The next Blue Moon is about to grace the dark skies later this month, on the day of Halloween. This will be the second full moon to appear in the month of October. The unusual cosmic appearance is about the take place during the coming weekend on Saturday, October 31.
The Blue Moon does not really mean that the moon will appear in blue colour or have a bluish hue, as the name might suggest. Instead, the lunar event is referred to as a Blue Moon as it will mark the second full moon that appears in the skies during the same month. The second moon of the month is also known as the Hunter’s Moon. We already witnessed the first full moon rise up earlier this month on October 1, known as the Harvest Moon.
According to a report from EarthSky, the full moon might actually carry a slight hue of blue if there are any smoke or dust particles in the environment of a particular size. Such particles in the environment can scatter the red light, and when the moon appears through these particles, it may actually appear blue. It should also be noted that this is only possible when the smoke and dust particles are wider than 900 nanometers. According to TimeAndDate, the moon may also appear blue as a result of volcanic ashes, water droplets in the atmosphere, or some types of clouds. However, the change in colour is extremely rare.
Blue Moons that are blue are incredibly rare and have nothing to do with the calendar or the Moon's phases but are instead a result of atmospheric conditions. The Blue Moons or Hunter's moon are pretty rare and they occur only once in about two and a half years. The last time a Blue Moon was sighted was back in March 2018.
The October Blue Moon will be visible this Saturday on October 31 across different time zones. As far as a Halloween blue moon is concerned, it is far more unusual. According to a report from the Old Farmer’s Almanac, a Halloween Blue Moon only appears once every 18 or 19 years.
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