Posted on: Sunday, October 3, 2004

Hawai'i sunsets will frame 2 partial eclipses

By Mike Shanahan
Bishop Museum

After five years of producing this monthly column, I am bowing out of writing the Skywatch article. Carolyn Kaichi, who assumed the role of planetarium manager when I became the museum's education director last year, will produce this article in future (we're writing the current October article together).

Carolyn is a graduate of the University of Hawai'i and worked for many years in the television field before returning in 2001 to the Bishop Museum (where she had previously been a part-time planetarium presenter) as a planetarium show producer.

Sunset Eclipse, Part I

The only solar eclipse visible from the Hawaiian Islands in 2004 occurs shortly before sunset on Oct. 13. At 5:15 p.m. on that Wednesday, the moon will begin to move in front of the sun. If you have a view of the western sky and a safe viewing device, it will look like the moon is taking a little bite out of the sun. By the time the sun sets (at 6:09 p.m. in Honolulu, 5:51 p.m. in Hilo, and slightly different times elsewhere), the moon will cover about one-quarter of the sun.

This eclipse will occur when the sun is very low on the western horizon, so there is a good chance that those pesky horizon clouds will interfere with our view of this partial eclipse. For the best bet of catching it, find a place that has a view to the west with no hills or buildings in the way. The Wai'anae coast of O'ahu, for instance, should be a good area. An ocean view from a tall building is good, too.

It is never safe to view a partial solar eclipse directly. Even a small sliver of direct sunlight is enough to do permanent eye damage.

Sunset Eclipse, Part II

Two weeks later, on Oct. 27, we'll have another eclipse around sunset. As the moon rises at 5:54 p.m. on that Wednesday it will just be coming out of total lunar eclipse, seen over most of the Americas and parts of Europe. This is the last total eclipse of the moon until 2007. If you are fortunate to have a view of the rising moon in the east (not necessarily the case on the Leeward side) you may notice that the moon seems a little darker than usual for a full moon. However, because there will still be a glow in the sky from the setting sun, the darkened moon effect will probably not be very dramatic on Oct. 27. By the time the moon rises over the Koolaus around 7 p.m. the eclipse will be pretty much over, as will any noticeable darkening of the full moon.

Coincidentally, this full moon also happens to be the Hunter's Moon — following the Harvest Moon and so called because now that the fields are reaped, hunters can easily see their prey and stock up for Thanksgiving dinner.

Fall constellations

Early October is the time of the Dipperless night — the only time of year when it's almost impossible to see the Big Dipper in the evening or the morning sky. By the time it gets dark, the Dipper has set; and dawn lightens the sky just before the last stars of the Dipper rise above the horizon in the morning.

By Nov. 1, the Big Dipper is entirely up by 4 a.m., a couple of hours before dawn.

The beloved little cluster called the Pleiades rises in the eastern sky around 9 p.m. in early October and around 7 p.m. at the end of the month. The rising of the star cluster at sunset 2000 years ago was used to mark the new year for the Celtic people, many of whose traditions survive to this day in Halloween.

Following the Pleiades, the constellation of Orion springs over the eastern horizon by midnight in early October and by 10 p.m. on Halloween night.

More October Skies

The Orionid meteor shower, debris from Halley's Comet, peaks on the night of Oct. 20-21. Observers may see as many as a dozen shooting stars per hour as the constellation of Orion starts to rise due east at about 10 p.m. The first-quarter moon sets a little after midnight, so viewing should be good from then until dawn. The shower lasts over the entire second half of October, at lesser intensity.

Oct. 31 is the end of Daylight Saving Time for most of the U.S. mainland (Hawai'i does not observe DST; nor do Arizona and most of Indiana). As of Oct. 31, the West Coast will be only two hours ahead of us, and the East Coast will be five hours ahead.

Venus in the morning

Venus is brilliant in the morning sky all of October. By daybreak Venus is about one-third of the way up in the eastern sky. It is the brightest natural object in the sky except for the sun and moon. Look for a very slender crescent moon next to Venus on the morning of Oct. 10.

Saturn is the first planet to rise in the early morning hours, at about 1 a.m. at the start of the month and a little after 11 p.m. by the end.

Jupiter is not visible in the first week or so of October. Look for it in the morning sky starting around Oct. 10, when it will rise at 5:30 a.m. Jupiter will be dimmer than usual but still brighter than any star.

During the final week of October, Jupiter and Venus draw closer and closer to one another. By Nov. 4, the King of the Gods and the Goddess of Beauty will be less than 1 degree apart.

Too close to the sun to be visible in October, Mercury appears as the sole evening planet by the end of the month, appearing low in the west after sunset.

Mars is behind the sun and not visible until November.