After the shooting stars of the night of San Lorenzo, the sky is putting on another unmissable show: the appointment is for Sunday 22 August with the night of the Blue Moon. see with the color of our satellite, which will remain the same as ever, but only a curiosity of the calendar, defined as the third full moon of a season that hosts four.
An unusual but not rare event, which is repeated approximately every two and a half years: the next will be in 2024.
Brilliant and spectacular, the full moon of August 22 illuminates the sky in the company of the two giant planets, Jupiter and Saturn, which are in the period of maximum visibility. The trio can be observed with the naked eye from all over Italy, weather permitting, and can be admired while parading over Rome and its monuments thanks to the live images of the Virtual Telescope, also transmitted on the Ansa Science & Technology Channel starting from 20.30.
"On average we have one full Moon per month, as our satellite takes 29.5 days, or just under a month, to complete its cycle. For this reason - explains astrophysicist Gianluca Masi, head of the Virtual Telescope - it happens that, from time to time, we have 13 times the full Moon in a year ". And this is how, to indicate this 'extra' moon, the name 'Blue Moon' came into use in the Anglo-Saxon world. In the 1930s, the Maine Peasant Almanac used this term to specifically refer to the third full moon of a season that hosts four. This definition was then misinterpreted in the 1940s by an author of the Sky & Telescope magazine, which has thusended up spreading the definition of Blue Moon as the second full moon in the same month.
That of August 22, 2021 is a real Blue Moon, according to the original meaning of the term: it is the third full moon of this summer 2021, which has already given us two full moons (June 24 and July 24) and still has I have a quarter for September 21st.
"The Moon of 22 August - adds Paolo Volpini of the Italian Amateur Astronomers Union (Uai) - allows even the less experienced to be able to more easily recognize the two giant planets in the sky, Jupiter and Saturn, which in the central hours of the night will culminate in the south : a few days after their opposition, they appear larger and brighter than usual ". To facilitate observation, even without the disturbance of the Moon, the UAI organizes the 'Notti dei Giganti' initiative, with observational evenings throughout Italy scheduled for the 27th,28 and 29 August.
