The features of the akakū

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According to the Hawaiian-English dictionaries, this is the definition o this type of rainbow:[1]

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Pukui/Elbert:  n., The phenomenon known as the Specter of the Brocken, seen at Haleakalā Crater. Literally, rainbow apparition.[2]

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Primary trait:              A faint rainbow 

Secondary trait:         A circular rainbow

                                  A rainbow that appears atop high mountains

                                   

An akakū (na Mike7777777 | Dreamstime.com)

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Sometimes, at the top of Haleakalā, mist and/or clouds enter the crater. If a person is standing at an appropriate place on the edge of the crater, it is possible to his/her reflection within the mist or cloud on the opposite side of the crater. Surrounding the reflection of the person is the akakū rainbow. This is similar to a Luakālai in terms of the order of colors. Namely, white is in the center, followed by blue, green, yellow, and red. Haleakalā is one specific place that this has been observed and photographed.

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The English name for this phenomenon is the Spectre of Brocken, since it is seen at the top of the mountain called Brocken in the mountain range of Harz in Germany. It is also seen atop other tall mountains around the world.[3]

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The strata that the akakū appear

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Since the akakū appears at the top of Haleakalā, this falls within the lewa nuʻu strata.

 

The times that the akakū appear

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The word akakū, it is a combination of aka and kū. Therefore, the meaning of akakū is the standing of the reflection (or likeness) of a person. Oneʻs reflection is an important thing, in ancient times, some Hawaiians believed that the spirit of a person is contained in his/her reflection.[4] Therefore, for the Hawaiian, seeing oneʻs reflection at the center of a rainbow at the top of a sacred mountain like Haleakalā is a truly supernatural experience.

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Seeing the akakū rainbow is somewhat rare and was not found in any of the analyzed stories for this project. However, it was found in a song about the island of Maui that was performed on the famous Hawaiian language program "Ka Leo Hawaiʻi". One of the stanzas begins as follows:

 

“He ʻoiaʻiʻo nō ke akakū ānuenue,

ma Haleakalā ka mauna kaulana....” [5]

 

There are many things about Maui that the composer could have chosen and it is interesting that the akakū was significant enough to weave into this song. It is possible that because the akakū is rare, that there were those folks who didn't believe in itʻs existence. Perhaps this is the reason that the first line “He ʻoiaʻiʻo nō ke akakū ānuenue,”  translates to the akakū rainbow is indeed a true thing.

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From the western scientific perspective, the spectre of Brocken is not a supernatural thing, it simply obeys the laws of physics. From that perspective there are 4 requirements for the formation of the spectre of Brocken:[6]

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• The sun must be at a low angle

• A cloud or mist must be present on the mountain

• The must be behind the observer 

• The observer must be standing at an elevated location

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Another English name for the spectre of Brocken is the Glory. The exact scientific reason that the Glory (akakū) appears is not well understood. However, the scientific community does have some theories, they continue to research this type of rainbow. According to one researcher, the Glory is not a full circular rainbow, because the angular diameter of the full rainbow circle is 84 degrees, whereas the angular diameter of the Glory is 20 degrees or less. The existence of the Glory cannot be explained by geometry alone, diffraction must also be considered.[7]​

 

The geometry of the akakū rainbow

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Like other rainbows, when the light rays enter the suspended water drops, they are refracted due to the density of the water. The density of water being larger than that of air. As a result of being refracted inside the water drop, the white light is separated into the 7 rainbow colors. At the back of the water drop each color is reflected back to the front of the drop, and is refracted again as they depart the drop. For the akakū, the light colors are diffracted which forms a virtual lens. Because of this, the colors are collected at the virtual focus point of the lens into a circle behind the water drop forming the akakū.[8]

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The signs/omens of the akakū

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In the analyzed sources for this project, no signs/omens were found for the akakū rainbow. However, as mentioned above, for the Hawaiian, seeing an akakū is a blessing and a reflection of oneʻs spirit.[9]

 

[1] Wehewehe Wikiwiki. n.d.. Ke Kulanui o Hawaiʻi ma Hilo. https://hilo.hawaii.edu/wehe/.

[2] k.l.

[3] Atmospheric Optics. n.d. Brocken Spectre. Accessed October 30, 2023. https://atoptics.co.uk/blog/brocken-spectre/.

[4] Mary K. Pukui, E.W. Haertig, C.A Lee. 1972. Nānā i ke Kumu. Vol. 1. 2 vols. Honolulu: Hui Hānai. Vol 1: 10.

[5] Hanalei Machado. Ua nīnauele ʻia e Kauanoe Kimura. 1973. "HV24.21." Ka Leo Hawaiʻi. (Pepeluali 6).

[6] Atmospheric Optics. n.d. Brocken Spectre. Accessed October 30, 2023. https://atoptics.co.uk/blog/brocken-spectre/.

[7] He manaʻo i hoʻoloa ʻia. E nānā ʻia ka papa wehewehe huaʻōlelo.

[8] Physics.stackexchange.com/users/63097/diracology. n.d. What is the explanation of the glory (optical phenomenon)? Accessed Nowemapa 1, 2023. https://physics.stackexchange.com/questions/256636/what-is-the-explanation-of-the-glory-optical-phenomenon.

   He manaʻo i hoʻolaulā ʻia. E nānā ʻia ka papa wehewehe huaʻōlelo.

[9] Mary K. Pukui, E.W. Haertig, C.A Lee. 1972. Nānā i ke Kumu. Vol. 1. 2 vols. Honolulu: Hui Hānai. Vol 1: 10.