We’re still about a month off from Mid-Autumn Festival when we do most of our year’s worth of moon-gazing, but go on — lean your face skyward on 22 August to witness a rare blue moon that only comes ’round once in a… well, you can finish the sentence.
We’re extremely apologetic to be the bearer of news that might prove disappointing, but the blue moon is actually a misnomer on several different fronts. First, it most probably wouldn’t be blue; it’d likely be in the realm of oranges and yellows, unless extraordinary circumstances — say, a volcano eruption — occur. So, not likely.
A blue moon typically — and for the pedants: Erroneously! — refers to a second full moon that rises within a single calendar month, but the upcoming blue moon is, in fact, the only full moon occurring in the month of August 2021. Yet, this weekend’s blue moon is still defined as such, which is accredited to the original definition for what makes a full moon “blue”.
Pulled from the Maine Farmers’ Almanac’s 1937 edition, the term “Blue Moon” was given to the third full moon should a season have four full moons rather than the conventional three. This extra moon-count ups the year’s normal twelve-count to thirteen, which “was considered a very unfortunate circumstance… and it upset the regular arrangement of church festivals. For this reason 13 came to be considered an unlucky number.“
Fortunately, there’s no luck involved if you want to spot this blue moon this Sunday in Hong Kong. As with all full moons — this one would likely just appear a bit bigger; a bit fuller — the best site for moon-gazing is anywhere with a clear patch of sky and anywhere light on light pollution. Perhaps a remote stretch of sand? A patch of grass that’s a little off the beaten path?
Either way, set an alarm for 8:01pm on 22 August, 2021 and aim your gaze towards the (hopefully cloudless!) night sky.