Talk:Summer solstice/Archive 1

Tweak table
Could who ever got the table information please: Thanks, LP-mn (talk) 17:33, 30 March 2011 (UTC)
 * extend it out a decade or two,
 * delete the oldest decade information and please
 * add the DAY of the week for these dates?

Closing bracket needed
✅

"the Tropic of Capricorn (23°26'S. The Sun reaches its highest position"

Topic is semi-locked, so I can't change it :-( — Preceding unsigned comment added by Mikeholden (talk • contribs) 10:46, 21 June 2011 (UTC)

The ancient times
The greeks and many other ancaint people considered this to be a very special day. I think we should have a section on that.


 * covered at Midsummer. TJRC (talk) 20:26, 21 June 2011 (UTC)

and the moon's axial tilt removed
i removed the "and the moon's" .. axial tilt from the intro. someone needs to cite a source to assert that the moon's axis of self rotation is perfectly parallel to that of the earth. would be an interesting fact if true, but in that case would be off topic in such an upfront position in the intro. please reintroduce this if a reliable source can be found but in a different more appropriate place CecilWard (talk) 19:18, 21 June 2011 (UTC)
 * It's not true. Nowhere close. Good catch removing it. --agr (talk) 02:34, 22 June 2011 (UTC)
 * Thanks. --SciCorrector (talk) 04:09, 22 June 2011 (UTC)


 * Indeed the Moon's tilt relative to the Ecliptic is very small, making a few polar crater floors permanently dark. —Tamfang (talk) 19:08, 22 June 2011 (UTC)

December and June
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)
 * Seeing as these are both covered in Solstice, is it really necessary for them to have their own pages? Makes more sense to have them redirect to the relevant part of Solstice. --Kftrendy (talk) 17:49, 24 June 2011 (UTC)

first day of summer?
Google has today's doodle named as "first day of summer". That would suggest wide usage, yet there is no mention in this page. The article First Day of Summer tells about an Icelandic holiday. 85.217.33.164 (talk) 20:56, 21 June 2013 (UTC)

Santa Barbara Celebration
I'm removing the following line from the article: "The largest summer solstice parade in North America took place in 1974, Santa Barbara, California." Although the sentence is footnoted [], the source in the foot note 1) is the website of the organizers of the event referenced - not an independent source, 2) makes clear that the event was first organized in 1974 but is now much bigger than it was 40 years ago, and 3) does not support the claim made in the sentence that it is North America's largest solstice parade, now or in the past. 79.76.121.211 (talk) 17:41, 7 May 2014 (UTC)

Wording of first line
"...when the Earth's axial tilt is closest to the sun at its maximum of 23° 26'..."

This leaves a couple of possible misinterpretations.

First, the Earth's axial tilt is constant. It doesn't have a maximum or minimum.

Second, the geometry is about the Sun's position in the sky. A summer solstice is when the Sun makes its closest approach to a pole. In the northern hemisphere, that's when the Sun has the highest positive declination. In the southern hemisphere it's the moment of the lowest (most negative) declination.

(Another geometric definition of a solstice would be the moment that the plane formed by the center of the Sun and the Earth's two poles is perpendicular to the plane of Earth's orbit.)

Joe

http://stars.astro.illinois.edu/celsph.html http://asa.usno.navy.mil/SecM/Glossary.html (see "solstice") —Preceding unsigned comment added by Iamhondo (talk • contribs) 20:17, 19 June 2010 (UTC)

The Earth's axial tilt is constant. It doesn't have a maximum or minimum.


 * This isn't quite true. However, changes in axial tilt are neglegible in the time span of a few years, so it can be assumed constant in this context.

A summer solstice is when the Sun makes its closest approach to a pole. In the northern hemisphere, that's when the Sun has the highest positive declination. In the southern hemisphere it's the moment of the lowest (most negative) declination.


 * The northern hemisphere part is true but the southern hemisphere part is false. While this describes the summer solstice for the northern hemisphere, it does not describe the summer solstice for the southern hemisphere rather, the winter solstice.


 * I've rephrased the sentence to read

...when the Earth's axial tilt is most inclined towards the sun at its maximum of 23° 26'...


 * so that it refers to the inclination instead. Hope this helps.  Set Sail   For The   Seven Seas   334° 26' 45" NET   22:17, 19 June 2010 (UTC)

Fuzzy writing
I disagree with the definition in the first sentence, not only because of the reasons cited elsewhere in this talk page, but also for the following reasons.

