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Article Merge[edit]

I think it would be a good idea to merge the summer, winter, and december solstice pages. They pretty much relate to the same thing, and can be efficiently put into one article.

At the very least, the December and Winter solstice articles should be merged, since they are talking about the same subjects, and are supposed to have the exact same information. — Preceding unsigned comment added by HaloEliteLegend (talkcontribs) 01:26, 23 April 2013 (UTC)

WikiProject Time assessment rating comment[edit]

Want to help write or improve articles about Time? Join WikiProject Time or visit the Time Portal for a list of articles that need improving.
Yamara 09:16, 12 February 2008 (UTC)


The Solstice article has the following question inserted before the true beginning of the article: "It has been suggested that Solstice, Summer solstice, Winter solstice, Northern solstice and Southern solstice be merged into this article or section. (Discuss) Proposed since December 2012." and I am answering that question only. That is a very good idea BUT only provided it is done by somebody who has the gift of simple explanation. The current article continues (begins?): "A solstice is an astronomical event that occurs twice each year as the Sun reaches its highest or lowest excursion relative to the celestial equator on the celestial sphere." FGS, for someone who knows nothing about the subject that is NOT simple explanation. From the word "excursion" onwards it is, at first reading, so much gobbledegook. My suggestion is - Let's have a competition to rewrite that opening sentence and then select the winner to produce the first draft of the whole article (elsewhere, leave this article alone until the new one is acceptable and then delete this one). My entry is: "A solstice is an astronomical event that occurs twice each year as the Sun reaches the point in the sky where the shadows it throws of standing objects are either the longest or the shortest." I like the suggestion of using the adjectives 'summer' and 'winter' - it simplifies the whole discussion. I also think that the complete article should discuss the fact that solstice and longest/shortest day are not necessarily the same thing. (talk) 08:47, 30 December 2012 (UTC)

Why is the introduction so all over the place? Why not start with a basic astronomical definition first and then go on about the latin origins etc etc. Something basic like " a Solstice is most commonly defined astronomically in relation to apparent position of the sun in the sky at 2 times during the year at which the earth is the furthest point in its elipse. From an observer on the earth the sun appears to stand still. The solstice is also commonly referred to as either the shortest day or the longest day." Not perfect but something like this. (talk) 07:06, 26 November 2008 (UTC)

I don't believe solstice (or summer solstice or winter solstice) should be capitalized—it's not capitalized in Britannica or Merriam-Webster)—and so I am lowercasing it in this article. — Knowledge Seeker 02:56, 14 Jun 2005 (UTC)

I believe that they would be lower case when used as scientific terms but if they were being used as the direct titles for religious holy-days they should be capitalized. Such editors' conventions have not yet caught up with the times: "The solstice in June is when I join the other Druids at Stonehenge for our Summer Solstice observance." Rejecting that as "wrong" simply perpetuates the prevailing religious chauvanism that leaves us with sentences like "Jesus turned His face to the setting sun while behind Him the moon was already above the earth's eastern horizon." User: Earrach

Proper nouns should be capitalized, and common nouns (such as "solstice") should not. Unfree (talk) 18:47, 22 December 2007 (UTC)

Looks like the angles are messed up in the tropics: should be 23 not 26, and 46 not 43?

Yes, you are correct in believing the correct angles for the tropics of capricorn is 23 and 46. --Wired2Narnia

No, there's only one angle: that between the plane of the ecliptic and that of the equator. Unfree (talk) 18:47, 22 December 2007 (UTC)

Please correct misconceptions[edit]

The orbital diagram is beautiful, but misleading. It suggests that the earth's axis points in a different direction at different seasons of the year. It does not. The earth's axis should be tipped in the same direction for both the summer and winter solstice illustrations. You should then change the direction from which the sunshine comes from -- from the right in one, and from the left in the other -- just as it actually does when the earth shifts position by 180 degrees in its orbit. I'd omit the illustration for the equinoxes entirely. Anything you would draw would suggest that the earth's axis is oriented straight up and down, which is of course not correct. In reality, the sunlight would be streaming perpendicular to the page, which is not possible to draw in a two-dimensional illustration. User:BartBenjamin

It would also probably be better to use the terms "December Solstice" and "June Solstice" instead of "winter" and "summer." That way, it is correct for all hemispheres. That is how the International Planetarium Society solves this dilemma for its members located in both hemispheres. User:BartBenjamin

Adding December and June would be OK, but the traditional names are summer and winter. The illustrations fail to show what the labels are pointing at. They should be more schematic. PatShannon

in the Southern hemisphere the winter solstice falls in June while the summer solstice falls in December. As the solstices are important religous holidays in many Pagan traditions and the way in which they are celebrated depends on wether they mark the longest day or the longest night the important distinction is not which month they are in, but rather which season in the location in which they are celebrated. Babylon Horuv 23:27, 22 October 2006 (UTC) Babylon Horuv

The "heliocentric view of the season" is a misnomer if applied to the images that follow. If you see the Earth from the sun ("heliocentric view") then you cannot see a shadow on it. Roberto Casati. —Preceding unsigned comment added by (talk) 10:49, 27 May 2009 (UTC)


The term "altitude" is used a lot to describe the angle of the sun. It's obvious what it means, but can "altitude" strictly be used to describe an angle rather than a distance? Should we instead refer to inclination above the horizon? TerraGreen 00:14, 7 January 2006 (UTC)

Altitude is routinely used to express the angle above the horizon. See for example the much cited US navy site. However the more formal astronomical term is elevation. Inclination is not normally used for positions but for planes (e.g. between equator and ecliptic). The full apparent location of a heavenly body is given by the combination azimuth and elevation. Although not scientific evidence, a quick search on Google reveals:

  • azimuth elevation: 1.27M hits
  • azimuth altitude: 1.57M hits

Woodstone 14:21, 7 January 2006 (UTC)

Altitude and azimuth go together in astronomy. In surveying, what astronomers call altitude is called elevation. (Both altitude and elevation can be used to refer to a height, in linear measure, above sea level or the surrounding ground level, but that's a different issue; here, we're referring to angular measures.) One can measure the elevation (not altitude) of one thing above another using a sextant, but altitude always refers to an object's elevation above the horizon. Using a theodolite, surveyors determine what they call elevations, but I don't know what they call the difference between two elevations. Since "solstice" is not of much use in surveying, it's the astronomical altitude that we mean here. It's measured perpendicularly to the observer's horizon (considered perpendicular to the direction of the earth's center, regardless of the surrounding landscape), and azimuth is measured along the horizon, from due north, so the celestial north pole has an azimuth of zero, and an altitude equal to the observer's latitude. Unfree (talk) 20:36, 22 December 2007 (UTC)

capitalization of directions[edit]

Directions such as south and north are capitalized in this article. According to the Manual of style , they shouldn't.

solstice definition[edit]

I changed the definition from "the moment the Sun reaches its furthest angular distance to the equator" to "the moment Earth tilts at its greatest distance towards or away from the Sun" because the former conveyed that the sun moves as opposed to Earth's rotational axis tilting. I'm sorry if I this change is incorrect. If I am wrong, please tell me why. Jecowa 07:01, 21 April 2006 (UTC)

"To tilt at" means to attack with a lance. An angular distance is an angle. Earth's greatest distance from the sun is its aphelion, and Sun's apogee. This is whimsy; don't take it seriously -- unless I'm your elder. ;-) Unfree (talk) 21:24, 22 December 2007 (UTC)

Thank you, thank you. IMHO, geocentric coordinate systems have no place in explanations of the "why" of solstices and equinoxes yet they do seem to comprise 98% of the text in the leading paragraphs of dictionary, encyclopaedia and textbook definitions. Your choice of words actually explains what the event is / is caused by. Spherical Astronomy terms simply list the aparrent positions and motions seen from the ground: telling us only about certain effects rather than the "cause". Defining the summer solstice as "the moment when the sun has reached its highest declination above the celestial equator" - "explains" virtually nothing. I would though change your phrasing slightly, hopefully to make it even a little more clear: "Solstices: the moments on opposite sides of our annual orbital path where the Earth's constant 23 degree axial tilt comes directly in line with the Sun." 6_21_06 earrach

Speaking from a complete dummy's perspective, I found your definition (directly above, in your quotes), Earrach the most helpful in getting this concept through my overly thick skull, while sounding at least professional/astronomical (for my own mind, the words I would use, although they are trippy and untechnical are "the moment in the annual orbital path of the Earth when the sun gets the most light "spread across" the Earth). I am going to try to transpose the definition you offered here into the article. Matthew 04:00, 17 February 2007 (UTC)

