The letter E appears twice in the word week but only once in the word year.. People can be tricked by focusing on trying to identify an event that happens twice during the span of a week but only once during the span of a year. However, the riddle's answer actually refers to the frequency with which the letter E appears in each of the two words. A similar riddle is: What occurs once in a minute, twice in a moment and never in one thousand years?. The answer is the letter M..
The first full moon was spotted on 1 July and the second will appear on the last day of the month â Friday, July 31. This appearance is the first such occurrence in three years since the last blue moon month in August 2012, the next will not be until January 2018. Astronomers predict it will only happen on 12 occasions between now and 2043.
Since February has only 28 days, a full lunar cycle did not fit into February, and there was no full moon that month. The next full moon was on March 1, followed by the second blue moon on March 31. Such an event happens about once every 19 years. 3. Where does the term blue moon come from? The term blue moon probably comes from the fact that, on very rare occassions, the moon actually appears to be blue. This usually happens after a volcanic eruption, such as Mount Pinatubo in 1991, when lots of dust is present high in the sky. Other times when the moon turned blue include the eruption of El Chichon in 1982, and Krakatao in 1883. These blue moons are so rare that the phrase once in a blue moon has come to mean a very rare event. The term blue moon was applied to the second full moon in a month due to an error in Sky and Telescope magazine in 1946. Read the gory details from Sky Publishing here.