Full Moon – June 2024

In a few days we will have the summer solstice and the beginning of astronomical summer. Two days later, there will be a full June moon, commonly called the Strawberry Moon. However, this year it is not only the name that should catch our attention, but also how the full moon will behave.

Of course, this is not about any unusual visual effects, although such associations may arise. This time, the moon, although full, will not light up the Polish sky to the extent that it usually does when its disk is completely illuminated by the sun – hence the term full moon. Why? This has to do with the Moon’s orbit around the Earth and the fact that the summer solstice occurs two days earlier. The name itself does not need explanation, everyone knows what strawberry is now.

Full moon in June 2024

The summer solstice is the moment when the sun spends the longest time of the year above the horizon and is slightly hidden below it. There is so little in Poland that we do not have an astronomical night from the end of May to the end of July. Above the horizon in the north from sunset to sunrise there is a bright glow, as in other months it occurs before and after sunset. Therefore, June nights favor late-night activity, and it is unfortunate that the traditional holiday season only begins after the summer solstice.

The 2018 full strawberry moon as seen from near the ESO (European Southern Observatory) center on the outskirts of Munich. (ESO/B. Horalik)

If the Sun is visible in our sky for a long time at the summer solstice, the Moon should be visible for a much shorter period of time at the Full Moon, because it rises at sunset and sets at sunrise, being exactly on the opposite side of the Sun. Sky to sun.

On the night of June 21-22, which will be the full Strawberry Moon, the moon will rise at 9:21 pm in the southeast direction and set at 3:41 am, and can be seen in the southwest direction. These are the opening hours in Warsaw, but for other cities in Poland they will be slightly different.

And so it will already be on June 22, two days after the summer solstice on June 20, when the full Strawberry Moon will occur – in Warsaw, for example, it will be exactly on June 22, 2024 at 3:07, i.e. Tonight from the 21st to the 22nd will be the night of the full moon. In addition, our natural satellite will be moving in a very low orbit that night, so that when it ascends toward the south, it will be only about 9 degrees above the horizon, exactly in the constellation Sagittarius (the center of the Milky Way). in a close direction). This will also be the lowest position of the Strawberry Moon in the sky in years.

Not everyone will be able to enjoy the Strawberry Moon

The angular elevation of 9 degrees is approximately the angular size of a clenched fist placed vertically and raised in front of you. This means that the city’s tall buildings will easily obscure the full moon even when they are tall. The Moon will also be low enough above the horizon throughout the night that atmospheric refraction and pollution will prevent it from “sparkling” with the glow of a typical full moon. It may be yellowish or even reddish all the time, as is usually the case at sunrise and sunset other days of the year.

The low position of the Strawberry Moon in 2024 will make it appear exceptionally large. This is despite the fact that it will not be a supermoon this time. The distance between the Earth and the Moon will be close to the average value, i.e. 380 thousand kilometers.

The phrase “not everyone will be able to enjoy the Strawberry Moon” is related to the time the moon will spend above the horizon. The further north we go in Poland, the shorter this time becomes. And if you go, for example, to northern Sweden, Finland or Iceland, you will not see the Strawberry Full Moon at all, because it will be hidden below the horizon all the time. However, you will be able to enjoy the white nights, because the sun will be there all day above the horizon.

In turn, in the Southern Hemisphere of the Earth, everything will be the opposite. The night there will be the longest of the year, and the full moon will appear exceptionally high in the sky in some places. Astronomers observing the galactic center on a full moon and on several nearby nights will have little to do, because the moon’s glare will effectively make observations difficult. The Strawberry Moon will be in the sky near the center of the Milky Way.

Why does the moon change its position in the sky so much?

The moon in Poland may be about 9 degrees above the horizon at sunrise, but it can also be about 67 degrees. The elevation change range is up to 58 degrees. In comparison, the Sun changes its maximum altitude at noon by only 47 degrees between the summer and winter solstice. This means that the moon at night can be seen much higher than the sun during the day. From our vantage point, 67 degrees is almost as if it were directly above us.

These changes in the Moon’s position are related to the position of its orbit. It is inclined to the plane of the ecliptic at an angle of 5.15 degrees (this is an average value that changes slightly). The plane of the ecliptic is inclined relative to the plane of the Earth’s equator by 23.5 degrees (the angle of inclination of the Earth’s axis of rotation). And now the most important thing. The Moon and Sun are constantly moving in their orbits relative to the Earth. The Moon takes less than a month to complete one revolution, and the Sun takes one year. Every day, the Moon and Sun are in a different place in their orbit. When the Earth now completes its daily rotation, we will have the impression that the Moon and Sun are moving more or less parallel to the plane of the Earth’s equator.

The relative position of the Moon relative to the Earth and the plane of the ecliptic, i.e. the plane in which the Earth revolves around the Sun (not to scale).

In Poland, the Earth’s equator is inclined to the horizon by about 38 degrees. The Moon at its highest point in its orbit can be 23.5 + 5.15 degrees above or below the Earth’s equator. This is why there are so many inconsistencies in the position of the moon at night. That’s not all, the full Strawberry Moon occurs on different days in June, and this year it will be exceptionally close to the summer solstice. The situation was similar in 2016 and 2005. These differences are related to the change in the relative position of the orbits of the Earth, the Sun and the Moon, which return to approximately the same position every 18.6 years (this is the so-called Saros period that was known to the ancients).

Source: information. Own entry photo: Unsplash/Guzman Barquin