The four stars that form the corners of Ka Lupe A Kawelo, the Great Square of Pegasus, are excellent pointer stars that point in the direction of both the north and south celestial poles, and serve as an indicator of the path it takes across the night sky as it moves from the eastern to the western horizon.

The first two stars that appear in the east are Kakuhihewa (Scheat), rising on the boundary of the compass house Noio-‘Aina Ko‘olau, and Keawe (Markab), rising on the boundary of ‘Aina-La Ko‘olau. Because they rise at about the same time, they will cross the celestial meridian together making them a Meridian Pointer.

Meridian Pointers are any two stars that cross the celestial meridian together and, in the tropics, they are excellent pointer stars to the celestial north and south poles.

The second pair of stars in Ka Lupe A Kawelo to arrive in the east are Manokalanipo (Alpheratz) and Pi‘ilani (Algenib). They rise and set along the same boundaries of Noio-‘Aina Ko‘olau and ‘Aina-La Ko‘olau. These two sets of pointer stars point toward the north celestial pole.

To find the south celestial pole, draw a line through Kakuhihewa (Scheat) and Keawe (Markab); continue the line southward and through Kukaniloko (Fomalhaut) for one set of southern meridian pointers.

For the second set of pointers, draw a line through Manokalanipo (Alpheratz) and Pi‘ilani (Algenib) and through Kaikilani (Ankaa) for the second set of pointers. By using the four stars of Ka Lupe A Kawelo in this way you can identify both the north and south celestial poles.

Because Kakuhihewa and Manokalanipo, and Keawe and Pi‘ilani rise and set in the same compass house they will always point out the direction to those compass houses on the horizon. Within the tropics, you can draw a line between these stars and calculate the angular path these stars take on their nightly east to west trek.

MAUNAKEA DISCOVERY

Jupiter’s moon, Europa, has intrigued astronomers for decades.

Since the moon was first closely observed with the Voyager and Galileo spacecraft, strong evidence of a subsurface ocean on the moon was detected.

The presence of this ocean led many astro-biologists to consider Europa to be the most likely place to research for life elsewhere in our solar system as it may possess all of the ingredients necessary for life.

Scientists have evidence that one of these ingredients, liquid water, is present under the icy surface and may sometimes erupt into space in huge geysers. But no one has been able to confirm the presence of water in these plumes by directly measuring the water molecule itself.

An international research team led by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, has detected the water vapor for the first time above Europa’s surface by peering at Europa through W. M. Keck Observatory on Maunakea. For more of this groundbreaking discovery, visit http://www.keckobservatory.org/europa-vapor/

DECEMBER SPECIAL EVENTS

The Geminid meteor shower, considered by many to be the best meteor shower of the year, runs through the first couple weeks of December and peaks at 8:25 a.m. on Dec 14. While the peak is during the day for Hawaii, a multitude of shooting stars in the days around the peak will still be visible.

The Geminid meteor shower is somewhat peculiar because the meteors for this show do not originate from a comet but from the asteroid 3200 Phaethon, whose orbit passes close to Earth’s orbit every 1.433 years.

In 2017, this asteroid had a relatively near Earth approach (about 10 million kilometers, or 27 lunar distances from the Earth) which allowed astronomers to study the asteroid in great detail.

Winter Solstice for the northern hemisphere takes place on Dec. 21, where the sun will rise and set at its southernmost position in the sky.

The sun will travel at its lowest arc across the sky, marking the shortest day and longest night of the year. On Dec. 21 in Honolulu, the sun will rise at 7:04 am and will set at 5:54 pm, yielding only 10 hours and 50 minutes of daylight. The days will be getting shorter and the nights will be getting longer up until Dec 21, after which the days will slowly start to get longer again.

DECEMBER OBSERVATIONS

As the days get progressively shorter in the winter season, observers will be able to start stargazing as early as 6:30 p.m. Immediately after sunset, Venus, Jupiter and Saturn will be visible.

Both Jupiter and Saturn will be setting fairly quickly.

Throughout December, Venus will appear to be climbing up in the western sky, setting at 7:45 p.m. Dec. 1 and at 8:35 p.m. Dec. 31.

Among the brightest objects in the sky, Venus is often seen immediately after sunset and has been referred to as “the evening star.” On Dec. 10, Venus and Saturn will go through a conjunction, when the two planets appear extremely close (about 2 degrees) to each other in the sky, and this pair of planets will be setting at 8 p.m.

While looking toward the body of Ka Lupe A Kawelo, about 10 degrees north and west of the star Manokalanipo, and almost 20 degrees south of ‘Iwakeli‘i, you can see a small faint smudge in the sky. This faint object is the Andromeda Galaxy, the closest full-sized galaxy to the Milky Way and the only object visible to the naked eye that is outside of Earth’s own galaxy.

The Andromeda Galaxy is about 2.5 million light years away from Earth; meaning that it is over 2.5 million years old. It is worthy to note that a number of globular clusters, the Large and Small Magellanic clouds and dwarf galaxies, which are outside of the plane of the Milky Way, are visible; however, these objects are gravitationally bound to the Milky Way within the halo of our galaxy.

Rising from the east is the distinctive star cluster of Makali‘i, also known as the Pleiades. This stellar open cluster stands out with its seven brightest stars being clearly visible to the naked eye. The stars in the cluster were all born from the same nebula about 100 million years ago. As these stars are around the same age, the cluster can be used as a laboratory for the study of stellar evolution.

MORNING OBSERVATIONS

Throughout December, the sun will be rising between 6:52 am and 7:08 am. The early-morning sky will look different from the evening sky. For the first half of the month, the faint planet Mercury will be rising immediately before the sun rises and will be obscured as it appears to move closer to the sun. However, Mars will also stand out in the eastern sky during these early-morning hours. In the early morning, Hanaiakamalama, the Southern Cross, will return to our Hawaii skies. This notable shape of stars will begin to rise in the southeast about an hour before the sun rises.

KEKEMAPA (DECEMBER) SKIES A… 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.