We offer you the May 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.
Thursday 6th, Friday 7th May: Eta Aquarids Meteor Shower
The Eta Aquarids are a meteor shower associated with Halley’s Comet. The meteors we currently see as members of the Eta Aquariid shower separated from Halley’s Comet hundreds of years ago. The current orbit of Halley’s Comet does not pass close enough to the Earth to be a source of meteoric activity.
The Eta Aquarids get their name because their radiant appears to lie in the constellation Aquarius, near one of the constellation’s brightest stars, Eta Aquarii.
The shower peaks at about a rate of around a meteor per minute, although such rates are rarely seen from northern latitudes due to the low altitude of the radiant. In the Northern Hemisphere, the rate can reach about 30 meteors per hour. Best viewing will be from a dark location after midnight. Meteors will radiate from the constellation Aquarius, but can appear anywhere in the sky.
Tuesday, 11th May: 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.
Monday, 17th May: Mercury at Greatest Eastern Elongation
In astronomy, a planet’s elongation is the angular separation between the Sun and the planet, with Earth as the reference point. The greatest elongation of a given inferior planet (Mercury or Venus) occurs when this planet’s position, in its orbital path around the Sun, is at tangent to the observer on Earth. The planet Mercury reaches greatest eastern elongation of 22 degrees from the Sun. This is the best time to view Mercury since it will be at its highest point above the horizon in the evening sky.
Wednesday, 26th May: 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.
May full moon was known by early Native American tribes as the Full Flower Moon because, in most areas, flowers are abundant during this time. Other names for May Full moon were Green Grass Moon, Root-Food Moon, Milk Moon and Corn Planting 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.
Wednesday, 26th May: Total Lunar Eclipse
A lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow. This can occur only when the Sun, Earth, and Moon are exactly or very closely aligned, with Earth between the other two. A lunar eclipse can occur only on the night of a full moon.
This is the first lunar eclipse in 2021. It is visible in Southenr and Eastern Asia, Australia, much of North America, South America, Pacific, Atlantic, Indian Ocean, Antarctica.