Editing Zodiac (section)

== Constellations ==
{{multiple image
|image1=Constellations ecliptic equirectangular plot.svg
|image2=A Mercator map of the starry heavens (William Croswell, 1810).jpg
|direction=vertical
|width=420
|footer=These two maps of the constellations, made two centuries apart, both show the zodiac constellations along a curved line representing the [[ecliptic]].
}}
[[File:Ophiuchus.jpg|thumb|upright=1.1|18th-century [[star chart]] illustrating the feet of [[Ophiuchus]] crossing the ecliptic]]

In [[Sidereal and tropical astrology|tropical astrology]], the [[astrological sign|zodiacal signs]] are distinct from the [[constellation]]s associated with them, not only because of their drifting apart due to the precession of equinoxes but because the physical constellations take up varying widths of the ecliptic, so the Sun is not in each constellation for the same amount of time.<ref name=EdwardJ>{{cite book|last=James|first=Edward W.|title=Philosophy of science and the occult|date=1982|publisher=State University of New York Press|location=Albany|isbn=0873955722|editor=Patrick Grim}}</ref>{{rp|25}} Thus, [[Virgo (constellation)|Virgo]] takes up 5 times as much [[ecliptic longitude]] as [[Scorpius (constellation)|Scorpius]]. The zodiacal signs are an abstraction from the physical constellations, and each represent exactly {{frac|1|12}}th of the full circle, but the time spent by the Sun in each sign varies slightly due to the eccentricity of the [[Earth's orbit]].

[[Sidereal and tropical astrology|Sidereal astrology]] assigns the zodiac sign approximately to the corresponding constellation. This alignment needs recalibrating every so often to keep the alignment in place.

The ecliptic intersects with 13 constellations of [[Ptolemy]]'s ''[[Almagest]]'',<ref>{{cite book | last1=Peters | first1=Christian Heinrich Friedrich | author1-link=Christian Heinrich Friedrich Peters | first2=Edward Ball | last2=Knobel | author2-link=Edward Knobel | url=http://hbar.phys.msu.ru/gorm/almagest/Peters.htm | title=Ptolemy's Catalogue of Stars: a revision of the Almagest] | publisher=Carnegie Institution of Washington | year=1915 | access-date=19 June 2006 | archive-date=29 August 2013 | archive-url=https://web.archive.org/web/20130829023007/http://hbar.phys.msu.ru/gorm/almagest/Peters.htm | url-status=dead }}
{{cite book |last=Ptolemy |title=Almagest |orig-year=2nd cent. |date=1982 |editor=R. Catesby Taliaferro |page=239 |chapter=VII.5}} Ptolemy refers to the constellation as ''Septentarius'' "the serpent holder".</ref> as well as of the more precisely delineated [[IAU designated constellations]]. In addition to the twelve constellations after which the twelve zodiac signs are named, the ecliptic intersects [[Ophiuchus]],<ref name=Tatum2010>{{cite journal | title=The Signs and Constellations of the Zodiac | last=Tatum | first=Jeremy B. | journal=Journal of the Royal Society of Canada | volume=104 | issue=3 | page=103 | date=June 2010 | bibcode=2010JRASC.104..103T }}</ref> the bottom part of which interjects between Scorpius and Sagittarius. Occasionally this difference between the astronomical constellations and the [[astrological sign]]s is mistakenly reported in the popular press as a "change" to the list of traditional signs by some astronomical body like the IAU, [[NASA]], or the [[Royal Astronomical Society]]. This happened in a 1995 report of the ''[[BBC Nine O'Clock News]]'' and various reports in 2011 and 2016.<ref>{{cite journal |author=Kollerstrom, N. |title=Ophiuchus and the media |journal=The Observatory |date=October 1995 |volume=115 |pages=261–262 |publisher=KNUDSEN; OBS |bibcode=1995Obs...115..261K}}</ref><ref>The notion received further international media attention in January 2011, when it was reported that astronomer Parke Kunkle, a board-member of the Minnesota Planetarium Society, had suggested that Ophiuchus was the zodiac's "13th sign". He later issued a statement to say he had not reported that the zodiac ought to include 13 signs instead of 12, but was only mentioning that there were 13 constellations; reported in ''Mad Astronomy'': [http://io9.com/5733004/your-zodiac-sign-may-have-changed-this-week "Why did your zodiac sign change?"] {{Webarchive|url=https://web.archive.org/web/20110625093016/http://io9.com/5733004/your-zodiac-sign-may-have-changed-this-week |date=25 June 2011 }} 13 January 2011.</ref><ref>{{Cite news |url=http://www.slate.com/blogs/bad_astronomy/2016/09/26/no_nasa_didn_t_change_your_astrological_sign.html |title=No, NASA Didn't Change Your Astrological Sign |first=Phil |last=Plait |newspaper=Slate Magazine |date=26 September 2016 |author-link=Phil Plait |access-date=2 October 2016 |archive-date=2 October 2016 |archive-url=https://web.archive.org/web/20161002070120/http://www.slate.com/blogs/bad_astronomy/2016/09/26/no_nasa_didn_t_change_your_astrological_sign.html |url-status=live }}</ref>