I'm not sure if "directly in line with the Sun" fully describes the process of the Solstice. Combining the two may help to further add to this defenition. Maybe it should read, "Solstices: the moments on opposite sides of our annual orbital path where the Earth's constant 23 degree axial tilt allows the earth to come in line with the Sun at its furthest declination above or below the celestial equator." —Preceding unsigned comment added by Nthnbtlv4u (talkcontribs) on 6 September 2006

At the time of writing this, the definition (i.e., the first couple sentences) is horribly confusing and generally terrible.Matthew 11:37, 3 June 2007 (UTC)

One would think there would be a standard astronomical definition. Trying to write one ourselves verges on WP:OR, but I might point out the solstices are the moments when the axis of the earth's rotation actually intersects its axis of revolution around the sun. If nothing else, that would be pretty easy to illustrate in a diagram. Glycerinester 09:40, 21 June 2007 (UTC)
While the definition sounds good at first, it does not really hold as the centre of mass of the Solar system, and thus the Earths centre of motion, is not the centre of the Sun. It is approximately the centre of mass of the Sun-Jupiter system, roughly one Solar radius (about 1 s) off the Sun's centre. (talk) 23:29, 19 June 2015 (UTC)

Video Game Disambig[edit]

There is also a video game called Solstice. I was looking for info on it, but got this instead. I decided to add a disambig link to the top of the page. What do you think? GLmathgrant 13:45, 12 May 2006 (UTC)

Good job, GLmathgrant. Jecowa 08:50, 20 June 2006 (UTC)

Illumination of the Earth Images[edit]

In the images shown for the summer and winter solstices the orientation of the Earth's pole shifts from left to right while in actuality the direction of the pole is fixed in at a point near the North Star. Here is an image showing correct views of the Earth at the Jun and Dec solstices but which unfortunately lack some of the astronomical definitions contained in the images shown.

2006 Jun & Dec Solstices.JPG

Animated pictures[edit]

The recently added animated pictures are a bit confusing. The Sun appears to rotate around the Earth. There seems to be a static cloud cover rotating around Earth as well. Animation is nice, but Earth should rotate, the Sun should be still and there should be no falsely repeatedly moving wheather pattern. −Woodstone 20:29, 20 June 2006 (UTC)

Okay, those are both goods ideas. If Earth rotates, then the phase could remain constant which would allow the diagram information to be included as well. Thanks, Jecowa 20:50, 20 June 2006 (UTC)

Pedant alert[edit]

Capitalization of "North/South Pole" is inconsistent in this article. Moreover, 'pole' is here in lowercase, while the North Pole and South Pole articles have it the other way around. It's rarely seen written in lowercase anywhere else, but I'm wary of changing it: Britannica has it capitalised, the OED doesn't. Any suggestions? The article should at least be consistent.

I'm sorry for any inconsistency I've caused. I capitalized North Pole because that's the way it was done in the North Pole article. Jecowa 03:22, 23 June 2006 (UTC)

Tipping vs change of orientation[edit]

The current version of the article states that an Earth's hemisphere tips towards the Sun. That evokes an image of the Earth nodding (in a yearly cycle) towards and away from the Sun. Clearly in a section discussing the Outside View, this is incorrect. The Earth's axis is fixed in space and does not tip. Only its orientation relative to the Sun changes. That was the basis of my preceding edits that were reverted (unjustly).

Secondly "inclination" perhaps even more an official name than obliquity for the angle between two great circles.

Woodstone 17:26, 21 July 2006 (UTC)

It seems to me to be a struggle between two groups of people. Those who understand how it works, and are frustrated if non technical terms are used, because they may not convey the exact meaning. And those who do not know yet know how it works, and get confused by the technical terms, looking for simpler words. I think the explanations should cater for the latter, but the definitions for the former.
Also a lot on confusion seems to come from the question whether the rotation axis keeps its orientation in space or not. I would think the article together with the first two pictures is very clear about that. Or is it? --Tauʻolunga 20:47, 21 July 2006 (UTC)

needs complete rewrite[edit]

Personally I think "outside view" and "inside view" is a bad way to go about it. Firstly, this should be adapted for all change. The axis won't always be tilted at 23.44 degrees and the solstice won't always be on a specific Gregorian calendar month. Secondly, the eccentricity on the earth does have an impact on the Earth's climate, this is probably one of the main reasons for more extreme climate in the south, but it won't always be so due to precession of the equinoxes. The mechanics should be explained better as such. John Riemann Soong 01:58, 25 July 2006 (UTC)

won't always be tilted at 23.44 degrees you have already mentioned by currently makes of about 23.44° (called the "obliquity of the ecliptic") which last link gives full additional information.
solstice won't always be on a specific Gregorian calendar month is (indirectly) mentioned with Refer to the equinox article for some remarks, (and they will remain to happen in June and December for many 1000 years to come).
eccentricity on the earth does have an impact on the Earth's climate, this is probably [citation needed] one of the main reasons for more extreme climate in the south you have already mentioned by adding Due to Milankovitch cycles, what more is needed?
"outside view" and "inside view" is a bad way, no, they give two different viewpoints of the same phenomenon. Only perhaps some better titles can be found.
Briefly, you have already addressed most problems yourself; a complete rewrite seems to me somewhat excessively. --Tauʻolunga 09:11, 25 July 2006 (UTC)
A complete rewrite is completely uncalled for. Minor corrections only. Hmoul 21:43, 29 November 2006 (UTC)

I don't think a complete rewrite would go too far. The article makes a simple idea seem complex. Even the opening sentence is ill-considered: it should be a definition but falls short of the minimal nature of a good definition. Instead of " seen from the North or South Pole" you could (and therefore should) subtitute the weaker " seen from north of the tropic of Cancer or south of the tropic of Capricorn", but even this is far from helpful. The point of the article appears to have been forgotten, with everyone piling in their vaguely-connected facts, adding to the confusion. Mike Shepherd (talk) 09:56, 19 June 2012 (UTC)

Defining moments[edit] added "fact" to "defining moments". I'm not sure what statement he wants a citation for. The Explanatory Supplement to the Astronomical Almanac defines the solstices as the two points on the ecliptic where the ecliptic longitude of the Sun is either 90° or 270° (which is not mentioned in the article). It does not mention the start of the astronomical seasons. — Joe Kress 06:03, 1 September 2006 (UTC)

Table of Solstices[edit]

The table of solstice dates and times appears without any attribution as to its source or, alternatively, an explanation of how it might have been computed. Is tehre a risk that this may have been swiped froma copyright source? 14:21, 10 October 2006 (UTC)

For your reassurance, the table comes from the named reference Earth's Seasons Equinoxes, Solstices, Perihelion, and Aphelion 1992-2020. As a public site by the U.S.A. government, this is free of copyright. And this information was present in the talk page of template:solstice-equinox from the very beginning. −Woodstone 20:22, 10 October 2006 (UTC)
That's gone now, but this exists: Earth's seasons. Unfree (talk) 18:55, 22 December 2007 (UTC)
Also on the U.S. Naval Observatory site is, titled, "Equinoxes, Solstices, Perihelion, and Aphelion, 2000-2020" This seems to draw from the same source data as the one named in the preceding comment. Fredgds (talk) 02:04, 11 December 2009 (UTC)

Since a time expressed in UTC is by definition the time of a event, the equinoxes and solstices can not occur at differing times, as shown in the table. The equinox is defined as the time the Sun appears to cross the Equator.If the Spring equinox occurs at 06:55:12.45 UTC on 21st March then all that is need is a correction for a specific time zone. So that if you refer to Washington DC which is UTC -5 hrs, the equinox actually occurs at 01:55:12.45 Eastern Standard Time. Similarly the Solstice is defined as the moment the Sun appears to actually stop, pause before appearing to move. So that if on the 21st June the Sun reaches its apparent most northerly point in the sky - summer solstice, at 10:45:50.34 UTC, corrections for time difference make the time either earlier - west of the time or later - east of that time. It cannot as the table implies occur at a different time but only at 10:45:50.34 UTC and if you are in Sydney, Australia, then the solstice occurs at 10:45:50.34 UTC which is 10 hours ahead of UTC which means the solstice occurs at 20:45:50.34 local time, in Washington DC it occurs at 05:45:50.34 EST.The Geologist (talk) 16:07, 18 January 2013 (UTC)

The times listed are not for a single event; they are for the two solstices and two equinoxes each year. --Lasunncty (talk) 21:32, 9 February 2013 (UTC)

preferred terms[edit]

I switched the terms from winter/summer and June/December to northern/southern, for reasons that other contributors had already explained in the entry. -gmail "ww0308", not yet a registered wp user, 15 December 2006

switched images[edit]

Also, it appears that someone swapped the images for the heliocentric and geocentric sections! I went ahead and switched them back. -gmail "ww0308", not yet a registered wp user, 15 December 2006

Current Event[edit]

If we are filing this as a current event at the appropriate times, shouldn't we also be noting articles such as "December", "Monday", "day", and "night" as current events? Current event kind of implies that it is something which is expected to happen only once (not true here - this is a cyclical event), and that people, or a limited group of people, will be able to influence in some manner (not true with today's technology). I'm removing the tags. Rhialto 04:18, 21 December 2006 (UTC) ETA: someone beat me to it.

