Wednesday December 29th.

Mars image

Mars is visible low in the south-eastern morning twilight sky in the constellation of Libra for the first half of the month. It then spends about ten days in Scorpius and spends the remainder of the month in Ophiuchus rising one to two hours before the Sun. It brightens slightly from magnitude +1.6 at the start of the month to +1.5 at the end of December. Mars lies 0.7° south of the waning crescent moon on Friday December 3rd resulting in an occultation in the Asia/Pacific Ocean region. It lies 5° north of Antares (α Scorpii) on Sunday December 26th. Mars lies 0.9° north of the waning crescent moon on Friday December 31st resulting in another occultation in the Oceania/Antarctic region.

Jupiter image

Jupiter appears in the southern evening twilight sky setting in the mid-evening in the south-western sky. It lies in the north-eastern part of the constellation of Capricornus for the first ten days of December before moving into Aquarius for the remainder of the year. Jupiter fades somewhat from magnitude −2.3 at the start of the month to magnitude −2.1 at the end of December. It lies 4° north of the waxing crescent moon on Thursday December 9th.

Saturn image

Saturn appears in the southern evening twilight sky setting in the early evening in the south-western sky. It lies in the central western part of the constellation of Capricornus throughout December. Saturn remains at magnitude +0.7 for the whole of December. It lies 4° north of the waxing crescent moon on Wednesday December 8th. The north side of the ring plane is exposed with a tilt of 17° with the ring system spanning 36 arcseconds while the planet's disk is just over 16 arcseconds wide.

Planets visible with Binoculars ...

Uranus image

Uranus is visible reasonably high in the southern sky in the mid-evening throughout December, rising two to three hours before sunset and setting three to four hours before sunrise. Uranus is visible most of the night as a blue-green object which remains at magnitude +5.7 throughout December. Uranus lies in the central southern part of the constellation of Aries where it remains for the rest of the year. It lies approximately 5.3° north of the fourth magnitude A9 giant star 87 Ceti (μ Ceti). This planet can also be glimpsed with the naked eye under optimum conditions.

Neptune image

Neptune is visible in the southern sky in the early evening throughout December, rising around midday and setting just before midnight. Neptune is a bluish object which remains at magnitude +7.9 throughout December. It lies in the north-eastern part of the constellation of Aquarius where it remains for the rest of the year. Neptune lies approximately 8.6° to the east of the third magnitude M2.5 red-giant star Hydor (λ Aquarii). It is normally visible with good binoculars under optimum conditions although it can also be difficult to distinguish Neptune from other stellar objects of a similar magnitude.

... & Telescopes!

Pluto image

Pluto rises a couple of hours before midday and sets in the early evening, making it visible for a short interval in the south-western twilight sky in the early evening throughout December for observers using larger telescopes. It lies in the north-eastern part of the constellation of Sagittarius about 11° to the south west of the third magnitude binary pair known as Dabih Major and Dabih Minor (β Capricorni) in mid-December. It lies only 4 arcminutes south of Venus on Saturday December 11th. Strictly speaking, this is a dwarf planet which was demoted from the ranks of the 'bona-fide' planets at the 2006 International Astronomical Union General Assembly in Prague. At magnitude +14.8, you will need a much larger telescope to find this remote member of the Solar System.

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Starfish imageMeteor Showers

Perseid meteors in 2010 The Geminid meteor shower is active from Saturday December 4th to Friday December 17th and reaches a peak of activity on Tuesday December 14th at around 07:00 GMT. At its maximum, the shower exhibits as many as 150 meteors per hour for a day or so either side of the peak. This year, the observation of these bright, medium-speed meteors will be compromised by moonlight as the maximum occurs halfway between first quarter moon on Saturday December 11th and full moon on Sunday December 19th. Geminids hit the atmosphere at about 35km/s, disintegrating at about 80km above the surface of the Earth. Nevertheless, this shower can be rich in fireballs (meteors brighter than the planet Venus) due to the rocky nature of its parent object. The radiant, the point in the sky from which the meteors appear to emanate, lies close to the first magnitude star Castor (α Geminorum) in the constellation of Gemini. Observations are normally best carried out between midnight and sunrise when the radiant is highest in the southern part of the sky. This shower is related to the asteroid or 'rock comet' 3200 Phaethon making it one of only two showers not connected with a comet — the other shower being the Quadrantids which are visible at the beginning of next month.

The Ursids are active in the period December 17th–26th with a maximum on December 22nd. The shower normally exhibits a maximum of 10 meteors per hour although it can be as high as 50 e.g. in 1945 and 1986. A near full moon affects observations of the maximum. The radiant is circumpolar and lies near the star Kochab (β Ursae Minoris). No other regular showers exhibiting significant numbers of meteors are active this month. Further information on these and other meteor showers occurring during 2020 can be found at the International Meteor Organization and their 2021 Meteor Shower Calendar.

