In last month’s “Sky Watch,” we discussed the star family Manaiakalani, The Chiefly Fishing Line, and what can be found in the northeastern quadrant of that line of stars. The Summer Triangle, which is comprised of Keoe, Vega in the constellation Lyra the Harp; Pira‘etea, Deneb in the constellation Cygnus the Swan; and Humu, Altair in the constellation Aquila the Eagle, occupies the northeastern quadrant of that star family.

This trio of stars represents a spool of fishing line coiled at the bottom of a canoe that leads to the southeast quadrant and is attached to the top of Kamakaunuiamaui, Maui’s Fishhook, also known as the constellation Scorpius.

It is not hard to imagine why Polynesians thought that this constellation resembled a fish hook or why Babylonians and Greeks thought that it resembled a scorpion. At the center of Kamakaunuiamaui is Lehuakona, Antares, the heart of the fishhook, a red supergiant irregular variable star.

It is the 15th brightest star in the night sky and, if placed within our solar system, it would stretch between the orbits of Mars and Jupiter. In wayfinding, the three stars right after the curve of the fish hook, where the bait would be attached are meridian pointers, meaning that they pass through the celestial meridian fairly close to each other. Meridian pointers are used to identify the celestial poles; in this case these three stars would point toward the direction of the south celestial pole.

Navigators see the fishhook as fishing for an ulua, a celestial crevalle, made up of Sagittarius, magical Pimoe, from the tales of the demigod, Maui. Pimoe is a recognizable asterism, seen as a celestial teapot, with a cover, spout and handle. Within Sagittarius lies our Milky Way galaxy. In a section of Sagittarius defined as Sagittarius A (SgrA), astronomers have evidence that there exists a supermassive black hole.

The Keck Telescope and The Very Large Telescope have detected stars orbiting SgrA at velocities greater than other stars. Star S0-2 was clocked at over 5,000 kilometers per second at its closest approach to SgrA. Astronomers utilize the Keck Observatories to study this star at its closest approach to the supermassive black hole. In doing so, astronomers are able to test Einstein’s Theory of General Relativity. Read more about this research here: keckobservatory.org/ghez-einstein/

Mauna Kea discovery

Meanwhile, astronomers use the Gemini Observatory to further understand a supernova event, which is rewriting the way we understand the explosive deaths of stars. The supernova SN 2016iet marks the death of a star 200 times the mass of the sun, making it one of the most massive and powerful star explosions ever observed. As we gain further understanding about the early days of the universe, our evidence suggests that the first stars in the universe would be of a similar mass and would have died in these unique forms of supernova. This new breed of supernova utterly annihilated its parent star, leaving no remnant.

As astronomers continue to study SN 2016iet more mysteries arise. While most stars form and live in dense clusters, this supernova is alone and separated from the center of its dwarf galaxy by 54,000-light years. The question of how such a massive star could form in isolation is leading astronomers to even more questions about the lives and deaths of the first massive stars in the universe — those which led to our own origins.

Read more about this groundbreaking research here: gemini.edu/node/21217

September events

September’s full moon will occur on Sept. 13, when the moon is at a point in its orbit called apogee. At this point, the moon is at its furthest distance from the Earth in its orbit and it will often appear to be a little bit smaller in our sky. When the moon is full while it is at apogee, it is often referred to as a micromoon.

Sept. 22 marks the autumnal or fall equinox when the sun will be rising exactly east and setting exactly west.

In the Northern Hemisphere, it is celebrated as the first day of fall. Despite the name “equinox,” this day will not actually have equal parts day time and night time. In Hawaii, Sept. 28, will be the day with the closest amount of equal day and night, with the day lasting 12 hours and 38 seconds. As we approach winter season, the sun will be rising and setting in the southern sky and our days will be getting shorter.

Evening observations

Jupiter and Saturn will both be visible in the early-evening sky. Jupiter will stand out in the early evening as one of the brightest objects in the sky, while Saturn will be much fainter and to the east of Jupiter. These two planets are the largest planets in our solar system.

Through a good telescope we will be able to see Jupiter’s four largest moons: Ganymede, Callisto, Io and Europa. These large moons are often referred to as the Galilean moons as they were first discovered by Galileo Galilei in 1610, using a telescope as powerful as a pair of modern-day binoculars. These moons are some of the largest moons in the solar system and continue to intrigue astronomers here in Hawaii.

Researchers using the Gemini Observatory and Keck Observatories have studied unique eruption patterns on Io, the most volcanic object in the solar system, and have observed the thin atmosphere of this moon collapse as the moon enters the shadow of Jupiter. Astronomers in Hawaii have helped confirm the presence of salt on Europa’s surface, indicating that the ocean beneath Europa’s ice could be similar to Earth’s oceans.

As the summer star family of Manaiakalani prepares to leave our evening sky, the fall star family of Kalupea­kawelo, the kite of Kawelo, will be rising in the east during the early evening. Within this star family will be the recognizable shape of ‘Iwakeli‘i, also known as Cassiopeia, in the north.

Morning observations

Throughout September, dawn will begin to color the sky at around 5:30 a.m., and the sun will be rising around 6:15 a.m. 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 in the sky as the sun rises.

KEPAKEMAPA (SEPTEMBER) SKIE… by Honolulu Star-Advertiser on Scribd

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.