Confusing paragraph[edit]

"The northern solstice is in June on Earth, when the sun is directly over the Tropic of Cancer in the Northern Hemisphere, and the southern solstice is in December,"

I think this should be "The northern summer solstice is in June on Earth, when the sun is directly over the Tropic of Cancer in the Northern Hemisphere, and the southern summer solstice is in December". Agree? —The preceding unsigned comment was added by Craigfis (talkcontribs) 23:11, 21 December 2006 (UTC).

Negative. I feel northern and southern distinctly identify the two and the term summer is ambiguous as already stated in the article.

Why do we use the words, on Earth, here? The months, June and December apply to Earth and only Earth, no other planets in the Solar System have these months, so the months indicate Earthly connections, right?

Instead of using all the passive verbs, why not try to use formal active English? For instance,

"The Earth's northern solstice occurs in June, when the sun is directly over the Tropic of Cancer in the Northern Hemisphere, while the southern soltice occurs in December."

Also, the words northern and southern positively identify Earth, no?

Time Between Solstices[edit]

According to the data the time span between solstices is as follows:

 - 2002-03: 365d 5h 44m
 - 2003-04: 365d 5h 49m
 - 2004-05: 365d 5h 44m
 - 2005-06: 365d 5h 53m
 - 2006-07: 365d 5h 41m
 - 2007-08: 365d 5h 41m
 - 2008-09: 365d 5h 56m

Is this correct? Shouldn't the time from solstice to solstice be the same each year? If not, can somebody explain why in the article.

There are a variety of reasons why the dates of the solstices may change from year to year. It may have something to do with the calender not being exact with regard to astronomical phenomena. For instance, every four years we "correct" this inaccuracy by adding one day to the end of February. There is additional inaccuracy that is corrected over longer periods of time. See Leap year for an explanation. Also, the length of a year increases by a small amount each year. However, this amount is probably too small to be noticable from one year to the next, so I bet it doesn't explain the differences you noted, above. SharkD (talk) 04:30, 13 February 2008 (UTC)
Update: it is also due (in part) to the gravitational attraction of the moon. See here. SharkD (talk) 23:58, 15 February 2008 (UTC)

The table I posted is spans of time NOT dates. The question is not about dates! Leap years have nothing to do with it. If it has to so with the moon's gravity then that info should appear in the article. LogicalOctopus (talk) 23:03, 5 March 2008 (UTC)

This is a good point. LogicalOctopus is correct that leap years have nothing to do with it. Rather, these variations of a few minutes up or down in the intersolstitial year are “due to the nutation, and to the Sun which undergoes planetary perturbations.” Source: J. Meeus and D. Savoie, The History of the Tropical Year (1992), 102 Journal of the British Astronomical Association 40 (click through that link and you can get a pdf copy of the article, it's only a few pages). The issue is discussed at Year#Sidereal, tropical, and anomalistic years and Tropical year#Mean equinox tropical year. —Mathew5000 (talk) 09:14, 26 December 2011 (UTC)

Seemingly a nice article but no references[edit]

This looks like a nice, informative article. Unfortunately, there are no external references given so it is not easy for a reader to verify anything here. Articles should comply with WP:V and WP:RS. I am tagging the article as being completely unreferenced as of this summer solstice. There are also some weasel terms such as "Some consider these terms to be the most neutral and unambiguous." Who is "some"? Statements like this need to be attributed to a particular person or group so that the reader can better evaluate who makes such a claim. I hope that someone knowledgeable about the topic will be able to readily improve upon these areas. Johntex\talk 19:48, 21 June 2007 (UTC)

Solstice a worldwide phenomenon[edit]

"Solstice" refers to a strictly earthly phenomenon, since it refers to the passage of the earth through a point in its orbit, or the point in time at which the passage occurs, which is defined by the extension of the earth's equator into space.

Consider two planes, that of the earth's orbit (the "ecliptic"), and that of the equator (the projection of which onto the celestial sphere is called the "celestial equator"). The passages of Earth through the points in its orbit which coincide with the ecliptic are called equinoxes, and its passages through the points farthest from the ecliptic are called solstices.

It's one thing for most of Earth's population, who live in the northern hemisphere, to call one solstice the "winter" solstice and the other the "summer" one in common parlance, but that's dreadfully provincial. Only "northern" and "southern" make sense worldwide, and this is the World-Wide Web, isn't it? So let's not insult everybody south of the equator by calling the solstice which marks the beginning of summer the "winter" solstice! Unfree (talk) 18:41, 22 December 2007 (UTC)

That is overly protecting. We define the north-moving equinox on other planets as vernal equinox, as a consequence it is also fine to do so for the northern solstice to call it estival solstice. (talk) 23:24, 19 June 2015 (UTC)
Who is "we"? --Lasunncty (talk) 06:55, 20 June 2015 (UTC)

Constellations irrelevant[edit]

"First point of Cancer and first point of Capricorn. One disadvantage of these names is that, due to the precession of the equinoxes, the astrological signs where these solstices are located no longer correspond with the actual constellations."

This reflects the misconception that "Cancer" and "Capricorn" refer to constellations. Actually, they refer to signs of the zodiac, which is of little use in astronomy. But even today, one point in Earth's orbit is called the first point of Aries, referring not to the constellation Aries, but to the first of twelve equal sectors (the "signs") of the zodiac, which is defined by the coincidence of the ecliptic with the equator, and moves in accord with Earth's slowly meandering axis. Unfree (talk) 19:17, 22 December 2007 (UTC)

Actually, the zodiac and the tropical lines are related in exactly this way. They used to point at constellations, hence why these positions are named after constellations. SharkD (talk) 04:12, 13 February 2008 (UTC)

But the tropic lines aren't going to be renamed the sun moves out of those constallations. — Preceding unsigned comment added by (talk) 17:56, 5 March 2012 (UTC)


"The term solstice can also be used in a wider sense, as the date (day) that such a passage happens. The solstices, together with the equinoxes, are connected with the seasons. In some languages they are considered to start or separate the seasons; in others they are considered to be centre points (in English, in the Northern hemisphere, for example, the period around the June solstice is known as midsummer, and Midsummer's Day is 24 June, about three days after the solstice itself)."

I suspect that this peculiarity, that "Midsummer's Day" and "midsummer" refer to the solstice, doesn't reflect general differences among languages, but merely an anomaly in one meaning of one word in one language, and that the idea of seasons beginning at solstices and equinoxes is easily understood and expressible among all languages. The idea of "summer" refers to the warmest quarter of the year in either hemisphere, and its beginning is defined by convention to coincide with a solstice. Regardless of the word "midsummer," this understanding of what "summer" means is as true in England as elsewhere, isn't it? Unfree (talk) 20:04, 22 December 2007 (UTC)

In all East Asian languages (Chinese, Korean, Japanese) the solstices and equinoxes mark the middle of the seasons. In Chinese, of the 24 solar terms, those which describe the beginning of the seasons are lichun, literally meaning begin spring, which occurs when the Sun reaches a celestial longitude of 315° (45° before the northern vernal equinox at 0°); lixia (begin summer) is 45° (45° before 90°); liqiu (begin autumn) is 135° (45° before 180°); and lidong (begin winter) is 225° (45° before 270°). In Korean the corresponding terms are ipchun, ipha, ipchu, and ipdong, whereas in Japanese they are risshun, rikka, risshu, and ritto. — Joe Kress (talk) 23:34, 22 December 2007 (UTC)

Northern-Centric terms[edit]

Can someone actually go through the article and remove the Northern Hemisphere bias from the article? It's currently stating Christmas happens on the winter solstice, which is incorrect for half the world. I have changed the cultural piece to reflect a December and a June solstice because that is more descriptive and accurate. —Preceding unsigned comment added by (talk) 05:27, 23 December 2007 (UTC)

Image:Earth-lighting-winter-solstice EN.png[edit]

