The Navigators and the Night Sky
- Posted on 13 Jun 2014
- In Crew Blogs
We’ve studied for countless hours, looking at star maps, computer simulations of the night sky, and the heavens themselves back home in Hawai‘i, but nothing can compare to the real deal on the open ocean.
The night sky and the angles that the stars rise at have changed noticeably, giving us an almost uncomfortable feeling as we venture into the unfamiliar. We’ve studied for countless hours, looking at star maps, computer simulations of the night sky, and the heavens themselves back home in Hawai‘i, but nothing can compare to the real deal on the open ocean—no light pollution, no distractions, just you, your navigation partner and the 100 or so stars we use to organize the chaos that the night sky appears to be to the untrained eye.
We’ve lost Hokupa‘a, the North Star, a reliable and comfortable friend that was such a gift to set our course by in the northern hemisphere; now must now patiently wait for various star pairs that point to north as they cross the meridian.
An example is the pair of northern pointers, Ed Asich and Pherkad (Ka‘aumoana). Ka‘aumoana’s declination is 72º (measured from the celestial equator), and thus it is 18º away from Hokupa‘a, the North Star. When Ed Asich and Pherkad are at the meridian (an imaginary line dividing the sky into rising and setting halves), you can determine where due north is by drawing an imaginary line through the two stars down to the horizon.
By measuring with your hand the height of Ka‘aumoana above the horizon, you can determine latitude south of the equator. This is done by subtracting the number of degrees Ka‘aumoana is above the horizon from 18º (the distance of Ka’aumoana from the North Star).
When day turns to night we hold our course by the rising and/or setting moon and the planets, Jupiter and Saturn, because they shine the brightest.
As the night progresses we also use the brightest stars in the sky such as ʻĀʻā (Sirius major) as itʻs setting in the west; Keoe (Vega) as it’s rising in the east; and Hanaiakamalama, the Southern Cross, off of our bow. Using these and a few other bright heavenly bodies, we are able to determine the direction in which we are heading.
The most rewarding thing about being one of the seven student navigators on this voyage has been working with Haunani Kane, my navigation partner. We communicate well and lookout for one another on the wa‘a. We try to make sure that each of us gets enough rest while on watch, gets whatever the other needs if one of us is sick, and try to relieve stress for the other as best we can, even if we might be the one causing it.
I think working in pairs is great on this first deep sea voyage, because it takes away some of the pressure; you have someone immediate to turn to for help, whose experience is the same as yours; and it’s more fun working with a partner, you’re not alone. The most challenging experience of the voyage started last night and continues on as I’m writing this. The winds are coming from a more southerly direction and have increased in strength. A large southeast wave has formed making for a very uncomfortable and battering ride which is kind of hard on the canoe and crew as well. We’re fighting for every inch of easting we can get as we head south and it is incredibly challenging to keep Hōkūleʻa from running down wind and to the west.
It seems like any easting we do get can be lost in a second by a slight change in the heading of the wind or a collision with a big wave, so it’s very frustrating. But it’s good to be with your friends slugging it out in the trenches as we make our way back down the road of our ancestors. And if it weren’t tough, would it really be worth doing?