Sunset, February 13, 2000

Source: Sam Low

The dense clouds that have been following us now receeded far astern behind the gently swaying running lights of Kama Hele. Overhead, the sky dome is clear where the half moon now presents itself above our masts at sunset. The wind is cool. The crew don t-shirts and jackets as they go on watch. Tava, leaning against the aft safety rail says, "... going to be a nice night."

At 6 p.m., our navigators conclude we are at 6 22' S latitude and 58 miles west of our course line. Having sailed 54 miles since sunrise, we are now about 1880 miles from Hawai'i. Among the celestial clues we use to steer our course are: Mars, setting in Komohana (west); Jupiter and Saturn setting in La Ho'olua (1 house north of west); and Venus rising in 'Aina Malanai (2 houses south of east).

Tonight the navigators will pay particular attention to observing two pairs of stars: Murzim (a star near Sirius or A'a) and Alhena (in Gemini); and Saiph and Betelgeuse in Orion. During his painstaking observations of the stars in the Bishop Museum Planetarium, Nainoa discovered a variety of star pairs that appear to set simultaneously when the observer is at a very specific latitude. He calls this phenomenon "synchronous setting." Mirzim and Alhena, our first pair - and Saiph and Betelgeuse, the other pair both set simultaneously at only 6 S.

"We will be looking carefully at both star pairs tonight," Shantell says, "because we think we are about 6 S and so if they do set simultaneously, it will help confirm our dead reckoning position." In fact, the navigators have been mentally plotting their position through dead reckoning ever since departing Tikehau without a solid celestial observation as a reality check.

"Ideally, you only navigate by dead reckoning for about 360 miles when making a passage from Tahiti to Hawai'i," says Nainoa, "but because we have had so much bad weather we've been dead reckoning for about 750 miles and that's not comfortable. So I'm looking forward to getting some good celestial clues by looking at the star pairs and also observing Kochab or Holopuni."

During the morning navigator's meeting shortly after sunrise on Valentine's Day, the navigators report our position as 5 27' S, 68 miles west of our reference course line.

"We observed the two star pairs setting at the same time last night," Shantell says, "so we are pretty confident of our latitude. We are also pleased that our latitude estimates by dead reckoning are very close to what the stars indicate which give us additional confidence about our position."

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