First of all I'd like to say that this image is really great! It would be nice, however, to have the images used to map the surface of the Earth correspond to the date (winter solstice) depicted in the diagram. I checked the links to the images used. The "Earth's City Lights" image [1] appears to have been taken on 2000-10-23. The "The Blue Marble: Land Surface, Ocean Color and Sea Ice" image [2] corresponds to 2002-02-08. Having images for the correct date allows one to show how ice and snow patterns are affected by the amount of sunlight reaching the Earth's surface. One could create a matching image for the summer solstice showing growth of the ice packs in Antarctic regions. This would allow the diagram to be reused in other articles that deal more specifically with seasonal changes in climate. Unfortunately, I don't think images for each day of the year exist, and I suppose October and February are pretty close. SharkD (talk) 04:12, 13 February 2008 (UTC)

Some sections of this article must be placed in an external article[edit]

"Heliocentric view of the seasons" and "Geocentric view of the seasons" must be placed in an external article. The reason is both sections are in Solstice and Equinox articles, and corrections in one are not synchronized with the other. —Preceding unsigned comment added by Cablop (talkcontribs) 14:09, 16 February 2008 (UTC)

I took out the section "Geocentric view of the seasons" and put it in a new article Geocentric view of the seasons. [3] It's all unsourced and aside from that has a bunch of problems, the diagrams are too small to see properly. In any event it's too general (i.e. it covers more than just solstices) and so doesn't belong in the Solstice article. As for the other section, "Heliocentric view of the seasons", I'm not sure, it wouldn't hurt to remove that one too. Mathew5000 (talk) 05:34, 25 December 2011 (UTC)


[4] "All places on Earth in... the tropics... will see the Sun in the zenith at least two days per year" - more like exactly two days amirite? (talk) 18:13, 20 June 2008 (UTC)

Dude. look at an analemma. If you stand on the line of the tropic, you should only see the sun at zenith ONE day a year. ( I have stood on the tropic of cancer, but not on the solstice. Anyone stand on the tropic of capricorn? ). The graphic on the analemma page confirms that for the tropical lines, its only one day. go figure....-- (talk) 19:31, 20 June 2008 (UTC)
Actually, at any location between the tropics it is unlikely that you would ever see the Sun exactly in the Zenith, because that would only happen if the Sun passes that latitude at noon. So normally one day, the Sun would pass just south of the zenith, the next day just north. So there are just two chances per year to see it in the zenith. Accordingly, at a location exactly on a tropic, you would only see the Sun in the zenith if the solstice happens to be exactly at noon (true solar time). −Woodstone (talk) 19:54, 20 June 2008 (UTC)

I think that in theory, if you disregard time-zones, and define noon simply as the highest point of the sun during the day where it crosses the given longitude, then there would be at least one point on each and every latitude that sees the sun exactly at the Zenith twice during the year. Imagine that the sun carves a path on the Earth as it moves between the Tropics. This path is defined as the point where the sun is directly overhead, and thus it is noon there. Clearly, as the earth spins and revolves around the sun, there is a path that looks like a helix (except that it is carved on a sphere not a cylinder).

So there has to be SOME point at any given time on the earth between the tropics where it is noon, and the sun is exactly overhead. —Preceding unsigned comment added by (talk) 05:28, 21 June 2008 (UTC)

I have reworded that paragraph. Hopefully this will relieve the confusion. --Lasunncty (talk) 20:08, 1 July 2008 (UTC)

There wasn't any confusion, there was a factual error. No point anywhere on earth, on the tropic, betweeen the tropics, anywhere else, can possibly have the sun at the zenith more than twice per year. Thanks to everyone who participated. -- (talk) 22:11, 1 July 2008 (UTC)

Um, there is one more thing we're forgetting, and, I don't know, this is almost not worth bringing up, but it's true -- the Sun is not a point in our sky, it subtends a disk of about half a degree diameter. If the preceding discussion refers to the center of that disk, then, fine. But very near either tropic on Earth (even a tiny bit OUTSIDE the tropics!), some part of the Sun's disk will be exactly overhead at local solar noon for several days in a row. Fredgds (talk) 03:00, 11 December 2009 (UTC)

June 21st[edit]

That's the "longest day"! -- [5] Bold text —Preceding unsigned comment added by (talk) 18:20, 31 August 2008 (UTC)

New leading tags[edit]

Hello buddy. This is botteville typing from another system. The previous introduction said nothing and was in error. Moreover, it gave a false etymology for solstice. I'm trying to help, here. The article does not even get into modern definitions until far down in the article. Now, here is what I propose. I started by saying there are many ways to define "solstice." You don't like the historical method? Why don't you work one up, or do you do anything else except put tags on? YOU write an introduction according to the method YOU think is appropriate! I am going to finish the section I was on and then stop work! I will be watching what YOU do, and I will give you every benefit of the doubt. I do insist you get it right, whatever you do. The rest of you who are interested now will have a chance to vote. Do you want to fix this article? Now is your chance. If anyone thinks these tags are out of place, take them off. If I see them off I will resume working on the article, unless they are off because someone wrote an adequate intro. By the way, there is nothing wrong with the length of the intro. As for relativity, it does NOT stray from the topic. The sun does not have an "apparent" motion it has a relative motion. Many sources say that. So give it a shot, pick up the thread, do better than me, be aggressive, improve the article. Now is your chance. Let us see how it stands later down the road. My guess is it will not stand anywhere except where it is now, so surprise me! (talk) 17:28, 27 October 2008 (UTC)

First of all, YOU (as you are writing it) should assume good faith, something that you are hardly doing. Your post seems to assume good faith in a superficial way, but it's quite clear that you don't. When I posted those tags, I wasn't attacking your person. I put up the tags to point out a problem with the article, while, in the mean time, I try to devise a solution, i.e. a rewrite. I'm surprised that you're not in favor of this method. The alternative is to be bold and just change everything. Would you prefer that? If so I'd be happy to just delete the entire intro right now and start typing away. Instead, though, I chose the less aggressive and more open method of, first, placing tags up, and, second, changing text. This allows for productive and open discussion on the topic. Unfortunately, you're discussion is not what I had in mind. You are simply being defensive and over-protective. You're call for discussion and inclusion seems more like a defensive come-on -- you don't actually expect or want anyone to weigh in or change anything. But, alas, this is Wikipedia. Whatever you write, you must presume that it will be scrutinized and rewritten mercilessly.
Now, regarding the meat of the problem, first, the intro wouldn't be too long if it was more concise and didn't venture off the path. But, because it does, it's appears too long and meandering. If it wasn't -- if all five paragraphs of the lede contained essential facts and didn't veer off topic -- then, perhaps, a five paragraph intro wouldn't be too long. But I don't think that's the case here.
Second, while, yes, there are certain off topics (like Special Relativity) that must be explained in order for the reader to understand the concept of the solstice, those off topics need not be expounded upon in the intro in as much detail as they are now.
Third, while the current first sentence of the article would be a fine way to start an essay, this isn't any old essay; it's an encyclopedia entry. And, as such, the first sentence (and the first paragraph) should define the topic in a more traditional and easy-to-swallow way. Forget the literary flourishes. I know it sounds terrible, but that's the way Wikipedia is. It's about writing encyclopedia entries, which are often dry, not about writing pretty-sounding or uniquely-worded essays. The current first sentence, for example, doesn't really give the reader a full understanding of the solstice, in so much as one sentence can do. If you look at the featured articles, they all have certain things in common. One of those things is a strong, complete and explanatory first sentence. This article should have that too.
These are just a few of things I've noticed in the article's lede. I'd be happy to write my own version for you and others to look at. Or I can just, as you suggest, put up my words and wipe out the current content. Either way is fine with me, but I thought, perhaps, I wouldn't be a jerk. In all situations, we have the choice to go about something in a way that comes off like a jerk or not a jerk. I chose the latter.
Also, won't you sign in and make yourself known? I would be happy to have a productive discussion about this. Cheers, ask123 (talk) 18:56, 27 October 2008 (UTC)
Hello buddy. I was using another computer I couldn't sign in on. That is why I didn't sign in. Now you know who I am insofar as I care to reveal it. I'm glad you encourage me assume good faith. Otherwise you looked like a knowledgeable vandal to me, because that is mostly what you see here, intellectual wise guys (besides teenagers struggling with their potty training). Well, it looks to me as though we have a legitimate conflict of approach and views, something I seldom encounter. I'm not going to try and change what you are and I would not diminish your enthusiasm for the game. So the thing for me to do is bow out. I more or less answered you below. Many people do take a historical approach. Having been trained in history as well as science that is the approach I take. That is not your approach so you do not see the utility of it. In cases like this I cede the field. I usually offer some historical garnishment if it seem interesting or if the author(s) have tried to put some in. You don't see the point of all that, I know. The history of science is not irrelevant or off the mark and it does explain some scientific terms and concenpts. That is all I care to suggest at the moment; I know that it will take a major educational effort to get you to change your mind, which this article is not. Now, I would prefer you to use your enthusiasm to create something according to YOUR system of values and point of view. We don't want to waste legitimate enthusiasm, now do we? There are many way to approach the subject. I don't have to have it MY way! I don't want to see you just revert it. Then I would have to put tags of my own and also you wiould not have answered any of the questions in the discussion or done anything to raise the grade. So, by all means, take it in hand. I explained that below. I like working on articles, don't you? You entered the lists here. Now you have to tournay or look like a ... I am not going to say it. From what you just said I think you will love it. You won't be able to break away. There is plenty or room for articles written from a scientific viewpoint. Have at it. See below and best wishes. Take all the time you need. When you are done get those tags off of there. I will check in from time to time after I do the paragraph.Dave (talk) 23:31, 27 October 2008 (UTC)
On the contrary -- I think that a historical approach is extremely important one if one is to get a full grasp of the topic. I just don't see a need to jump into it before giving at least a contemporary definition of the solstice. This article wouldn't be complete without a describing the solstice from a historical perspective. I just don't see that as the main focus of the article (which should be the contemporary understanding of the solstice). I see it as an important component of it -- something to be touched upon in the intro and delved into in a section. ask123 (talk) 00:33, 28 October 2008 (UTC)

