Skywatch: Think of fall equinox as midpoint of season

Kalupeakawelo, the Kite of Kawelo, is the fourth and final star family to be featured.

We started off the year with Kekaomakali‘i in the winter, Kaiwikuamo‘o in the spring, Manaiakalani in the summer, and now end with Kalupeakawelo for the fall.

The star families are a modern Hawaiian invention that have been used consistently by the voyaging community for 25 years. The concept was developed by college students to create a system for identifying bright stars and constellations that followed a traditional storyline and to demonstrate that culture is not static.

Culture needs to evolve, be relevant and provide opportunities for growth to keep the culture vital and dynamic.

A star family or starline divides the celestial sphere into four quarters. Each quarter follows a season: winter, spring, summer and fall. The starline is a series of bright stars and constellations that have sections in the Northern and Southern hemispheres and follow a traditional Hawaiian story.

Kalupeakawelo, the Kite of Kawelo, is the story of a mythical Hawaiian young man, Kaweloleimakua of the Kawelo clan.

A resident of Kauai, he possesses human qualities that demonstrate a high degree of skill and acumen. As a young man he is noted for his kite-flying skill with which he entangles and cuts the string of other kite flyers around him.

The Kite of Kawelo, the Lupe, is the same constellation as the Great Square of Pegasus, the mythical white winged stallion from Greek mythology who is the son of Poseidon.

The two stars that make up the northern side of the Great Square of Pegasus are Alpheratz and Scheat, rising on the boundary that lies between the houses of ‘Aina and Noio Ko‘olau. The two stars on the southern side of Pegasus are Algenib and Markab, rising on the boundary that lies between the houses of La and ‘Aina Ko‘olau.

Imagine the Great Square of Pegasus as a box-shaped kite with sets of controlling lines running from the corners of the north and south sides of the box. The control line that runs northward from Alpheratz ends at ‘Iwakeli‘i, Cassiopeia, and the control line that runs northward from Scheat ends at Kamo‘i, Cepheus, the mythical king of Aethiopia.

From the southern corners of the Great Square of Pegasus, the star Algenib has a control line that runs southward to the star Archenar in the River Eridanus, and the star Markab has a control line that runs southward and ends at Altair in the constellation Grus, the Crane.

As the kite rises and climbs skyward from the eastern horizon, it is guided overhead with the control lines and directed downward and into the western horizon.

In navigation the pair stars Alpheratz/Algenib and Scheat/Markab are considered meridian pairs.

A meridian pair is composed of any two stars that pass through the celestial meridian at about the same time; drawing an imaginary line through them will indicate the celestial poles, north or south.

In the case of the Great Square of Pegasus, running lines through the edge of the box northward would indicate the north celestial pole and would mark the direction ‘Akau on our star compass.

Featured Mauna Kea discovery

Lithium is one of the simplest elements on the periodic table and is essential in our modern world as a component of rechargeable batteries that power our smartphones, tablets, computers and other devices.

As with all of the atomic elements, lithium’s origins are connected to the stars, and astronomers utilizing the Subaru Telescope are questioning the stellar origin of this essential element.

While it is well accepted that all of the hydrogen in the universe was created with the big bang along with some of the helium of the universe, the rest of the helium was created in the hearts of stars. Lithium was thought to be created through stellar events called novae.

A nova occurs when a white dwarf star steals gases from a companion star and the resulting material causes large explosions of energy off the surface of the white dwarf.

This explosion is less energetic and very different from a Type 1a supernova, as was discussed in last month’s article.

However, the Subaru Telescope’s current observations of recent nova events yielded very low amounts of lithium created, and that finding has led researchers to update their thoughts on the origins of lithium in the universe and look at other celestial events for the creation of this simple but important element.

Special events

Sept. 22 marks the autumnal or fall equinox, when the sun rises exactly east and sets exactly west.

The equinox is often celebrated as the first day of fall; however, it could better be described as the perfect midpoint of fall.

Despite the term “equinox,” this day will not actually have equal parts day time and night time. In Hawaii, Sept. 27 will be the day with the closest amount of equal day and night, with the day lasting 12 hours and 43 seconds. As we approach the winter season, the sun will rise and set in the southern sky, and our days will get shorter.

Evening observations

Throughout September a variety of planets will be visible in the early evening sky.

The brightest planet, Venus, will be near the western horizon after sunset. Venus is the third-brightest object in the sky, after the sun and full moon.

Because Venus is closer than Earth to the sun, the planet will always either set just after the sun sets in the evening or rise before the sun rises in the early morning. Venus is so bright and viewed so close to the horizon that it is often mistaken for a UFO.

The fourth-brightest object in the sky after Venus is the planet Jupiter, which will rise in the eastern sky in the early evening during September.

Jupiter is the largest of the gas giant planets, which are primarily made up of hydrogen and helium gases with no solid rocky surfaces. Looking at Jupiter with a good telescope, you can see the different- colored gas bands in the outer atmosphere of the gas giant.

The light-colored areas are regions where hot gases are rising to the surface of Jupiter’s atmosphere, while the dark-colored areas indicate where colder gases are sinking back to the lower atmosphere.

The colors of Jupiter’s atmosphere indicate the temperature and composition of the gases.

Just west of bright Jupiter will be the fainter planet Saturn. Another gas giant, Saturn is the second-­largest planet in our solar system. Its claim to fame is its immense system of rings.

Immediately after sunset you will be able to catch the faint planet Mercury just above the western horizon. Being the closest planet to the sun, Mercury will always either set immediately after the sun sets or rise immediately before the sun rises.

The best opportunity to spot Mercury will be on Sept. 13, when the planet is at its greatest eastern elongation; on this night Mercury will set just after 7:30 p.m.

In addition to the four planets decorating the early evening view, a spectacular view of our Milky Way galaxy dominates the southern sky during the summer season. The Milky Way band stretches from the northeast and reaches down into the southwest, with the galaxy’s “bulge” dominating the southern sky.

Morning observations

Throughout September, dawn will begin to color the sky around 5:30 a.m., and the sun will rise around 6:15.

In these early morning hours, we will be able to observe the famous shape of Orion, Kaheiheionakeiki, high up in the southern sky. Toward Manu Malanai, the incredibly bright star ‘A‘a, Sirius, will be highly noticeable as the sun rises; it’s the brightest star that can be seen in the twilight sky.

September 2021 Sky Chart by Honolulu Star-Advertiser

The ‘Imiloa Astronomy Center of Hawaii is a center for informal science education at the University of Hawaii at Hilo showcasing astronomy and Hawaiian culture as parallel journeys of human exploration.