Meteors can exhibit a variety of colours when they burn up in the Earth's atmosphere. The colour reflects the chemical composition of the meteor. For instance, a red colouration is indicative of atmospheric nitrogen and oxygen, yellow suggests iron, purple or violet suggests calcium, orange suggests sodium, blue or white suggests magnesium and green suggests nickel. The velocity of the meteor also has an effect on its colour as higher kinetic energies will intensify certain colours. Slow meteors appear to be red or orange whereas faster ones appear to be blue. However, the most commonly-observed colours are yellow, orange and sometimes green.

It is worth noting that bright sporadic meteors and fireballs are possible at any time e.g. the fireball observed over many parts of England and Scotland on Saturday March 3rd 2012 at 21:40 GMT. Larger events, known as bolides, are rarer. Typically, this is a very bright fireball reaching an apparent magnitude of −14 or so, perhaps three times as bright as a full moon. Even rarer are the superbolides, events with apparent magnitudes of −17 or so, around 50 times brighter than the full moon. A recent example of a superbolide was the Chelyabinsk meteor of Friday 15th February 2013 at 03:20 UTC which may have been a 20-metre diameter near-Earth asteroid.

A fireball was seen over a significant fraction of the United Kingdom and northern Europe on Sunday February 28th at 21:54 UT lasting approximately 3.5 seconds. It was estimated to be a magnitude −9 fireball which generated a sonic boom as it fell. Fragments of the object may have impacted the Earth in the area north of Cheltenham in Gloucestershire. Its solar-system point of origin may lie in the asteroid belt between Mars and Jupiter. It has since been reported that at least part of the carbonaceous chondrite fell at a property in Winchcombe in Gloucestershire making it the first UK-based meteorite find in the past 30 years. The significance of this type of dark stony meteorite lies in the fact that its chemistry is similar to that of the early Solar System.

A loud sonic boom was heard at 14:58 UT on Saturday March 20th 2021. It rattled windows and shook homes for about 20 to 30 seconds and was heard over large tracts of Dorset, Devon, Somerset and Jersey. An explosion, an earthquake, thunder and a sonic boom from an RAF aircraft have all been ruled out. The culprit appears to be a daylight fireball or bolide which may have landed in the Bristol Channel. It has been photographed and may also have been detected on a Eumetsat weather satellite image. To be visible in daylight, the meteor must have been of a significant size, large enough for debris to have reached the ground. Its track through the atmosphere may be revealed by analysis of photographic material.

Another loosely-related phenomenon is the re-entry of space debris from space vehicles and satellites whose orbits are decaying to the point where they burn up in the Earth's atmosphere. A couple of well-reported examples of this occurred at around 23:00 BST on Friday September 21st 2012 as well as the return of the GOCE satellite just after midnight on Tuesday November 12th 2013.

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Starfish imageComets

Comet McNaught - January 2007There are a number of comets around the sky at the moment. However, most of them require telescopic assistance to see them and some may be too far south in the sky to be seen by observers based in the United Kingdom. Here is a brief summary of the comets brighter than eleventh magnitude that may be accessible to observers with binoculars or small telescopes in the northern hemisphere.

C/2019 L3 (Atlas) starts the month as a magnitude +9.8 object in the constellation of Lynx where it remains for two weeks before moving into Auriga for three days and then moving into Gemini for the remainder of the month. It should brighten slowly by about 0.2 magnitudes as the month progresses and will be visible with a small telescope reasonably high in the eastern sky around midnight. It will reach perihelion on Sunday January 9th 2022.

67P/Churyumov-Gerasimenko starts the month as a magnitude +8.8 object in the constellation of Cancer where it remains for the whole of December. It should fade by about 0.7 magnitudes as the month progresses and will be visible with binoculars or a small telescope reasonably high in the southern morning pre-twilight sky. On Tuesday November 2nd this comet reached perihelion, passing within 0.4 au of the Earth when it reached a maximum brightness of magnitude +8.5.

The possibility of a naked-eye comet in the run up to Christmas, namely, C/2021 A1 (Leonard) in the second week of December, is still possible, assuming you are at a dark site. As of the start of December, this comet, is a magnitude +6.8 object close to the border of the constellations of Canes Venatici and Coma Berenices which will potentially brighten to 4th magnitude during the first half of December. During the month it moves rapidly across the sky spending 3 days in Canes Venatici, 5 days in Böotes, 2 days in Serpens, 1 day in Hercules, 3 days in Ophiuchus, 1 day in Scutum, 5 days in Sagittarius, 9 days in Microscopium, and 2 days in Pisces Austrinus. If it reaches naked-eye visibility, it could be visible either low in the west north-western sky after sunset or slightly higher in the eastern morning twilight sky in the constellation of Böotes at the end of the first week of December. On December 12th it will be at its closest point to the Earth at a distance of 35 million kilometres. As it heads towards perihelion January 3rd 2022, it will be getting rapidly lower in the sky. In early January, forward scattering of sunlight through the comet's dusty atmosphere could generate an additional surge in brightness to magnitude +1. The same sort of phenomenon was observed for Comet McNaught in 2007, making C/2021 A1 (Leonard) potentially visible in twilight. The catch is that the comet will be too far south to be seen by UK observers!

