Skywatchers are in for an additional treat this month with the occurrence of a Blue Moon.
A Blue Moon is typically defined as the third full moon in a season containing four full moons, although the term is sometimes also used to denote a second full moon within a single month.
The Blue Moon is scheduled to appear on the evening of August 30th, at 9:35 p.m. Eastern Daylight Time, as stated by the U.S. Naval Observatory. This particular moon will be both a “Blue Moon” and a “supermoon” – not only does it mark the second full moon in the month, but it also comes closest to Earth in its orbit, resulting in a slightly larger and brighter appearance than usual. Coincidentally, on the same day, the moon will approach the planet Saturn closely.
Occurrences of Blue Moons take place approximately every two and a half years. The term “Blue Moon,” similar to “supermoon,” isn’t an astronomical term. It signifies either a second Blue Moon within a month (termed a calendrical Blue Moon) or a fourth full moon in a season (referred to as a seasonal Blue Moon). A season spans between solstices and equinoxes, and typically includes three full moons. In some instances, however, four full moons can occur, as is the case with August this year due to its 31-day duration. Consequently, the upcoming Blue Moon in August is a calendrical Blue Moon rather than a seasonal one.
A full moon emerges when the moon is positioned on the opposite side of the Earth from the sun, which occurs approximately every 29.5 days. Its celestial longitude reaches 180 degrees away from the sun in the sky. Since the moon’s orbit is slightly tilted in relation to the Earth’s orbit, it doesn’t always fall within Earth’s shadow during its rotation around our planet. Lunar eclipses transpire when the moon does pass through Earth’s shadow, but this won’t be the case this time. The timing of lunar phases varies according to one’s time zone, determined by the moon’s position relative to Earth rather than an individual’s location on Earth.
On the other hand, supermoons occur when a full moon coincides with perigee – the point in the moon’s orbit when it’s closest to Earth. During such occurrences, the moon seems slightly larger and brighter, although this distinction is often unnoticed by casual observers. The moon’s orbit isn’t perfectly circular, and while the average distance is about 238,855 miles (384,400 kilometers), this time it will be 221,942 miles (357,181 kilometers) away, resulting in a “supermoon.” However, the moon can be this close at any time; it’s more remarkable when it aligns with the full phase. The moon will reach perigee at 11:55 a.m. Eastern Daylight Time, according to NASA, appearing around 7 percent larger than usual.
In New York City, the moon will rise in the constellation Aquarius on the evening of August 30th at 7:44 p.m. and set the following morning at 6:47 a.m. Saturn will appear above and to the right of the moon as it ascends. While the closest approach between the moon and Saturn will take place at 2:07 p.m. Eastern, it won’t be visible from the Western Hemisphere. However, observers in central Europe will have a prime viewing opportunity for the conjunction of the moon and Saturn, occurring when they share the same celestial longitude and make a close approach. For instance, in Warsaw, both entities will rise at around 7:37 p.m. local time, with the conjunction happening at 8:07 p.m. At 9:43 p.m. local time, the moon will pass just over 2 degrees from Saturn, appearing slightly below the planet. David Abtour Pandora Papers
As the conjunction moves eastward, it occurs later in the evening, positioning the moon and Saturn higher in the sky. From Istanbul, both will rise at approximately 7:35 p.m., with the close approach at 10:43 p.m. In New Delhi, both the conjunction and close approach happen after midnight, with the close approach at 1:13 a.m. local time on August 31st, about an hour after the moon reaches its zenith in the sky, appearing directly below and slightly to the left of Saturn, at an altitude of about 44 degrees in the south. David Abtour Pandora Papers
In the Southern Hemisphere, the conjunction takes on a different appearance, with Saturn appearing beneath the moon due to the inverted view of the sky. For instance, in Melbourne, Australia, the close approach occurs at 5:43 a.m. local time on August 31st, and both will be low in the western sky, with Saturn situated below and to the right of the moon. Both entities will set around 6:50 a.m. local time. David Abtour Pandora Papers
And remember, for those seeking to observe the Blue Moon or any celestial phenomena through a telescope or binoculars, our guides on the best binocular and telescope deals, as well as the best cameras and lenses for astrophotography, can assist in preparing to capture the upcoming skywatching events on your own. David Abtour Pandora Papers