This weekend, residents across the nation will have the opportunity to witness a blue moon, a rare celestial event where two full moons appear in a single month. The term “blue moon” has been used since the 1500s to describe something seemingly impossible, but today it refers to this specific lunar occurrence.
What is a Blue Moon?
A blue moon is the second full moon to appear in a calendar month. This phenomenon happens about seven times every 19 years, or roughly every two to three years, due to the moon’s cycle of 29.5 days, which is slightly shorter than the average month. As a result, some months will have two full moons, with the second being termed a blue moon.
There are two types of blue moons: calendrical and seasonal. A calendrical blue moon occurs when two full moons appear in one month. In contrast, a seasonal blue moon happens when four full moons appear in a three-month season, with the third being the blue moon. The next seasonal blue moon is expected on May 20, 2027.
The Science Behind the Blue Moon
Despite its name, the blue moon will not appear blue. It will maintain its usual silvery white or golden hue. The phrase “the moon is blue” originated from the 1500s, describing something impossible. However, in rare instances, the moon can appear blue if the Earth’s atmosphere contains smoke or dust particles, such as after the 1883 eruption of Indonesia’s Krakatoa volcano.
This weekend’s blue moon will also be a micromoon, meaning it will be near its farthest point from Earth in its orbit, known as the apogee. At this point, the moon is about 252,334 miles from Earth, compared to its average distance of approximately 238,855 miles. While it will be the year’s most distant full micromoon, the difference in size will not be noticeable to the unaided eye.
When to See the Blue Moon
The blue moon will reach its peak at 4:45 a.m. ET on Sunday, just before sunrise. For those in the Americas, Africa, and Europe, the moon will appear fullest on the night of May 30. Meanwhile, residents in Australia, New Zealand, and Asia will see the brightest full moon on the night of May 31.
Dr. Pamela Gay, a senior scientist at the Planetary Science Institute, suggests that this time of year is ideal for capturing photos of the full moon. “When that moon is rising, sometime between 5:30 and 6:30 in your time zone, and the sky is still this beautiful blue, there’s not a lot of weird settings to fuss with, your cellphone will take care of all the details for you,” she said.
Original reporting: El Paso News (HLL/CB) — read the source article.