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Starfish imageInternational Space Station

NASA International Space Station photo If you want to look for the International Space Station (ISS) as it passes over Taunton, please have a look at the predictions page on the Heavens Above web site. The ISS is at least as bright as a first magnitude star and can approach the brightness of Venus under favourable conditions. Similarly, if you want to look for the core module of the new, third generation Chinese space station, Tianhe-1, predictions for this 'under-construction' space station can be found on this page. This module, the first of three parts, was launched on Thursday April 29th 2021. Tianhe-1 is significantly fainter than the ISS, normally about as bright as a third of fourth magnitude star. Predictions for other satellites may also be obtained from the Heavens Above web site.

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Starfish imageAurorae

Ovation auroral prediction for the northern hemisphere The above image is a 30 minute forecast of the location and probability of auroral activity based loosely on a model developed at Johns Hopkins' Applied Physics Laboratory known as the Ovation Aurora Forecast model. It provides estimates of the energy per unit area on the Earth's atmosphere from observations of the solar wind and interplanetary magnetic field made by the Advanced Composition Explorer satellite in conjunction with empirical relationships derived from the Defense Meteorological Satellite Program. It shows where the aurora is most likely to be seen and how bright it might be. The model generates a global estimate of power, called the Hemispheric Power, deposited into the atmosphere in gigawatts (GW). For powers of less than 20GW, little or no aurora may be visible. For powers of 20-50 GW, you may need to be relatively close to the aurora to see it. For values above 50 GW, the aurora should be easily observable, active and mobile. For values above 100 GW, this is considered to be a significant storm where the aurora may be visible from hundreds of miles away. The current prediction is downloaded when you load this page. If you want to download the latest model, simply reload this page or press F5. If you want to see the full-sized map, please click on the above image.

If an auroral display is possible or likely, warnings can be received from AuroraWatch UK. More UK-focused geomagnetic data can be found at the British Geological Survey web site.

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Starfish imageSky chart for mid-December at 22:00 GMT for Taunton

Sky chart for mid-December 2021 from Taunton at 22:00 BST The above sky chart, generated from the web site, shows what the night sky looks like at 22:00 GMT on Thursday December 16th 2021 from Taunton. The night sky will look the same an hour later at 23:00 GMT at the beginning of the month and an hour earlier at 21:00 GMT at the end of the month. Please click on the chart to see a full-sized sky chart image. If you want to generate your own star chart for Taunton for another date and/or time, please follow this link.

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Starfish imageRise/set times (GMT) for the Sun & Moon for Taunton

In December 2021, the amount of daylight (measured from sunrise to sunset) decreases from 8 hours 15 minutes at the start of the month to 7 hours and 54 minutes at the Winter Solstice and then increases to 7 hours 59 minutes at the end of the month. Total daylight (sunrise to sunset) for the month is 248 hours 2 minutes.

start and end times of civil, nautical and astronomical twilights.

December 2021
Date &
Rise/Set timesDay
h mh mh mh mh m
11Sat08:0616:0613:13** **08:00
26Sun08:1516:11** **12:1607:56
** ** No phenomenon on that day
PLEASE NOTE: These times are in Greenwich Mean Time (GMT) except between 01:00 GMT on March 28th and 01:00 GMT on October 31st when the times are in BST (British Summer Time) which is one hour in advance of GMT.

Useful area for table of rise/set times The timings in the table above should be accurate to within 1–2 minutes inside the red circle superimposed on the map shown on the left.

Rising and setting times for the Sun, Moon and planets and times of twilights for other locations can be obtained from HMNAO's Websurf web pages using the Rise, Set and Twilight Times option.

The actual times at which the Sun will just appear, or disappear, will depend on the difference between the altitudes of the observer and the local horizon and the actual refraction, which depends on the meteorological conditions along the light path. Differences of a minute or so from the tabulated times are to be expected.

For the drivers amongst you, the 'Hours of Darkness', as defined in the Road Vehicle Lighting Regulations (1989), start half an hour after sunset and end half an hour before the following sunrise. Headlights should be used during the Hours of Darkness and sidelights in the half hour periods after sunset and before sunrise. These timings can also be obtained from HMNAO's Websurf web pages using the Rise, Set and Twilight Times option.

For the pilots amongst you, night, according to Statutory Instrument 2016 No. 765, The Air Navigation Order 2016, Schedule I (Interpretation), Article 2, means 'the time from half an hour after sunset until half an hour before sunrise (both times inclusive), sunset and sunrise being determined at surface level'. In other words, the night time period starts at the beginning of the Hours of Darkness and finishes at the end of the Hours of Darkness. In the United States, the Federal Aviation Administration (Federal Aviation Regulations, Section 1.1) defines night as the time between the end of evening civil twilight and the beginning of morning civil twilight as published in the American Air Almanac, converted to local time. Sunset to the following sunrise can also be defined as night in the United States as well as one hour after sunset to one hour before sunrise. By the way, flying in a total eclipse of the Sun does not count as night flying!

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Last modified: Monday, 06 December 2021 at 08:23:38 GMT