Limerick Astronomy Club: Sky at night in March

The moon is a very useful object for helping to locate and identify different stars.

On March 5 the growing moon (gibbous moon) will be located close to the twin stars in the constellation Gemini. If you look to the north of the moon you will be able to identify them as Castor and Pollux. Looking to the south of the moon you will see another prominent star, Procyon which is located in the constellation Canis Minor. In fact these three stars form part of an asterism (a noticeable pattern of stars) that is visible in the winter months – the winter hexagon. Moving clockwise from Pollux, to the golden star Capella, down towards Aldebaran and onto Rigel (the star that forms the right foot of Orion) and finally around to Sirius (the brightest star in the night sky) completes the winter hexagon.

The full moon in March, falls on the 9th and is often referred to as the Worm Moon. The naming of this full moon relates to the softening of the ground and the reappearance of earthworms indicating that spring is on its way. This full moon is also the first of three supermoons this year, a time when the full moon coincides with perigee (when the moon is closest to the Earth in its orbit).

If you are an early riser, the dark mornings will provide an opportunity to view three planets later in March. An hour before sunrise on March 19, you will be able to see Saturn, Jupiter and Mars rising above the south east horizon. Use the waxing crescent moon to help you locate these planets. As the fourth brightest object in the night sky, Jupiter will be easily spotted as the brightest of the three planets. In contrast, Mars is the faintest morning planet but shining as brilliantly as a 1st magnitude star will make it clearly visible.

As the New Moon falls on March 24th, close to the spring equinox, it is the best time for viewing the zodiacal light. A hazy pyramid or wedge of light extending up from the western horizon is best seen approximately 90 minutes after sunset and under dark skies away from the light pollution of towns and cities. This mysterious light is caused by the sun reflecting off interplanetary dust particles concentrated in the plane of the solar system (the eliptic). At this time of the year the eliptic is nearly perpendicular to the horizon creating this eerie phenomenon.

Limerick Astronomy Club email limerickastronomyclub @gmail.com