By Ron Sutcliffe
The majestic natural stone pillars of the Chimney Rock formation have a unique connection to the major standstill of the moon. Seen from the Great House Pueblo, the stone towers are slightly out of line with each other, framing a narrow window of sky between them. At sunset near the day of the Winter Solstice during the MLS, the full moon rises between the stone pillars, caught in this thin window of sky. The phenomenon is only visible at limited locations on the mesa top (from the center of the eastern kiva to the north).
In preparation for surveying exact dates and times for these unique viewing events, star gazing observations related to the Major Lunar Standstill have begun as the moon traverses across the sky in its 18.6 year cycle, and you may want to engage in some star gazing tonight and Wednesday night about 8:30 pm (depending on clouds). The moon will be next to Elnath, the second brightest star in constellation Taurus, which will be just north of the moon and about 4 or 5 lunar diameters away.
Elnath is the herald star that will rise between the spires sometime prior to all the Major Lunar Standstill (MLS) moon rise-thru-the-spires events to come at Chimney Rock National Monument, the only natural indicator in the world for the Major Lunar Standstill, an event that occurs every 18.6 years and will be observable from the high mesa starting in fall of 2023.
You will see Elnath at 8:30 at night while it is amongst the stars. Learning the stars around the Major Lunar Standstill position is an important aspect of the whole 3-year season. Constellations Taurus, Gemini, Orion, and Auriga, as well as the star Elnath are important to learn if you want to be a knowledgeable MLS savvy naked eye astronomer.
The following night, Wednesday, April 6, the moon will move about 12 degrees further to the east (prograde motion) and also be closer to a moon rise-thru-the-spires declination. Next year during April, it will be almost a moon rise-thru-the-spires event. However, it will rise about 8:30 in the morning and most likely will be invisible due to the crescent phase, low lumens, and the atmosphere being illuminated by the sun.
Chimney Rock Interpretive Association’s Major Lunar Standstill Committee continues to observe and track celestial events to provide accurate program dates for the special viewings of the moon rising through the twin sandstone spires.
For more information on the MLS and upcoming MLS Special Programs, Astronomy Programs and Night Sky viewing events with the San Juan Stargazers, naked eye astronomy, and archeoastronomy, please visit chimneyrockco.org.