The moon goes through a cycle of eight phases, taking roughly 29.53 days to complete. These phases are determined by the moon’s position relative to the sun and Earth. A full moon occurs when the moon is positioned directly opposite the sun, with the Earth in between. This alignment allows the entire face of the moon to be illuminated by the sun, resulting in the bright, round orb we associate with a full moon. Tonight, February 21st, 2025, the moon is in a Waning Crescent phase, meaning it is not a full moon.
The Waning Crescent moon is visible just before sunrise in the western sky. Its illumination is decreasing daily, shrinking towards the next New Moon. During this phase, from Earth’s perspective, the moon is moving closer to the sun. We see primarily the night side of the moon, with only a sliver of the edge illuminated by sunlight.
The Waning Crescent moon on February 21st has an illumination of 43%. This percentage represents how much of the moon’s surface is lit by the sun. Lunar illumination changes constantly, sometimes varying by as much as 10% per day. On this day, the moon is 22.82 days old, counting from the last New Moon.
The current moon sign is Sagittarius, at 11.94 degrees within the sign. The moon’s position within the zodiac constellations changes approximately every 2 to 2.5 days as it journeys across the sky. While the moon’s phase influences its brightness, its zodiac sign is associated with astrological interpretations. The four primary moon phases are the Full Moon, New Moon, First Quarter, and Last Quarter. The four minor phases are Waxing Crescent, Waxing Gibbous, Waning Gibbous, and Waning Crescent. Each phase offers unique viewing opportunities for skywatchers. During the Waning Crescent, the diminishing light can make it easier to observe the moon’s surface features, such as craters and mountains, through binoculars or a telescope. Their long shadows become more pronounced along the terminator, the line dividing the illuminated and dark sides of the moon.