General Assessment[edit]

This article has a lot of good elements in it, the makings in fact of a good article. My bottom-line assessment is that it sprawls - it could be condensed and the English could be improved. It has an organization and I can't say really that it is not a good organization. It needs a hand to bring it all together and cut it down. Those tags at the top are representative of why it cannot be improved - no one can agree and the disagreers are intolerant and aggressive. The tags are all wrong and similar criticisms in the discussion are wrong-minded and intolerant. Unless you people can agree or show some open-mindedness this is going on as a class B or C article until someone higher-up takes a hand and gives the process some direction. I would like to say it will come down to a call for an expert. Let me say that this is a pre-expert call for cooperation. Without it things are going no further here. I would add to the call for references but I see that function is in large part taken care of by the links. You authors- go over your material, see if you can reduce the verbiage a bit. And, start weighing in on the intro - what kind of an intro is best? We may need to take a few votes. There is no "wrong" approach as long as it is accurate. (talk) 18:27, 27 October 2008 (UTC)

Comments on the right sort of intro[edit]

I invite you to comment in this section on the most appropriate intro as a prelude to taking a vote of some sort and getting this thing moving in the right direction. Whoever put the tags at the top gave no explanation at all. Let's discuss. (talk) 18:27, 27 October 2008 (UTC)

I gave a brief explanation in my edit summary, but apologies for not continuing on here on the talk page. I'm glad that a discussion is happnening. I made my last post before reading the last two comments. It seems that I may have been wrong about the other user. I'm glad that everyone, including him/her, is participating in a productive discussion.
I would agree with IP user above that English needs some improvement and the intro is sprawling. Also, the style of writing needs some shaping up to. It needs to be more concise, and the piece should read more like an informative, encyclopedia article. The first sentence, for example, should be plainly explainatory and the intro should follow that lead. Much of the information contained in the intro is good, but it needs to be re-ordered, re-worded and trimmed down. Thoughts? ask123 (talk) 19:05, 27 October 2008 (UTC)
I'd be happy to write up an alternative intro that still uses much of the information and wording of the current intro. Can't do it now, but I'll start on it this evening. ask123 (talk) 19:08, 27 October 2008 (UTC)
Well hello there. This is much more reasonable. If you would take this in hand I would appreciate it. I see you are not a history-type person. All right. Don't deprecate history though. The history of science is a legitimate adjunct to it. If you want to start by defining solstice from a scientific view that is fine by me. You will not really say much that is different from what the ancients said but you may not know that. Modern science explanations are fine. For the relativity - well, I think you are too quick there. The last two sections on solstice from the earth and sun are actually written from a relativistic point of view. It does not resort to true motion versus apparent motion but talks about the path of the sun from different points of view. So, what you want to do with the etymology - well, I leave it up to you. If you want to move it or put it in a note, fine, but the etymology is as the AHD states it, which I gave in a ref. I don't know if I would cut it out - people like their word origins. I'll leave it up to you. Maybe you want to reduce the history to a minimum. What I did not like about the first intro was that it did not define! It stated, the solstices are on such and such a day. Big deal. We knew that. Then it gave a lame etymological definition. But, if you want to take the field I cede it to you - I have other more historical irons in the fire I am eager to get back to. I want to finish that one section of ancient Greek terminology. I got one paragraph to go. But, as far as I am concerned you can do pretty much what you like. If you do get into history then I may have more to say. Remember, people may make fun of Wikipedia but millions read it and we owe the good folks some truth. Despite what some sentences in the handbook say, this is not an opinion poll except where absolutely necessary. An encyclopedia captures knowledge and most opinion is not that. So , have at it, but take it seriously. Don't concern yourself if you want to change anything I wrote or dump it. I want to see quality there. If you want to be the guiding hand, be it. I bow out. Best wishes.Dave (talk) 23:09, 27 October 2008 (UTC)
No worries...there are many mistaken impressions on the internet! As I wrote above: I think that a historical approach is extremely important one if one is to get a full grasp of the topic. I just don't see a need to jump into it before giving at least a contemporary definition of the solstice. This article wouldn't be complete without a describing the solstice from a historical perspective. I just don't see that as the main focus of the article (which should be the contemporary understanding of the solstice). I see it as an important component of it -- something to be touched upon in the intro and explored in great detail in a sub-section. ask123 (talk) 00:32, 28 October 2008 (UTC)
I'm starting from a standard definition of the solstice, as given in the Meriam Webster Dicitonary. I would like the lede to first explain exactly what the solstice is, which is an event in time that occurs twice a year. Once this precise definition has been given, we can touch upon the history and significance of the solstice -- both of which will be explored in greater detail in the sub-sections. Sound OK? ask123 (talk) 22:26, 28 October 2008 (UTC)
SOMETHING LIKE THIS (going to re-word it later): The solstice is either of the two points on the ecliptic at which its distance from the celestial equator is at its greatest. It is a temporal event that occurs twice a year, when the sun is directly over the Tropic of Cancer and over the Tropic of Capricorn respectively. ask123 (talk) 22:28, 28 October 2008 (UTC)
Or perhaps: A solstice is one of the two times of the year when the sun is furthest from the celestial equator. It is also one of two points on the ecliptic furthest away from the celestial equator, which is where the sun is at a solstice time.
The reader may be wondering what the signifance of this is and I regard it essential for the introduction the mention that the solstice gives rise to the longest and shortest daylight period of the year.
The history including etymology of solstice deserves its own section. Karl (talk) 10:48, 29 October 2008 (UTC)
The solstice is neither a time, nor a place, but an event that occurs at some place and time, defined by the Sun reaching its extreme position relative to locations on Earth. A good lead first has a simple definition, without using specialist terms like celestial equator, followed by a more precise technical one. −Woodstone (talk) 14:18, 29 October 2008 (UTC)
Karl: The intro will certainly address those points. I was just posting an idea for the first sentence or two. Certainly, the intro will mention that the solstices are the longest and shortest days of the year, as well as many other practical facts about the solstices, including their relationship to cultural and religious events. Also, I agree that there should be a section devoted to the solstices in history and section devoted to the etymology of the word.
Woodstone: If "celestial equator" and "ecliptic" are too complex, I will put it in more simple terms first. I was just posting an idea, not actual words to be used. If you go to the meriam webster definition of solstice, you will see that I simply lifted the dictionary definition. It needs to be re-worded.
Thanks, everyone, for your comments. I will have something churned out shortly. ask123 (talk) 15:37, 29 October 2008 (UTC)


Sorry for the delay! I've had so much (real world) work lately. Consequently, the revised intro is taking a bit longer than expected. But I will have something soon! ask123 (talk) 18:41, 3 November 2008 (UTC)


I've been reading through the talk page and I thought I'd throw something together. I'm in a bit of a hurry so I won't change the article but I will post my suggestions here and they can then be used, incorporated or discarded as you see fit. For clarify I will be indenting quotes from the article and double indenting my thoughts and suggested changes.

