Skywatch: Hawaii’s royal historian provided calendar source

Kekaomakali‘i arcs overhead, rising on the Hikina horizon — east — and moving toward the Komohana horizon — west. Within the bailer-­shaped celestial image lies Hokulei (Capella); Nanamua and Nanahope (Castor and Pollux); Puana (Procyon); ‘A‘a (Sirius); and Keali‘iokonaikalewa (Canopus, chief of the southern skies).

Seeing the first of the four star families is a reminder that a new year has begun. From about 2:30 a.m. until sunrise, Hanaiakamalama (the Southern Cross) can be seen arcing slowly across the southern horizon.

David Malo, Hawaii’s first royal historian and one of the first 25 young male Hawaiian students to attend Lahainaluna Seminary in 1831, provided the first primary source of information for the keeping of the Hawaiian calendar. A Kona resident, Malo grew up in an era when traditional Hawaiian religion and customs were still practiced.

According to Malo, there were two seasons, kau (summer) and hooilo (winter), which were divided into six-month cycles. The names of the 12 months and the particular 30-day lunar period that it pertained to differed from island to island. The months referenced here are for Hawaii island.

The summer season began in May and ran through October. The months were Ikiiki (May), Ka‘aona (June), Hinaia‘ele‘ele (July), Mahoe­mua (August), Mahoehope (September) and ‘Ikuwa (October). The winter season began in November and ran through April. The months were Welehu (November), Makali‘i (December), Ka‘elo (January), Kaulua (February), Nana (March) and Welo (April).

The monthly Hawaiian lunar calendar had 30 nights, called po. Because this was a visual calendar, on certain months, the last po might have been deliberately left off.

Twelve months of 29 to 30 po would have meant that over one year the calendar would have drifted 10.75 days as compared to the Gregorian calendar. To calibrate this difference in drift so that the names matched the observable night sky, every three years the kahuna kilo hoku (one who is skilled at astronomical observations) would need to intercalate the calendar by inserting an additional month. We have no documentation of this process; however, we know that this was a practice in the South Pacific.

Featured Mauna Kea observation

Astronomers using the Gemini North Telescope on Mauna Kea are working to further study the black hole at the center of our galaxy and continue this Nobel Prize-winning research.

The galactic center of the Milky Way is a very active place, and most of this activity is centered around an object known as Sagittarius A*, often shortened to Sgr A*.

In 2020 the Nobel Prize in physics was partially awarded to the teams of astronomers that verified that the object Sgr A* is a supermassive black hole; most of this research was conducted on Mauna Kea as well.

Now, astronomers continue to utilize the Mauna Kea observatories to further study the nature of Sgr A* and the overall environment at the center of our galaxy. Recent research has analyzed the precise motions of the stars in the galactic center indicating that a majority of the mass at the center of the galaxy is due to the supermassive black hole.

These findings have important implications for how our galaxy formed, how our galaxy can keep itself together and what the future holds for the Milky Way. Read more about this research here: 808ne.ws/SgrA.

Evening observations

Immediately after sunset, careful observers will be able to spot the bright planet Jupiter. As one of the brightest objects in the sky, Jupiter will be one of the first objects to appear through dusk. However, the planet will set before 8 p.m. so people who want to catch sight of the planet will need to look immediately after sunset.

Amid the starline of Kekaomakali‘i, a multitude of famous astronomical objects can be easily spotted. Beneath the three brilliant stars of Kaheiheionakeiki (Orion), we can see a few stars that are often considered to be Orion’s sword. Behind these stars, observers will find a faint cloud-like fuzziness that is the glow from the Orion Nebula (M42), a large stellar nursery and the closest region of massive star formation to Earth.

To the northwest of Kaheiheionakeiki is the open star cluster of Makali‘i, (Pleiades or the Seven Sisters). This 75 million- to 150 million-year-old star cluster contains more than a thousand stars of all different types.

Open clusters like Makali‘i act as stellar laboratories and allow astronomers to study how different varieties of stars live and die.

To see what is left over after a massive star dies, we don’t need to look far. Just south of the shape of Hokulei, observers can find the Crab Nebula with a good telescope. This stunning nebula is the result of a supernova explosion that was observed in the year 1054 AD.

Supernovae occur when the largest and brightest stars run out of nuclear fuel and the hydrostatic equilibrium of the star is no longer maintained. The core of the star collapses and rebounds, creating enough energy that the star will outshine its galaxy.

The 1054 AD supernova that created the Crab Nebula was said to be so bright that it was observed in daylight for a few months. Hence, in this little section of the sky, observers can see where new stars are being born, where a family of stars is interacting and where one massive star has died.

Morning observations

As February proceeds, the sun will rise earlier and earlier — starting the month at 7:08 a.m. and ending at 6:52 a.m. Dawn will color the sky between 6:30 and 6:45 a.m.

Around 6 a.m., stargazers will be able to spot the three terrestrial planets of Mars, Venus and Mercury grouped together. The most noticeable planet will be Venus, which will likely be the brightest object in the sky at this time. To the south of Venus will be the red planet Mars, which stands out with a distinctive color. Closer to the horizon, careful observers will also be able to spot the planet Mercury.

Throughout February, these three planets will dance around each other as Mars subtly moves toward the east and Venus and Mercury climb higher in the sky.

The planets have been notable in our sky for centuries as they appear to move against the background of the stars when we observe them across multiple nights. This shift against the background of the stars is especially noticeable with the inner planets of the solar system; since they are closer to the sun, they move faster in their orbits.

In late February, the faint planet Saturn will join Venus, Mercury and Mars in their celestial dance. Saturn and Mercury will have a quick conjunction in early March.

February 2022 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.