The article currently recites: "The summer solstice occurs exactly when the Earth's and the moon's axial tilt is most inclined towards the sun, ..."

First, I find it bizarre to include The Moon in the definition. If such thing was true, then by force some reference should be included bearing proof that the two axis, the Moon's and Earth's, are exactly parallel at all times. The latter is utterly false: Earth's axial tilt with regard to the Ecliptic is 23.44°, while the Moon's measures 1.5424°. Moreover, as the Moon orbits around the Earth, the Moon's inclination of 5.14° and its axial tilt of 6.68° (with respect to its orbit around the Earth) actually make the angle between both axis to vary continuously (see Cassini's Laws and Lunar libration)

Second, it is not "the axial tilt" that happens to be "inclined", it's the axis per se. Such fuzzy or careless writing is typical of cheap newspapers, not of an Encyclopedia. --SciCorrector (talk) 18:55, 21 June 2011 (UTC)

This seems to imply that the date of the solstice is the same all over the world "in reference to UTC.[4]" This isn't true. The astronomical event occurs at the same instant all over the world and can be on different days depending on where you are. If the solstice event is before midnight in one time zone and after midnight in the UHC, it will be on different days. Also footnote 4 doesn't support the content referenced. (Shootingstar (talk) 16:43, 20 June 2013 (UTC))

yeah where is the definition? — Preceding unsigned comment added by 146.244.137.169 (talk) 22:17, 4 February 2015 (UTC)

Proposed merge with Xiazhi
same topic Shizhao (talk) 14:07, 19 May 2015 (UTC)


 * oppose see Talk:Winter_solstice. Jimp 17:50, 19 May 2015 (UTC)

Semi-axis
This seems to me a rather obscure term to use here no? It seems confusing to me. Just about everyone understands what the rotational axis of the Earth is. — Preceding unsigned comment added by 69.121.188.60 (talk) 03:26, 13 June 2016 (UTC)

Add “Length of the day on the summer/winter solstice of the south”
Could we have something titled like “Length of the day on the summer solstice of the south” and “Length of the day on the winter solstice of the south”? 46.130.153.71 (talk) 19:09, 16 October 2016 (UTC)


 * What addition had you in mind? The length of day varies with latitude and local geography, of course.    D b f i r s   19:16, 16 October 2016 (UTC)

Figure refers to summer solstice instead of northern solstice
The figure titled "Leap shifting of the Gregorian Calendar" is subtitled "Date of Summer Solstice over 400 years", with the y-axis indicating June. In the southern hemisphere, the summer solstice is in December. Either the subtitle should be changed to northern solstice, or a note should be added to the page at the diagram. 196.215.28.28 (talk) 00:54, 29 January 2017 (UTC)


 * Good point. The file description is accurate, and I've changed the alt text, but ideally the caption on the diagram needs changing.  Can anyone do this?    D b f i r s   07:35, 29 January 2017 (UTC)

NPOV: Geocentric article
Articles about other planets refer here, including Swiss cheese features (Mars). This article is geocentric (okay, the other definition of geocentric), only discussing the summer solstice on Earth. Can we maybe have more of a general definition in the opener? Does it make sense to include information on summer solstices for other planets here? samwaltz (talk) 20:43, 14 November 2010 (UTC)


 * Disagree. This encyclopedia is intended for terrestrials only, until further notice. --SciCorrector (talk) 18:55, 21 June 2011 (UTC)


 * Not really. The lede refers to a "planet" in general terms. This article is more clearly focused on Astronomy (with a brief nod to festivals) than the longer and more clearly explained solstice article which focuses on what an observer on the surface of the earth sees, including the viewpoint of people in the tropics.