"Of the many ways in which solstice can be defined, one of the most common (and perhaps most easily understood) is by the astronomical phenomenon for which it is named, which is readily observable by anyone on Earth: a "sun-standing." This modern scientific word descends from a Latin scientific word in use in the late Roman republic of the 1st century BC: solstitium. Pliny uses it a number of times in his Natural History with the meaning it still has, but the word is in common use in other authors. It contains two Latin-language segments, sol, "sun", and -stitium, "stoppage.""
I don't mean to insult anyone but even the start, "of the many ways in which solstice can be defined" is unnecessarily complex. My suggested intro: "Solstice is usually defined as the moment, occuring twice a year, when the seasonal movement of the sun as seen from Earth halts. Solstice occurs on the shortest and longest days of the year. The word descends from the Latin term "solstitium" (roughly "sun stoppage") which was used in the 1st century BC in the Roman republic."
"By this "standing" the Romans meant a component of the relative velocity of the sun as it is observed in the sky. Relative velocity is the motion of an object from the point of view of an observer in a frame of reference"
I understand the intention here but this is a bit of an absurd juxtaposition. The Romans had no concept of special relativity, nor is an understanding of special relativity necessary to understand Solstice, since the concept predates relativity by a pretty massive amount of time. My suggestion is that ALL of the discussion of relative motion etc be shifted from the intro to a new section perhaps called "Astrophysical Explanation" or something along those lines. I also think it should be trimmed down; this isn't an article about special relativity.
"The term solstice can also be used in a wider sense, as the date (day) that such a passage happens."
I think the paragraph following this is fine. So ultimately I think the intro should consist of the first and last paragraphs, with the first paragraph simplified, and the discussion of relativity should be shifted to its own subheading within the article. (talk) 02:04, 11 November 2008 (UTC)
Yes, good plan. Intro is way too complex, and does not convey the information concisely. (Ethan Mitchell, forgetting to log in) —Preceding unsigned comment added by (talk) 04:13, 27 November 2008 (UTC)

Stuff I moved:

By this "standing" the Romans meant a component of the relative velocity of the sun as it is observed in the sky. Relative velocity is the motion of an object from the point of view of an observer in a frame of reference; for example, if it is true that seen from a space ship the Earth orbits the sun, it is also true that seen from the Earth the sun orbits the Earth. Relative velocity is quite real; that is, the perceived motions of objects are entirely relative to point of view; one and the same motion appears different from different frames of reference, and there is no absolute frame of reference from which all other motions are to be described.[1]

To an observer in inertial space, perhaps in a space craft, the Earth rotates about an axis and revolves around the sun in an elliptical path with the sun at one focus. This is the point of view of writers of astronomy textbooks. The Earth's axis is tilted rather than perpendicular to the plane of the Earth's orbit and this axis maintains a position that changes little (but does change) with respect to the background of stars. An observer on Earth therefore sees a solar path that is the result of both rotation and revolution.

The component of the sun's motion seen by an Earth-bound observer caused by the revolution of the tilted axis, which, keeping the same angle in space, is oriented toward or away from the sun, is an observed diurnal increment (and lateral offset) of the elevation of the sun at noon for roughly six months and observed daily decrement for the remaining six months. At maximum or minimum elevation the relative motion at 90° to the horizon stops and changes direction by 180°. The maximum is the summer solstice and the minimum is the winter solstice. The path of the sun, or ecliptic, sweeps north and south between the northern and southern hemispheres. Around the summer solstice the days are longest and the shortest around the winter solstice. When the path crosses the equator the days and nights are of equal length, a condition called an equinox. There are two solstices and two equinoxes.[2]

The term solstice can also be used in a wider sense, as the date (day) that such a passage happens.

Ethan Mitchell (talk) 04:27, 27 November 2008 (UTC)

The new lead by User:Elpincha is far from better than it was before. There is no relationship between the elliptic orbit of the earth around the sun and the occurrence of the solstice. The solstice only determined by the orientation of the earth's axis relative to the sun. Furthermore only in some cultures does the solstice mark the beginning of seasons. And even there, many other definitions of the seasons exist. So more work is needed. −woodstone (talk) 16:23, 8 December 2008 (UTC)

earth wobbles?[edit]

I am not too sure but this phenomenon always confused me say you have a rotating disc and you put an inclined stick / on one end of the disc when the disc rotates and the stick is on the other side, it becomes like \ however the same logic does not hold true for the earth. So does the axis actually tilt across when it goes from one side to the other? 12:29, 28 January 2009 (UTC)

The orientation in space of the Earth's axis stays the same all year round (except for a tiny amount of precession). The axis is not fixed in any way to the Sun or the orbit. The stick you have in mind is fixed to the rotating disk, and by this fixation, the disc's rotation exerts a torque on the stick and it rotates with it. −Woodstone (talk) 21:55, 28 January 2009 (UTC)

It is just observation. If the axis was like an unfixed thing on a disc too, it would still be bent in the same direction because, say it is heavier on one end and the centrifugal force causes it to bend, that bend would still have the same orientation. —Preceding unsigned comment added by Alokdube (talkcontribs) 08:23, 29 January 2009 (UTC)

I think the conservation of angular momentum would imply that the angular momentum has a magnitude and direction fixed w.r.t. a pivot, called the sun here. Assume there is no revolution, the angular momentum of the object is fixed at \ . now we take into account revolution causing another angular component around the pivot...sun going | . so | + \ has to be conserved in totality. —Preceding unsigned comment added by Alokdube (talkcontribs) 08:13, 11 February 2009 (UTC)

I'm not 100% clear on what your understanding of the situation is but perhaps you're considering the Sun's gravitational pull on the Earth to be like swinging a tennis ball on a string around yourself. It's not like that - the Sun's pull acts on the Earth's centre of gravity but it is not connected to it and has no effect on which way the Earth's axis of rotation points. This is why now (February) the north pole points away from the Sun while the south points towards it. This causes it to be winter in the northern hemisphere and summer in the south. Six months later the Earth's axis still points toward the same point in space (Polaris for north) but the Earth is on the other side of the Sun, so now the north pole points toward the Sun and experiences summer, and the south points away and has winter.

Even if one was to assume this is a case of rotation about a fixed axis, the earth would point in the same direction relative to the axis.i.e / becomes \ .. The angular momentum can either be defined about a point or an axis, and I conclude it is not the Sun in case of the earth, but rather the north star. 10:32, 7 April 2013 (UTC) — Preceding unsigned comment added by Alokdube (talkcontribs)

The revolution of the earth around the sun and the rotation of the earth on its axis are two separate motions, and thus have separate angular momentum vectors. The first points toward the ecliptic north pole in Draco, and the second currently points to the celestial north pole in Ursa Minor. The second wobbles around the first (see axial precession for more info.) --Lasunncty (talk) 03:47, 5 May 2016 (UTC)

Why different dates?[edit]

Hi. As far as I remember, within each and every one school book I've read, they've always written that summer solstice on northern hemisphere is june 22nd, not 20th or 21st. Same thing with winter solstice - 22nd in books. And equinoxes as well. Who's right and who's wrong? The proffessors who had written these textbooks or wiki editors? Thx in advance.-- (talk) 15:37, 29 March 2009 (UTC)

The trouble with schoolbooks is that they are often written simplisticly to more clearly explain new ideas to the student (ie they leave out certain details not essential to the central concept). The main reason for the variation in the date is that the time it takes the Earth to revolve around the Sun is not equal to a whole number of days (~365.25) - and so we have an extra day every 4 years. See the table in the top-right of the article for the exact dates (and times) of the solstices and equinoxes and you'll see the progression from year to year which then resets with each leap year. Secret Squïrrel, approx 17:10, 29 Markh 2009 (Earth Standard Time)

Most schools used to pivot on the Sun rather than the pole star. That itself starts the confusion. —Preceding unsigned comment added by Alokdube (talkcontribs) 08:48, 1 April 2009 (UTC)

Why does "summer solstice" redirect here[edit]

when Winter solstice gets its own article? Serendipodous 22:11, 10 April 2009 (UTC)

I am not entirely sure what happens with 'histories'
and redirects. I am not sure if a summer solstice
page existed prior to June, 2007, that was exactly
the same as the disambiguation page on the subject
that was renamed into the disambiguation page, or
whether the redirects somehow killed the history.
I have removed the redirect and copied this article
into the page for summer solstice, however it
definitely needs more editing to refer to the
summer one, much like the winter article refers to
the winter one.
I haven't bothered to look through the history of
the winter article. (talk) 21:49, 21 June 2009 (UTC)

What am I missing?[edit]

In the Geocentric view of the seasons section, there are two paragraphs which need explanation (or I am missing the obvious). One paragraph states "On the northern hemisphere the north is to the left, the Sun rises in the east...... and the next says "On the southern hemisphere the south is to the left, the Sun rises in the east ......". There is nothing to indicate that the observer on the island in the ocean was facing in opposing directions when the observations were made. Whenever anyone is facing east, north will always be to the left regardless of hemisphere (and vice versa if facing west). Anyone? Kaiwhakahaere (talk) 23:50, 7 September 2009 (UTC)

The statement relates to positions in the pictures. For observers on the northern hemisphere, the picture should be interpreted with the north situtated at the left side. For observers on the southern northern hemisphere, the pictures should be interpreted with the south situtated at the left side. −Woodstone (talk) 10:11, 8 September 2009 (UTC)
OK, but seems to me this article is presented for readers with foreknowledge of the subject, rather than readers trying to find out about the subject. Maybe it would be a good idea to add your explanation to the article? Kaiwhakahaere (talk) 21:52, 8 September 2009 (UTC)

elevation, yearly motion, perpendicular ... eh?[edit]

At maximum or minimum elevation, the relative yearly motion of the Sun perpendicular to the horizon stops and reverses direction.

