Moon at Ascending Node

   Thursday the 25^th of September at 17:40 UT (12:40 pm CDT) our Moon will be crossing the plane of the ecliptic moving north. This is known as the ascending node, one of two intersections the Moon’s orbital path (dark green line) has with the ecliptic. Note the ecliptic is the line with ‘Oct’ however that is a reference to when the Sun will be at that point along the ecliptic and not the date for this node crossing.

   That evening look for the very thin waxing crescent Moon to be close to the bluish-white star Spica in Virgo. This may be an opportunity to see an extremely young Moon, not the record however. The Moon and Spica will be less than 20^o from the Sun making this even more of a challenge. If I am able to see the Moon, for example, my best time would be a few minutes before Moonset at 7:55 pm CDT (my local time). At that time the Moon will be approximately 2.5% to 3.0% illuminated, and will be approximately 1.76 days old.
   Here is a graphic showing the Moon and Spica as viewed through 7×50 binoculars. In the graphic I have removed the horizon to show more clearly the separation between the Sun and the Moon/Spica pair.
   
   
   


   Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.
Filed under: Astronomy, Astrophotography, Classroom, Earth and Space, Moon, Observing, Solar System Exploration Tagged: 7x50 binoculars, ascending node, astronomy, astrophotography, crescent Moon, ecliptic, moon, node crossing, observing, orbit around the sun, the Moon