I think it would help to have (astronomy) inserted after this article's title.Martindo (talk) 00:03, 21 June 2017 (UTC)

Merger with Midsummer
I suggest that Midsummer should be merged with this article so that it can related to the festivites of the summer solstice as has been done with winter solstice. What does the community think? Thanks.  Set Sail   For The   Seven Seas   329° 6' 0" NET   21:56, 17 June 2010 (UTC)

I think there is some value in making a distinction between the astronomical and cultural impact of these dates. I would prefer not to merge if possible. Raises the question - should the Winter Solstice entry be split up? —Preceding unsigned comment added by 74.125.57.36 (talk) 09:11, 21 June 2010 (UTC)


 * Already tried that here. Also, the point of the merger is to make this article represent that cultural impact, while solstice represents the astronomical impact as is the case with Winter Solstice. Hope this helps.  Set Sail   For The   Seven Seas   195° 1' 15" NET   13:00, 21 June 2010 (UTC)


 * Do not merge. One article is on an astronomic phenomenon, the other is on a cultural phenomenon.  They can cross-reference each other, but they serve different purposes and usually different audiences, and should not be combined. TJRC (talk) 16:33, 21 June 2010 (UTC)

DO NOT MERGE. The cultural significance of Midsummer in Northern Europe is of sufficient interest and requires such detail for thorough discussion that merging them would inevitably diminish the accessibility and richness of the Midsummer reference. They should be cross-referenced. I agree that they serve different purposes and usually different audiences. Jraimundo (talk) 05:52, 31 July 2010 (UTC)


 * Do not merge. Agreeing with the above, midsummer is a cultural practice, it's a bit like asking to merge the page on Yule with winter solstice. SirShill (talk) 21:56, 7 March 2011 (UTC)


 * Do not merge. While obviously related, they are separate things.  What about linking to the Midsummer page in the section of Summer solstice that mentions the midsummer festivals instead?  Susan118   talk  23:45, 7 June 2011 (UTC)


 * Do not merge. Agree with Susan and so I added a clear pointer to the Midsummer page, which is an important and related topic. However, I oppose expansion of the text on festivals here. BTW, the ancients could detect northerly progression of the sun and the subsolar point, but they could not measure time precisely enough to calculate longest day. See Eratosthenes for example. Martindo (talk) 00:50, 21 June 2017 (UTC)

Comma lacking in the first sentence?
"The summer solstice (or estival solstice), also known as midsummer, occurs when a planet's rotational axis, or geographical pole on either its Northern or its Southern Hemisphere is most greatly inclined toward the star that it orbits." It seems to me that there should be a comma after "Southern Hemisphere". 145.132.75.218 (talk) 10:00, 21 June 2018 (UTC)


 * I agree. I'll make the change. Jc3s5h (talk) 10:37, 21 June 2018 (UTC)

Midsummer Day and the Summer Solstice are different dates
This article is wrong when it says that the "Summer solstice" is also known as midsummer. Midsummer Day (also known as Saint John's Day  - it is the Feast Day of Saint John the Baptist is on June 24, the Summer Solstice is on June 21. Vorbee (talk) 10:47, 21 June 2018 (UTC)


 * It's not that simple. The Cambridge Dictionary says summer solstice is one of the meanings for "midsummer".


 * However, the paragraph has a flat statement that the summer solstice is also known as midsummer, even on other planets. That doesn't seem like a very appropriate statement to make about regions near Earth's equator, where other terms are used to describe seasons, such as "wet" and "dry". Nor does it seem appropriate for uninhabitable planets, where there are (probably) no organisms to experience summer or winter. Jc3s5h (talk) 11:34, 21 June 2018 (UTC)

Move discussion in progress
There is a move discussion in progress on Wikipedia talk:Disambiguation which affects this page. Please participate on that page and not in this talk page section. Thank you. —RMCD bot 20:01, 9 October 2019 (UTC)

What it is and what it's not: new section on Distinctions
The summer solstice is the longest day of the year, but it's NOT the day of earliest sunrise nor latest sunset. Also, this article should pay as careful attention to tropical latitudes as the solstice article, which clearly notes that the day of maximum altitude of the sun varies in the tropics, the subsolar point.Martindo (talk) 00:35, 21 June 2017 (UTC)

This is a scientific subject, and if you want to get really scientific, then the summer solstice is actually NOT the longest day of the year, it's simply the day with the most daylight hours. Strictly speaking, the length of day averages 24 hours, which is to say that some days are a little bit shorter, and some days are a bit longer. When speaking of the actual longest day, you must refer to the longest solar day (a solar day is the time that it takes for the sun to go from the same point in the sky from one day to the next). That day is December 21st, and it is for the entire planet, not just the southern hemisphere. Calling the summer solstice the "longest day of the year" is simply another way that the science-illiterate screw up anything scientific.