Some "parazodiacal" constellations are touched by the paths of the planets, leading to counts of up to 25 "constellations of the zodiac".<ref name=mosley>{{cite web |url=http://www.ips-planetarium.org/?page=a_mosley1999b |publisher=International Planetarium Society |date=2011 |first=John |last=Mosley |title=The Real, Real Constellations of the Zodiac |access-date=21 March 2017 |archive-date=1 July 2017 |archive-url=https://web.archive.org/web/20170701021831/http://www.ips-planetarium.org/?page=a_mosley1999b |url-status=live }}</ref> The ancient Babylonian [[MUL.APIN]] catalog lists [[Orion (constellation)|Orion]], [[Perseus (constellation)|Perseus]], [[Auriga (constellation)|Auriga]], and [[Andromeda (constellation)|Andromeda]]. Modern astronomers have noted that planets pass through [[Crater (constellation)|Crater]], [[Sextans]], [[Cetus]], [[Pegasus (constellation)|Pegasus]], [[Corvus (constellation)|Corvus]], [[Hydra (constellation)|Hydra]], [[Orion (constellation)|Orion]], and [[Scutum (constellation)|Scutum]], with [[Venus]] very rarely passing through [[Aquila (constellation)|Aquila]], [[Canis Minor]], [[Auriga (constellation)|Auriga]], and [[Serpens]].<ref name=mosley />

Some other constellations are mythologically associated with the zodiacal ones: [[Piscis Austrinus]], The Southern Fish, is attached to Aquarius. In classical maps, it swallows the stream poured out of Aquarius' pitcher, but perhaps it formerly just swam in it. [[Aquila (constellation)|Aquila]], The Eagle, was possibly associated with the zodiac by virtue of its main star, [[Altair]]. [[Hydra (constellation)|Hydra]] in the Early Bronze Age marked the [[celestial equator]] and was associated with Leo, which is shown standing on the serpent on the [[Dendera zodiac]].<ref name=Rogers_1998>{{cite journal
 | title=Origins of the ancient constellations: I. The Mesopotamian traditions
 | last=Rogers | first=J. H.
 | journal=Journal of the British Astronomical Association
 | volume=108 | issue=1 | pages=9–28
 | date=February 1998 | bibcode=1998JBAA..108....9R
}}<br>{{cite journal
 | title=Origins of the ancient constellations: II. The Mediterranean traditions
 | last=Rogers | first=J. H.
 | journal=Journal of the British Astronomical Association
 | volume=108 | issue=2 | pages=79–89
 | date=April 1998 | bibcode=1998JBAA..108...79R
}}</ref>

{| class="wikitable" style="text-align:left"
|-
! Name
! 1977 [[International Astronomical Union|IAU]] boundaries<ref name=Shapiro>[http://www.ips-planetarium.org/?page=a_shapiro1977 The Real Constellations of the Zodiac.] {{Webarchive|url=https://web.archive.org/web/20160328090559/http://www.ips-planetarium.org/?page=a_shapiro1977 |date=28 March 2016 }} Lee T. Shapiro, director of Morehead Planetarium University of North Carolina (Spring 1977)</ref> (approximate)
! Solar stay<ref name=Shapiro/>
! Brightest star
|-
| [[Aries (constellation)|Aries]]
| {{Zodiac date IAU|0}}
| 25 days
| [[Alpha Arietis|Hamal]]
|-
| [[Taurus (constellation)|Taurus]]
| {{Zodiac date IAU|1}}
| 37 days
| [[Aldebaran]]
|-
| [[Gemini (constellation)|Gemini]]
| {{Zodiac date IAU|2}}
| 31 days
| [[Pollux (star)|Pollux]]
|-
| [[Cancer (constellation)|Cancer]]
| {{Zodiac date IAU|3}}
| 20 days
| [[Beta Cancri|Al Tarf]]
|-
| [[Leo (constellation)|Leo]]
| {{Zodiac date IAU|4}}
| 37 days
| [[Regulus]]
|-
| [[Virgo (constellation)|Virgo]]
| {{Zodiac date IAU|5}}
| 45 days
| [[Spica]]
|-
| [[Libra (constellation)|Libra]]
| {{Zodiac date IAU|6}}
| 23 days
| [[Beta Librae|Zubeneschamali]]
|-
| [[Scorpius (constellation)|Scorpius]]
| {{Zodiac date IAU|7}}
| 7 days
| [[Antares]]
|-
| [[Ophiuchus (constellation)|Ophiuchus]]
| {{Zodiac date IAU|8}}
| 18 days
| [[Alpha Ophiuchi|Rasalhague]]
|-
| [[Sagittarius (constellation)|Sagittarius]]
| {{Zodiac date IAU|9}}
| 32 days
| [[Epsilon Sagittarii|Kaus Australis]]
|-
| [[Capricornus (constellation)|Capricornus]]
| {{Zodiac date IAU|10}}
| 28 days
| [[Delta Capricorni|Deneb Algedi]]
|-
| [[Aquarius (constellation)|Aquarius]]
| {{Zodiac date IAU|11}}
| 24 days
| [[Beta Aquarii|Sadalsuud]]
|-
| [[Pisces (constellation)|Pisces]]
| {{Zodiac date IAU|12}}
| 38 days
| [[Eta Piscium|Alpherg]]
|}