The moon is some days past full, so it’s rising late at night. These next several nights – December 5, 6 and 7, 2020 – you might catch the moon and star Regulus – brightest star in the constellation Leo the Lion – rising in the east from mid-to-late evening. If you’re not a night owl, you can always get up before daybreak to view this waning gibbous moon and star Regulus in the morning sky. You’ll recognize them easily. Look first for the moon. That nearby bright star will be Regulus.
Want to know when the moon and Regulus rise into your sky? Then go to Sunrise Sunset Calendars for the moon’s rising time (remember to check the moonrise and moonset box). Or try Stellarium online. It can help you find the rising time for Regulus for your specific location on the globe.
Regulus represents the Heart of Leo the Lion. It’s the only 1st-magnitude star to sit almost squarely on the ecliptic, the sun’s apparent annual path in front of the constellations of the zodiac. Of course, the sun’s apparent motion in front of the background stars is really a reflection of Earth’s revolution around the sun.
Regulus is regarded as the most important of the four Royal Stars of ancient Persia. Possibly, Regulus’ proximity with the ecliptic elevated this star’s status. These Royal Stars mark the four quadrants of the heavens. They are Regulus, Antares, Fomalhaut, and Aldebaran.
Four to five thousand years ago, the Royal Stars defined the approximate positions of equinoxes and solstices in the sky. Regulus reigned as the summer solstice star, Antares as the autumn equinox star, Fomalhaut as the winter solstice star, and Aldebaran as the spring equinox star. Regulus is often portrayed as the most significant Royal Star, possibly because it symbolized the height and glory of the summer solstice sun. Although the Royal Stars as seasonal signposts have changed over the long course of time, they still mark four quadrants of the heavens.
The star Regulus coincided with the summer solstice point some 4,300 years ago. In our time, the sun has its annual conjunction with Regulus on or near August 23, or about two months after the summer solstice, that is, one month before the autumn equinox.
Regulus will mark the autumn equinox point some 2,100 years in the future.
Bottom line: Let the waning gibbous moon show you Regulus, Leo’s brightest star, as the moon parades through the constellation Leo the Lion these next several nights!