news sciences: Dates of sun’s entry into each constellation of the Zodiac

Sun’s path through the zodiac.

The sun resides at a longitude of 0^o on the ecliptic at the March equinox. The sun is at 90^o ecliptic longitude at the June solstice, 180 ^o ecliptic longitude at the September equinox and 270^o ecliptic longitude on the December solstice. Image via Wikipedia

You may know that the real sun in the real sky does not appear in front of a constellation of the Zodiac within the same range of dates you’ll see listed in astrological horoscopes. That’s because astrology and astronomy use different systems. Astrologers typically indicate the sun’s position with signs whereas astronomers use constellations. We were asked for:

… a list of the constellations that fall on the ecliptic with the exact degrees.

And we’ve located this information in Guy Ottewell’s Astronomical Calendar. Below, you’ll find the dates for the sun’s entry into each zodiacal constellation, plus the sun’s ecliptic longitude – its position east of the March equinox point on the ecliptic – for each given date.

We are using the boundaries for the zodiacal constellations established by the International Astronomical Union in the 1930s.

Date of sun’s entry into each zodiacal constellation (and corresponding ecliptic longitude):

Dec 18, 2015: Sun enters constellation Sagittarius (266.55^o)

Jan 20, 2016: Sun enters constellation Capricornus (299.68^o)

Feb 17, 2016: Sun enters constellation Aquarius (327.85^o)

Mar 11, 2016: Sun enters constellation Pisces (351.54^o)

Apr 18, 2016: Sun enters constellation Aries (29.05^o)

May 13, 2016: Sun enters constellation Taurus (53.43^o)

Jun 21, 2016: Sun enters constellation Gemini (90.40^o)

Jul 20, 2016: Sun enters constellation Cancer (118.22^o)

Aug 10, 2015: Sun enters constellation Leo (138.15^o)

Sep 16, 2016: Sun enters constellation Virgo (174.12^o)

Oct 30, 2016: Sun enters constellation Libra (217.77^o)

Nov 22, 2016: Sun enters constellation Scorpius (241.11^o)

Nov 29, 2016: Sun enters constellation Ophiuchus (248.00^o)

Dec 18, 2016: Sun enters constellation Sagittarius (266.57^o)

Source: Astronomical Calendar 2015 and 2016

Earth-centered ecliptic coordinates as seen from outside the celestial sphere. Ecliptic longitude (red) is measured along the ecliptic from the vernal equinox at 0^o longitude. Ecliptic latitude (yellow) is measured perpendicular to the ecliptic. Image via Wikimedia Commons

Constellations of the Zodiac:

Click here to learn dates the sun enters each sign of the Zodiac.

from EarthSky http://ift.tt/1Peodxr