We present you the April 2021 astronomy calendar. Astronomy is the foundation upon which astrology can operate. Actually, astrology and astronomy were treated together, under the Latin name of astrologia, being separated only by the Western 17th century philosophy. For sure: a good astrologer needs to study astronomy.
Monday, April 12th: New Moon
The New Moon is when the Sun and Moon are aligned, with the Sun and Earth on opposite sides of the Moon. The new moon is the first lunar phase, when the Moon and Sun have the same ecliptic longitude. At this phase, the lunar disk is not visible to the unaided eye, except when silhouetted during a solar eclipse. This is the best time of the month to observe faint objects such as galaxies and star clusters because there is no moonlight to interfere.
Thursday, 22nd, Friday, 23rd April: Lyrids Meteor Shower
The April Lyrids are a meteor shower lasting from April 16 to April 26 each year (this year, on 22nd-23rd April). The radiant of the meteor shower is located in the constellation Lyra, near this constellation’s brightest star, Alpha Lyrae (proper name Vega).
The source of the meteor shower is particles of dust shed by the long-period Comet C/1861 G1 Thatcher. The April Lyrids are the strongest annual shower of meteors from debris of a long-period comet, mainly because as far as other intermediate long-period comets go (200–10 000 years), this one has a relatively short orbital period of about 415 years. The Lyrids have been observed and reported since 687 BC; no other modern shower has been recorded as far back in time.
Best viewing will be from a dark location after midnight.
Tuesday, April 27th: Full Moon and Supermoon
The full moon is the lunar phase when the Moon appears fully illuminated from Earth’s perspective. This takes place when Earth is located directly between the Sun and the Moon. More exactly, the ecliptic longitudes of the Sun and Moon differ by 180°). This means that the lunar hemisphere facing Earth – the near side –appears as a circular disk (being completely sunlit), while the far side is dark.
April full moon was known by early Native American tribes as the Full Pink Moon, because it marked the appearance of the moss pink, or wild ground phlox, which is one of the first spring flowers. Some coastal tribes called it the Full Fish Moon, because this was the time that the shad swam upstream to spawn. This moon has also been known as the Sprouting Grass Moon, the Growing Moon, the Egg Moon or the Goose-Egg Moon and the Ducks Moon.
According to the original definition of supermoon – coined by the American astrologer Richard Nolle in 1979 – this is „a new or full moon which occurs with the Moon at or near (within 90% of) its closest approach to Earth in a given orbit (perigee). In short, Earth, Moon and Sun are all in a line, with Moon in its nearest approach to Earth“. This closest approach to the Earth results in a slightly larger-than-usual apparent size of the lunar disk as viewed from Earth.