Other than the sun, the moon is the most striking celestial body visible from Earth. It orbits the globe at a distance of around 384,000 kilometers and sometimes comes a little closer to the blue planet, sometimes it is further away. This is due to the elliptical orbit shape, which is generally the rule for celestial bodies in a gravitational field. Perfect circular orbits, on the other hand, are rare. All orbital shapes are based on the so-called conservation of angular momentum, a conserved quantity in physics.
The ideal shape of the Earth’s orbital ellipse is influenced to a greater or lesser extent by disturbing effects. These include, for example, the flattening of the Earth, the distance-dependent gravitational effects of the sun and planets and an inhomogeneous mass distribution in the Earth’s interior. Deep beneath the earth’s crust, the earth’s mass is unevenly distributed, so that our planet’s gravitational pull is slightly stronger in some regions than in others.
With a diameter of 3,476 kilometers, the Earth’s satellite is the fifth largest of the 205 moons that all of the planets in our solar system have. Only three of Jupiter’s four large moons and Titan, a moon of Saturn, are larger. The earth’s companion has significantly less mass than our blue planet and only exerts a sixth of the Earth’s gravitational pull. If a person weighing 60 kilograms stood on the moon, he would feel as if he weighed 10 kilograms and could therefore jump much higher and further.
The same side of the moon can always be seen from the Earth’s surface. This is because the celestial body rotates exactly once while it orbits our planet once. The Soviet lunar probe Lunik III sent the first images of the back in 1959, but people first saw the side facing away from Earth with their own eyes when the crew of Apollo 8 orbited the Earth’s companion at Christmas 1968.
The moon can sometimes be seen as a crescent, sometimes only half and sometimes as a luminous, complete disk. “The moon is called a full moon when its side facing the earth is opposite the sun and is therefore fully illuminated,” explains Dr. Manfred Gaida, astronomer and research associate at the German Aerospace Center (DLR) in Bonn-Oberkassel. “The moon is usually slightly above or below the plane in which the Earth orbits the sun.” A full moon is only possible at night because the moon and the sun must be on opposite sides of the globe. Therefore, the full moon rises on the horizon exactly as the sun sets on the other side.
What is the name of the full moon?
In many cultures, each full moon of the year has a different name. This was also the case in Central Europe for a long time, which is why different names are still used today.
The list includes the Old German names and the names given to the full moon by the North American Algonquian tribe.
How often does a full moon occur?
The so-called lunar phases have determined people’s lives for many centuries. For example, they formed the basis for agricultural activities and for dividing the year into months. The full moon is also said to have special powers. For example, Christmas trees cut during the full moon are said to retain their needles for a very long time.
The full moon is one of the four phases of the moon. The solar star and the earth’s companions are in opposition to each other. So when viewed from the Earth’s surface, they are in opposite directions. In exactly this constellation, the side of the satellite facing us is completely illuminated by the sun and reaches its maximum brightness. When the sky is clear, a high full moon, which often occurs in winter, can even illuminate the earth so brightly that colors can be perceived by the human eye. The brightness is up to 0.25 lux, around 250 times that of a starry new moon night.
Full moon calendar: When is the next full moon?
During its orbit around the Earth, different amounts of our celestial companion can be seen. Depending on the constellation, there is a full or new moon. Phenomena such as the supermoon can also occasionally be observed. So-called lunar calendars provide an overview of the phases of the moon.
Some people are interested in knowing when a fully, brightly lit disk of the moon can be seen in the sky just out of curiosity. Others base everyday tasks such as cutting hair or certain gardening tasks on the phases of the moon. Many people also believe that they sleep worse during full moon times.
According to the lunar calendar, the dates for 2024 are on the following days:
The times correspond to the currently valid Central European Time or Central European Summer Time.
How often is there a full moon?
As a rule, the phenomenon only occurs once a month. “The full moon phase repeats itself around every 29.5 days,” explains Dr. Manfred Gaida from DLR. The period from one full moon to the next is called the synodic orbital period of the Earth’s satellite. “This orbital period plays a role in all calendars that are not purely solar calendars. An example is the Gregorian calendar, in which the movement of the moon is relevant for determining the annual date of Easter.”
How many days are there between two full moons?
The satellite orbits our planet in an elliptical orbit and returns to its original position in relation to the solar star after around 29.5 days (more precisely: 29 days, 12 hours and 43 minutes). Astronomers also refer to the changing period of time for this orbit as the lunation or synodic period.
The lunation period is usually measured from one new moon to the next. It can differ by more than three hours compared to the previous lunar path, and differences of over 13 hours can occur over a decade. The average value for a lunation is 29.53 days and is also called a synodic month. The full moon also returns approximately every 29.53 days.
The phases of the moon occur regardless of the distance of the satellite in its orbit to the Earth. “Because the moon moves around the earth in a slightly elliptical orbit, the distance between the earth and the moon varies. More precisely, between the centers of both celestial bodies,” explains Dr. Manfred Gaida from DLR. “This means that over the course of a so-called anomalistic month of 27.5 days, the moon is sometimes closer and sometimes further away from us.” The minimum is 356,400 kilometers and the maximum is 406,700 kilometers. “If the full moon phase falls during the period in which the distance becomes minimal, we have been talking about a supermoon for some time, as the apparent size and brightness of the Earth’s satellite then reach maximum values,” the expert describes the phenomenon.
However, the difference between the values of a supermoon and those of a moon far from Earth can hardly be seen with the naked eye. “As far as size is concerned, it’s like looking at a one- and a two-euro coin one behind the other on a white wall 2.70 meters away and trying to tell the difference,” says Dr. Manfred Gaida is a clear example. The difference is hardly noticeable to observers with the naked eye. Only photos reveal the fluctuations in the diameter of the full moon.
This text has been updated.
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