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Moon and Regulus on January 14

Tonight – January 14, 2017 – look late at night, toward the east, for the bright waning gibbous moon. Although the star Regulus shines close to the January 14 moon, it might be hard to see this star in the moonlit glare.

What if you look and don’t see the moon? That’ll be because the moon has risen yet. The exact rising times for the moon and Regulus depend on where you live worldwide. Click here for some recommended sky almanacs that’ll provide this information for your part of the world. Or use this custom sunrise-sunset calendar, and be sure to click the box for moonrise times.

Regulus is the brightest star in the constellation Leo the Lion. In skylore, it’s considered the Lion’s Heart.

The moon and Regulus will shine especially close together on the sky’s dome tonight as viewed in the Americas. In fact, the moon will actually occult (pass in front of) Regulus, as viewed from southern South America. Click here for more information on this occultation.

In Cenral America and South America, the moon actually occults Regulus. Here, in North America, it's a very close pairing of the moon and Regulus.

In North America on January 14, we won’t see an occultation of Regulus by the moon, but we will see a very close pairing of the moon and this star. Miss ’em on the 14th? Regulus will still be somewhat near the moon on January 15.

Regulus is located along the ecliptic, or path of the sun, moon and planets in our sky. The moon shifts from year to year with respect to this path, but currently it’s situated such that it’ll occult Regulus every month for some months to come. The first of the series of monthly lunar occultations of Regulus started on December 18, 2016. The series will conclude on April 24, 2018. Of course, you have to be on the right spot on Earth to witness any one of these lunar occultations of Regulus.

The moon travels eastward in front of the constellations of the zodiac in a period of about 27 and one-third days. So that’s why the moon will next occult Regulus on February 11, 2017.

Whether or not you can see the occultation, we can all see Regulus near the moon. After rising, the moon and Regulus will climb upward and western throughout the night, until reaching their high point in the sky around 2 to 3 a.m. local time (on January 15). Afterwards, the moon and Regulus will start their descent westward, to lord over the western sky at dawn.

The moon and Regulus, just like the sun, cross the sky each day from east to west. That’s because the Earth rotates on its axis from west to east each day. Although the moon goes westward relative to our earthly terrain, it actually moves eastward relative to the stars. Therefore, you’ll see the moon farther east relative to Regulus tomorrow evening, on January 15.

Bottom line: Look for the twosome – the moon and Regulus – to climb above the eastern horizon around mid-evening on January 14, 2017.

Bruce McClure