One thing that I've been wondering is whether locations between the Tropics get two days per year with most daylight hours, as the sun passes directly overhead twice per year. If that is the case, then the summer solstice is the day with the most daylight hours, but only in regions between each hemisphere's Tropic and pole (so not for the entire hemisphere). (184.68.50.142 (talk) 18:26, 14 September 2018 (UTC))


 * The lead is more precise in using "longest period of daylight". Common usage of "longest day" is understood to mean the same thing, but perhaps we should clarify when the term is used elsewhere?   Dbfirs  18:36, 14 September 2018 (UTC)

Digressing a little, maybe also add clarification to define and link to altitude angle of the horizontal coordinate system as celestial coordinate system, specifically, so as not to confuse any reader accidentally looking up the article for aviation/atmospheric altitude. Maybe we could also reference the relation of the respective tropic to the most northern/sourthern incidence of subsolar point in a given year, i.e. the time and occurrence of the summer solstices. DougEMandy (talk) 22:53, 20 June 2021 (UTC)

exact solstice times
The article includes a table of equinoxes and solstices for a ten-year period. All the times are rounded to the nearest minute. What are the exact times? How are these calculated? TypoBoy (talk) 03:24, 23 June 2017 (UTC)


 * The time of the June equinox is when the apparent geocentric celestial longitude of the Sun, using the true equator and equinox of date, passes through 90°. There are many software choices for computing this, including JPL Horizons On-Line Ephemeris System. Jc3s5h (talk) 11:41, 23 June 2017 (UTC)


 * You can find more exact times (to the nearest second) on the French WP (under Solstice). AstroLynx (talk) 11:52, 23 June 2017 (UTC)

Might we also find references to include or describe generally locations where the zenith crosses each tropic at the given time of any given year? DougEMandy (talk) 22:53, 20 June 2021 (UTC)

Clarification
Ok, so it says on March 20, 2020, it says the spring equinox was at 03:50 UTC. I am in New York where at the time it was UTC-4. Is it 3:50 AM in each specific time zone, or 03:50 UTC(which is 11:50 PM March 19 the day before). --HurricaneTracker495 (talk) 23:15, 6 December 2020 (UTC)
 * The answer is in the heading of the table, which reads "UT date and time of equinoxes and solstices on Earth. "UT" stands for Universal Time, which is an umbrella term for various specific forms of universal time such as UT0, UT1, UT2, or UTC. Since the times are only given to the nearest minute, it isn't necessary to specify which form of UT applies.
 * Also, the table extends 5 years into the future. The calculations are done based on a form of time that flows uniformly, Terrestrial Time (TT). TT is usually realized with atomic clocks. The various forms of UT follow the rotation of the Earth, which is somewhat irregular. The time at which astronomical events will occur 5 years from now, stated in UT, cannot be calculated to the nearest second due to this irregularity.

I think it might be helpful if we find references for where the location of the summer solstice's zenith on the corresponding tropic occurs in any given year. Perhaps not necessarily a precise calculation table, but at least a general description of how the solstice's zenith lands on a certain celestial coordinate in any given year. DougEMandy (talk) 22:53, 20 June 2021 (UTC)

Merger proposal
I propose merging Xiazhi into Summer solstice. This is basically the same thing and is written in the same article in Chinese Wikipedia. -Miklcct (talk) 11:14, 5 January 2022 (UTC)


 * See Talk:Winter solstice for detailed discussion. — Preceding unsigned comment added by Miklcct (talk • contribs) 11:24, 5 January 2022 (UTC)
 * In Chinese, the word "xiazhi" literally means "summer solstice", which is why the two articles are put into one. However, the Xiazhi article on the English Wikipedia describes the Chinese solar term beginning at the summer solstice, and specifically the solar term.
 * In other words, xiazhi and the summer solstice are similar, but not quite the same. Merging the two articles would be like merging the article for the geography of the USA with the one for the geography of North America.
 * The same applies for the Winter Solstice and Dongzhi Festival by the way.
 * TheOneTEM (definitely a human) (talk) 11:13, 9 July 2022 (UTC)

Oppose merge. I think the topics are different enough that they should remain separate. The entire focus of Xiazhi involves the Chinese observance. Joyous! | Talk 03:45, 15 December 2022 (UTC)


 * Oppose merge. Xiazhi concentrates on the Chinese calendaring of the solstice; this article is on the event/phenomenon itself. TJRC (talk) 04:24, 15 December 2022 (UTC)