On the morning of Oct. 8, Hawaii’s astronomy community woke to some exciting news: UCLA astronomer Andrea Ghez, who has conducted research with the W.M. Keck Observatories for over 25 years, had just been awarded the 2020 Nobel Prize in Physics.
Ghez’s research has centered around the black hole in the center of the Milky Way galaxy, which is known by the name Sagittarius A*. Using the Keck Observatories on Mauna Kea, Ghez has tracked about 20 stars that orbit around the black hole, which is invisible. However, by observing these orbiting stars, Ghez could determine how massive the black hole is.
As her research evolved, she organized a team of astronomers to study the environment around the black hole at the center of our galaxy.
One of those team members is Devin Chu, an astronomer born and raised in Hilo. Chu’s doctoral research focused on a unique star named S0-2 which orbits around Sagittarius A* at relativistic speeds (close to the speed of light). By studying this star, Chu and Ghez were able to test the fundamental physics of relativity, all through observations conducted here in Hawaii.
More information on work done by Ghez and Chu is available at imiloahawaii.org/new-page-2 in the October issue of ‘Imiloa’s Kilolani newsletter.
Makahiki
We are well into the Makahiki season when Hawaiians celebrated the god Lono, who had dominion over agriculture, rainfall, harvest and fertility. This annual season lasted four lunar months from ‘Ikuwa (October) through Ka‘elo (January).
A lot of what we know about it comes from the writings of the Hawaiian primary-source historian David Malo. Born in 1795, Malo was quite familiar with the celebration and religious worship of his people as a youth growing up in Kona. His book, “Mo‘olelo Hawai‘i: Hawaiian Antiquities,” translated in 1898 by Nathaniel B. Emerson, details the authentic Hawaiian cultural and religious practices of his people.
The start of the Makahiki season in October began on the first day of the new lunar cycle. During this time the paramount god Ku was put aside for four lunar months, and the strict kapu system that ruled over the lives of Hawaiians was relaxed and replaced with local athletic competitions.
The Makahiki season was coordinated with the rising of Makali‘i, the Pleiades, on the eastern horizon after sunset. People living on Hawaii’s westernmost coasts, like Kona, could not see Makali‘i as the constellation was obscured by the mountains of Hualalai and Maunaloa; they had to use another celestial marker to identify the start of the Makahiki season.
At the beginning of Makahiki season, as Makali‘i is rising on the eastern horizon, to the north of it is the celestial “W,” ‘Iwakeli‘i, or Cassiopeia. Opposite ‘Iwakeli‘i and setting on the western horizon is Nahiku, the Big Dipper. These two constellations, Nahiku and ‘Iwakeli‘i, are horizon opposites; when one is rising the other is setting.
Thus, people in Kona did not need to see Makali‘i rising to know that the Makahiki season was beginning; all they had to do was look to the west — where they had a clear view of the ocean — and watch Nahiku set into the sea.
Evening observations
The planets Jupiter and Saturn continue to accompany each other in November’s early evening sky.
Jupiter will appear brighter and closer to the southwest horizon; as the largest planet in the solar system, Jupiter is one of the brightest objects in the sky.
Next to Jupiter in the southwest will be the fainter planet of Saturn; through a good telescope observers will be able to view its famous rings. These planets have been caught up in a cosmic dance throughout 2020, and on the winter solstice (Dec. 21), the planets will appear to be right on top of each other in a conjunction.
In the northeastern part of the sky, you will be able to see the faint Andromeda galaxy. To find it, first find the bright W shape of ‘Iwakeli‘i and look about 15 degrees south of its lowest, brightest star.
To the naked eye, the galaxy appears to be a small, faint, blurry smudge in the night sky. This galaxy is about 2.5 million light-years away from us, meaning the light that enters our eyes when we see it has traveled 2.5 million years before hitting Earth. Andromeda is the closest galaxy to our Milky Way.
Through mid- to late November, the spectacular Leonids meteor shower will scatter our sky with shooting stars. These meteors come from the tale of the comet Tempel-Tuttle, a periodic comet which last swept through Earth’s orbit in 1998. The peak of the shower will occur Nov. 17, when you should see at least 10-15 meteors each hour.
On the evening of Nov. 29, the full moon might appear a bit darker in color as it enters the outer portions of Earth’s shadow in a penumbral eclipse. Compared with the “blood moon” of full lunar eclipses, penumbral eclipses are much less dramatic, with the moon simply taking on a dark gray color. The penumbral lunar eclipse will begin at 9:32 p.m. in Hawaii with maximum eclipse occurring at 11:42 p.m.
Morning observations
Throughout November the sun will rise between 6:34 and 6:52 a.m. with dusk coloring the sky starting between 5:45 and 6 a.m.
During the early morning hours observers can see a very different area of the sky. Two particularly bright objects will stand out along the eastern horizon.
The brightest object at this time will be Venus, rising just south of east within the 4 a.m. hour. Venus is the third-brightest object that we ever see in the sky, after the sun and the full moon. The planet’s distinctive brightness has made it famous throughout history, and it has been referred to as the Morning (or Evening) Star.
Just north of east in the early morning hours will be a bright and notable star, Hokule‘a, also known by the Western name Arcturus. Hokule‘a is the zenith star for Hawaii, meaning that it is in a perfect position where it will rise to the exact center of the sky. Hokule‘a’s unique position makes it a notable star for wayfinding.
November 2020 Sky Chart by Honolulu Star-Advertiser
Chad Kalepa Baybayan (Kalepa.Baybayan@hawaii.edu) serves as navigator-in-residence and Emily Peavy (Emily.Peavy@hawaii.edu) as planetarium technician support facilitator at the ‘Imiloa Astronomy Center of Hawaii, a center for informal science education at the University of Hawaii at Hilo showcasing astronomy and Hawaiian culture as parallel journeys of human exploration.
