On September 16, 2016, the sun exits the constellation Leo and enters the constellation Virgo. The sun will remain in front of the constellation Virgo the Maiden until it enters the constellation Libra the Scales on October 30. Please notice that we’re talking about astronomical constellations here, not astrological signs. You’ll find dates of sun’s entry into each constellation of the zodiac, here.
When the equinox arrives on September 22, 2016 – bringing autumn to the Northern Hemisphere and spring to the Southern Hemisphere – the sun will be in front of the constellation Virgo. And so it has been for thousands of years.
However, over the long course of time, the sun hasn’t always been in front of Virgo at the Northern Hemisphere’s autumnal equinox (Southern hemisphere’s spring equinox).
And, what’s more, the sun won’t remain in front of this constellation at the September equinox, indefinitely.
It was in the year 730 B.C. that the Northern Hemisphere’s autumnal equinox sun passed out of the constellation Libra and into the constellation Virgo. Looking into the future, the September equinox sun will cross over into the constellation Leo in the year 2439. These dates are based upon the constellation boundaries as defined by the Astronomical Astronomical Union in the 1930s.
Relative to the backdrop stars, the March and September equinox points shift about one degree westward along the ecliptic in 72 years, or 30o westward through the constellations of the zodiac in about 2,160 years.
In our day and age, the sun annually passes in front of the constellation Virgo from about September 16 until October 30.
Bottom line: On September 16, 2016, the sun exits the constellation Leo and enters the constellation Virgo. The sun will stay in Virgo until it enters Libra on October 30.
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.