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Tonight's rare "Blue Supermoon" will be the biggest and brightest of the year

On the night of August 30, 2023, the biggest and brightest full moon of the year – the “blue supermoon” – will make its glorious appearance in the night sky. The term “blue supermoon” is not just a poetic label; it captures a rare convergence of three distinct lunar phenomena. 

As explained by Gordon Johnston from NASA’s Solar System Exploration, the upcoming full moon is a merger of a supermoon and a blue moon that is in alignment with the Hindu festival Rakhi Purnima.

Saturn will dance with the supermoon

On August 30th, as the Earth-based longitude shows the moon in perfect opposition to the Sun, it will light up the night at 9:36 PM EDT. 

The ringed planet Saturn, a few days from its brightest stance for the year, will gracefully accompany our rare blue supermoon. 

Observers can look for Saturn five degrees to the upper right of the Moon as evening twilight ceases at 8:42 PM. The duo will then appear to dance, with Saturn swinging clockwise around the Moon throughout the evening, according to NASA.

What makes this blue moon super?

But why is this moon termed “super”? The supermoon phenomenon refers to the moon’s closeness to Earth during its full phase, making it appear more substantial and brighter. 

Various publications have different criteria for designating a moon as “super,” but both of August 2023’s full moons meet these requirements.

Second full moon of the month

Diving into the “blue” of the blue supermoon, it’s not about the color. Instead, it references this being the second full moon of August. 

This terminology can be traced back to a 1946 Sky & Telescope magazine definition. Intriguingly, the more aged definition from the 1500s designated the third full moon of a four-moon season as the Blue Moon. 

By that criteria, the blue status would belong to the full moon of August 2024. For those curious about witnessing a truly blue-tinted moon, history did record such a spectacle, which can be discovered in-depth on NASA’s site.

Rakhi Purnima

Synced with this lunar event is Rakhi Purnima or Raksha Bandhan, a Hindu festival celebrating the unbreakable bond between siblings. The ritual involves sisters tying a rakhi (a cotton bracelet) around their brothers’ wrists and receiving gifts in return. This act symbolizes the enduring bond and mutual protection between them.

For those who follow traditional solar and lunar calendars, this full moon signifies various important timings. In the Chinese calendar, it marks the middle of the seventh month, while in the Islamic calendar, it’s Safar. 

Jewish observers will note this full moon during Elul, a significant time of introspection and preparation for the forthcoming High Holy Days of Rosh Hashanah and Yom Kippur.

While celestial attire is recommended for full moon viewing, it’s also a great time to cherish family ties, release resentments, and wish for a prosperous year ahead.

Upcoming lunar events

Looking forward as summer transitions into fall, the periods of daylight will decrease rapidly, reaching a turning point at the autumn equinox. 

No significant meteor showers are anticipated in this lunar cycle, but there will be other starry sights. The evening sky of August 30 will showcase Vega, a luminary of the Summer Triangle and one of the brightest in our sky, shining from a distance of 25 light-years away.

August’s second full moon stands out among 2023’s lunar events. It’s not only the third supermoon of the year but also the closest. At a mere 222,043 miles (357,344 kilometers) from Earth, it trumps even the August 1 full moon by a slim margin of 115 miles.

On September 29, be on the lookout for the Harvest Moon, which will be the final supermoon of 2023.

More about the Harvest Moon

August’s Harvest Moon holds special significance in various cultures due to its association with the harvest season. Here are some pieces of folklore and traditions surrounding the Harvest Moon:

Bright nights

The Harvest Moon rises at roughly the same time for several nights in a row, which means that there is no prolonged darkness between sunset and moonrise. 

This phenomenon provided farmers with extended periods of light, allowing them to work late into the evening to harvest their crops.

Symbol of abundance

In many cultures, the Harvest Moon is seen as a symbol of abundance, prosperity, and completion. It’s a time to celebrate the bounty of the earth and to give thanks for the food that will sustain people through the winter.


Many cultures hold festivals or celebrations during the time of the Harvest Moon. For instance, in East Asia, the Mid-Autumn Festival (or Moon Festival) is celebrated with mooncakes, lanterns, and family gatherings.


The bright and large appearance of the Harvest Moon has also given it romantic connotations. In literature and popular culture, it’s often depicted as a perfect backdrop for lovers, symbolizing warmth and hope.

The unexplained

Full moons have often been linked in folklore to strange or unexplained behavior, both in humans and animals. Some believe that full moons can lead to more erratic behavior, though scientific evidence is limited.

More about blue moons

A “blue moon” is a term that has historical, cultural, and astronomical significance. Let me break down the various aspects of the concept:


The older definition of a blue moon is the third of four full moons in a single season. Typically, there are only three full moons in each season, but occasionally there’s a fourth. When this happens, the third is termed a “blue moon.”

Most people today understand the term “blue moon” to mean the second of two full moons in a calendar month with two full moons. As mentioned above, this understanding gained popularity due to an error in an article in “Sky & Telescope” magazine in 1946. This definition became widespread especially after it was used in the popular radio program “StarDate” in the 1980s and then again in 1999 on the Trivial Pursuit game.


Blue moons (by the modern definition) occur approximately once every 2.7 years. This is because the lunar month (the time it takes for the moon to cycle through all of its phases) is about 29.5 days, while most calendar months are longer.


The term “blue moon” has nothing to do with the moon’s actual color. However, on very rare occasions, the moon can appear blue in color, usually due to atmospheric conditions.

For instance, if there have been volcanic eruptions or forest fires that release particles into the atmosphere, these particles can scatter red light and make the moon appear blue.


The term has been in use for hundreds of years and evolved over time. The phrase “once in a blue moon” to indicate a rare event dates back at least 400 years.

“Blue Moon” is a classic song written by Richard Rodgers and Lorenz Hart in 1934. Numerous artists have covered it, making it a staple in American music.

Astronomical details

The moon’s cycle from new moon to new moon, called a synodic month, is about 29.5 days. Our calendar months (except February) are longer than this, which is why it’s possible to fit two full moons in one month.

Other moons

The term “blue moon” is just one of many that describe various full moon phenomena. Others include:

Harvest Moon: The full moon closest to the autumn equinox.

Supermoon: When the full moon occurs at the same time the moon is nearest Earth in its elliptical orbit, making it appear larger.

Blood Moon: Refers to the red appearance the moon takes on during a total lunar eclipse.

Remember, irrespective of the definition or the rarity, a blue moon is still just a full moon in astronomical terms, and it doesn’t have any particular physical significance. It’s the cultural and historical aspects that make it special.

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