What is this sentence trying to say? The yearly motion is not perpendicular to the horizon. Elevation (should be disambiguated to elevation (ballistics)?) is not otherwise explained, and that word usually means the distance of (something) from the horizon, which is relevant to daily motion not annual motion; but the minimum elevation of the visible sun is zero every day, so why "maximum or minimum"? —Tamfang (talk) 05:04, 29 July 2010 (UTC)

When I read that sentence yesterday, I was also a little perplexed. "When the angle of elevation of the sun at noon reaches maximum or minimum, the annual motion of the sun reverses direction" might be more suitable. Elevation is mentioned in the figure in celestial coordinate system but is not explained otherwise. However, the alternate term, altitude, is defined at celestial coordinate system#altitude. But for general readers, even it should be clarified as the "angle of altitude" (I prefer "angle of elevation"). — Joe Kress (talk) 05:47, 29 July 2010 (UTC)

The History Section is Incomplete.[edit]

The first people in recorded history to write down the standing sun with modern precision where the Kametians of Classical African Civilization, Kemet (Ancient Egypt).

The fact that Standing Sun as an astronomical, astrological, psychological and Holy Day comes into recorded history in Africa, thousands of years before the first Greeks wrote their first book should be added to the history section by someone knowledgeable on the subject if historicity is to be served. — Preceding unsigned comment added by Aunk (talkcontribs) 20:13, 22 December 2010 (UTC)

I see no "History" section, nor any statement that the Greeks (or anyone else) saw it first. —Tamfang (talk) 21:24, 22 December 2010 (UTC)

December and June[edit]

I recently became aware of the existence of December Solstice and June Solstice. I rewrote them (you'll see) and copied most of the categories from Solstice and Summer solstice and Winter solstice, without giving much thought to whether they're all appropriate. Go weed 'em if you like. —Tamfang (talk) 21:46, 13 May 2011 (UTC)


Unfortunately stitium is not in my dictionary; I can believe it's a reduced form of something like statium (compare artifact, artificial) but that's not there either. Also unfortunately, Bartleby (the cited reference) apparently no longer offers the American Heritage Dictionary. —Tamfang (talk) 03:12, 21 June 2011 (UTC)

I found the originally-cited definition here. As an interesting (to me, at least) side note, it looks like stitium is actually from sistere ("to stop") ([source]). Brian Geppert (talk) 22:07, 26 June 2011 (UTC)
In fact sistere comes from stāre by reduplication, so it's all one. —Tamfang (talk) 00:12, 29 June 2011 (UTC)

Civil twilight[edit]

The article states that (at midnight):

"Above 60° latitude the Sun would be even closer to the horizon, only 6.56° away from it. Then civil twilight continues the whole night."

Civil twilight ends when the Sun is 6° below the horizon, so if the Sun gets 6.56° away from the horizon, the civil twilight can't last the whole night. It nearly lasts the whole night, but saying it like the article does now, must be somewhat unprecise. Iceblock (talk) 15:40, 26 June 2011 (UTC)

Article should have image or diagram based on solargraphy[edit]

A pinhole photograph by Justin Quinnell is very helpful in understanding the concept of a solstice: [6]. I think that most readers of Wikipedia, especially those living in cities, are unaware of how the sun's observed path through the sky during a day relates to the previous day's path and the next day's path. These "solargraphy" images demonstrate the point nicely. Perhaps a diagram based on the idea would be better than photographs. Other links: [7][8][9][10]. —Mathew5000 (talk) 16:18, 21 December 2011 (UTC)

Done.[11] The image I added to the article is the only solargraph available on Commons and is sourced from this page of the European Southern Observatory. Mathew5000 (talk) 22:26, 25 December 2011 (UTC)

longest/shortest day on the equator[edit]

Rather than start an edit war, I would like to get other people's thoughts about this particular qualification: To the sentence "The day of the solstice is either the 'longest day of the year' or the 'shortest day of the year' for any place on Earth..." I added "(except the equator)" because every day is the same length on the equator. Mathew5000 feels that since the equator is of infinitesimal width, the qualification is unnecessary. Still, I think the qualification is important, because whether you are slightly north or slightly south of the equator determines if a given solstice is the longest or shortest day, and even if you are several miles away the difference may be so small that it is effectively nonexistent. --Lasunncty (talk) 11:11, 11 January 2012 (UTC)

In the theoretical case, if every day is the same length on the equator, than each day is both the shortest and the longest there. So the qualification is unnecessary. −Woodstone (talk) 13:51, 11 January 2012 (UTC)
Yes, I was thinking of it the same way as Woodstone, at a point on the Equator, every day is maximal (as well as minimal), including the solstices, so the statement is true without the parenthetical qualification. Or, another way of looking at it is that no place can be on the Equator since the Equator has zero width; everywhere is either north or south of the Equator. Basically, I want the lead paragraphs to be as simple as possible for ease of comprehension by everyone, particularly young people. And I just felt that talking there about the limiting case (the Equator) distracts from the main point. That said of course accuracy is more important than simplicity: if we need a parenthetical qualification or else it would be inaccurate then it should be there. But in this case I think we don't need it, at least not in the lead section. By the way thank you Lasunncty for starting this thread, I don't want to edit-war about it either! Also I'm surprised nobody commented on the other aspects of the edit I made re-working the lead, I replaced the old definition of solstice ("when the Sun's apparent position in the sky, as viewed from Earth, reaches its northernmost or southernmost extremes") because that definition seemed to rely on a particular definition of "northernmost" and "southernmost" that differs from the lay definition. I believe that the best initial definition of solstice, for purposes of a general encyclopedia, is in terms of how the Sun appears to an observer at the North and South Pole, since almost everyone knows what the Poles are and the term "highest in the sky" doesn't need to be defined further. Mathew5000 (talk) 07:04, 12 January 2012 (UTC)
If the atmospheric refraction at the horizon (34') and the semidiameter of the Sun (16') are considered, totalling 50', then at the equator the Sun must pass through this angle below the horizon at both sunrise and sunset throughout the year, causing the length of daylight to be longer than 12 hours throughout the year. However, at the equinoxes the Sun passes through this 50' vertically, passing through it rapidly, so a smaller amount is added to 12 hours. At the solstices the Sun passes through 50' at an angle, passing through it slowly, so a larger amount is added to 12 hours. This is comfirmed by using the Rising, Setting and Meridian Crossing of Solar System Bodies program provided by IMCCE at the Observatory of Paris, which shows that the length of daylight during 2012 is longer than 12 hours at the vernal equinox by 4.710 minutes and at the autumnal equinox by 4.680 minutes, whereas it is longer than 12 hours at the summer solstice by 5.412 minutes and at the winter solstice by 5.550 minutes.
Thus "except at the equator" is necessary, because at the equator the shortest day of the year occurs at the equinoxes while the longest day of the year occurs at the solstices. — Joe Kress (talk) 10:03, 12 January 2012 (UTC)
Yes, but then the same must be true close to the equator, and in a certain zone the original statement is invalid. −Woodstone (talk) 09:47, 13 January 2012 (UTC)
Equinoctial minimum daylight and solsticial maximum daylight generally occur on the equator at any arbitrary location (longitude) during that midnight-to-midnight day containing the equinox or solstice at that location. Absolute maximum/minimum daylight can occur only at that instant and longitude when the equinox or solstice occurs at local apparent solar noon, which depends on the Universal Time of the solstice or equinox as well as the equation of time. Even then, only a single equinox or solstice can occur at that location's noon. Moving a few arcminutes from the equator causes minimum daylight to move away from both equinoxes at the same time and toward the winter solstice, which is the December solstice north of the equator and the June solstice south of it. During this movement, maximum daylight continues to occur at the summer solstice. For example, at 15'N, minimum daylight has moved to 15 February and 26 October, or about one third of a season from the equinox on its way toward the northern winter solstice. The two minimum daylights merge at 30 arcminutes from the equator to form a broad low whose minimum occurs a few days away from the winter solstice. Minimum daylight reaches the winter solstice and becomes sharper at 40 arcminutes from the equator. The latter could be rounded to 1°. — Joe Kress (talk) 00:57, 20 January 2012 (UTC)

Capitalization[edit] HTML2011 (talk) 05:03, 10 April 2012 (UTC)

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Per the comment at WT:AST, it was suggested that the solstice articles be merged into one article. -- (talk) 00:49, 3 December 2012 (UTC)

non-Earthly solstices[edit]

This article needs coverage of solstices on other planets, such as found for equinox that covers other planets. -- (talk) 00:52, 3 December 2012 (UTC)

In the constellations section[edit]

I don't understand this section at all. How is a solstice "in a constellation"? Is this actually astrology rather than astronomy? If so, it has no place in this article. Btljs (talk) 09:09, 4 September 2015 (UTC)

Is it this: Constellation#IAU constellations? If so, a bit of explanation about what is actually pointing at this bit of sky would help non-astronomers like me. Btljs (talk) 09:15, 4 September 2015 (UTC)

On the celestial sphere, the ecliptic and equator are both great circles that intersect at the equinoxes. The solstices would be 90° away. --Lasunncty (talk) 09:42, 6 September 2015 (UTC)

Season Starts[edit]

I reverted a recent change, because it ignored the tradition in China of the equinoxes and solstices marking the middle of the seasons. The previous version mentioned both the marking of the start of season as in the West and the middle of the season, so is more NPOV. Karl (talk) 12:55, 3 November 2015 (UTC)

@Karl Palmen: The sentence "In many cultures the solstice marks either the beginning or the midpoint of winter or summer" is just too vague. I clarified it. Also, this is not an ussue of POV, it is an issue of relevance. For the english encyclopedia, our solstices are more relevant. But hey, I will try to fix that. Just give me a minute Outedexits (talk) 13:05, 3 November 2015 (UTC)
@Karl Palmen: I made a mention of other cultures now. By the way, do you have source for that claim that in the Chinese culture the solstices mark the midpoint of seasons? I'm willing to add it in the article for verification. Outedexits (talk) 13:12, 3 November 2015 (UTC)
@Outedexits: I'm satisfied with the your mention of other cultures. The Chinese practice shows up in the names they give to their solar terms. I'm also thankful for subsequent editors for making your changes more concise. Karl (talk) 12:55, 3 November 2015 (UTC)
@Karl Palmen: Thanks! Outedexits (talk) 14:27, 4 November 2015 (UTC)
This is a lot of nonsense:(maybe a tad harsh Btljs (talk) 15:37, 4 November 2015 (UTC)) if the summer solstice marked the beginning of summer then why do we refer to it as mid-summer's day? I think the first paragraph should establish the physical rather than the sociological definition. What is summer anyway? It only exists outside the tropics so to say that something global (or even semi-global) is happening is rather misleading. Can we work on a form of words here, which accurately describes the way solstices relate to temperate climate seasons and polar seasons? Btljs (talk) 14:53, 4 November 2015 (UTC)
@Btljs: Yes, perhaps it should be mentioned that the seasons are only outside the tropics. Well, go ahead and edit the article as you see fit. Then I will make some adjusts if necessary. Outedexits (talk) 16:15, 4 November 2015 (UTC)


  1. ^ The Principle of relativity was first applied to inertial frames of reference by Albert Einstein. Before then the concepts of absolute time and space applied by Isaac Newton prevailed. The motion of the sun across the sky is still called "apparent motion" in celestial navigation in deference the the Newtonian view, but the reality of the supposed "real motion" has no special laws to commend it, both are visually verifiable and both follow the same laws of physics.
  2. ^ For an introduction to these topics of astronomy refer to Bowditch, Nathaniel (1995 Edition). The American Practical Navigator: an Epitome of Navigation (pdf). Bethesda, Maryland: National Imagery and Mapping Agency. pp. Chapter 15 Navigational Astronomy. Retrieved 2008-10-19.  Check date values in: |date= (help)

2015 dec Solstice: 2015-Dec-22 04:47:57.771[edit]

It is very difficult to find the exact times of solstices and equinoxes, to better than a minute of resolution -- and therefore hard to resolve discrepancies in various sources. On the day of 2015 December Solstice, common media sources are stating 22dec15 at either 4:48 or 4:49 UTC/GMT. Which is more accurate?

This source has a handy any-year calculator that gives
Local = Mon Dec 21 2015 23:47:53 GMT-0500 (Eastern Standard Time)
UTC = Tue, 22 Dec 2015 04:47:53 GMT
TDT = Tue, 22 Dec 2015 04:49:20 GMT
but the footnotes explain that these times are only approximate, to about a minute of accuracy (and the following shows the UTC to be about 5 seconds off).
This source computes
NORTHERN  Year  Date  DoW    Time TDB  SOUTHERN    Delta T Est
Winter    2015 Dec 22 Tue at 04:49:04  Summer      +01m 09s
which yields 4:47:55 UTC
This is the best discussion of how hard it is to obtain exact times, and how to get them from an online NASA calculator:

Using that engine yields:

Ephemeris Type [change] :     OBSERVER
Target Body [change] :     Sun [Sol] [10]
Observer Location [change] :       Geocentric [500]
Time Span [change] :       Start=2015-12-22 4:47:55, Stop=2015-12-22 4:48:05, Intervals=20
Table Settings [change] :          QUANTITIES=1,9,20,23,24,30,31
Display/Output [change] :          default (formatted HTML)
2015-Dec-22 04:47:57.000     68.183653 269.9999909  -0.0001291
2015-Dec-22 04:47:57.500     68.183653 269.9999968  -0.0001291
2015-Dec-22 04:47:58.000     68.183653 270.0000027  -0.0001291
2015-Dec-22 04:47:58.500     68.183653 270.0000086  -0.0001291
Date__(UT)__HR:MN:SC.fff          CT-UT          ObsEcLon              ObsEcLat

Which leads to:

2015-Dec-22 04:47:57.271       68.183653 269.9999941  -0.0001291
2015-Dec-22 04:47:57.771       68.183653 270.0000000  -0.0001291
2015-Dec-22 04:47:58.271       68.183653 270.0000059  -0.0001291
Times are UTC (not UT1).
The dynamical Coordinate Time scale is used internally. It is equivalent to the current IAU definition of "TDB".

Giving a final result of:

2015-Dec-22 04:47:57.771 UTC (+68.183653 = CT/TDB)

In conclusion, 4:47:58 and 4:48 UTC is the proper rounded time; 4:49 seems somewhat wrong, for any general usage.- (talk) 17:32, 21 December 2015 (UTC)

more precise Solstice and Equinox times[edit]

The English speaking world seems to be limited to approximate Solstice and Equinox times, to about the nearest minute.
The French offer a more precise, to the second, master table:

2013       20      11:01:55        21      05:03:57        22      20:44:08        21      17:11:00
2014    20      16:57:05        21      10:51:14        23      02:29:05        21      23:03:01
2015    20      22:45:09        21      16:37:55        23      08:20:33        22      04:47:57
2016    20      04:30:11        20      22:34:11        22      14:21:07        21      10:44:10
2017    20      10:28:38        21      04:24:09        22      20:01:48        21      16:27:57
2018    20      16:15:27        21      10:07:18        23      01:54:05        21      22:22:44
Références :   mars • juin • sept. • déc.
Institut de mécanique céleste et de calcul des éphémérides

Most WP readers do not care about this -- but some might like access to the more accurate times. How can we provide such access in a good way? Would we ever want to replace our template master table with a more-precise master table of times? - (talk) 19:13, 22 December 2015 (UTC)

Just a link to the original source as cited in the French article will be fine. We don't need seconds in the actual text here. Btljs (talk) 19:37, 22 December 2015 (UTC)

Assessment comment[edit]

The comment(s) below were originally left at Talk:Solstice/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Everybody why don't you put definitions in laymans terms? maybe make it simpler? if you make it simpler more people recieve help and that's the point right to help people? Please take this into consideration Tzzzzz;0dfsfgsfgssddsssfgsdfgfdgsdffs02:57, 11 May 2007 (UTC) It would be helpful to say exactly where, as well as when, the solstices and equinoxes occur. That is, the sun is directly over only one particular point on the equator at an equinox. Also, does the plane of the ecliptic have anything to do with this subject?. —Preceding unsigned comment added by (talk) 23:50, 5 June 2009 (UTC)

Last edited at 06:27, 25 December 2011 (UTC). Substituted at 06:29, 30 April 2016 (UTC)