October is eclipse month

The new issues of Astronomy and Sky & Telescope magazines arrived in the mail over the last couple of days with reminders that a couple of cool events should be visible from Seattle in October. There will be a total eclipse of the Moon in the early morning hours on October 8, and a partial eclipse of the Sun in the afternoon on October 23.

The lunar eclipse October 8 will begin in Seattle at 1:15 a.m. Pacific Daylight Time with the onset of the faint penumbral eclipse. The real show starts about an hour later when the Moon enters Earth’s umbral shadow. The eclipse will reach totality at 3:25 a.m. and the Moon will remain in complete shadow for just under an hour. The umbral eclipse will be over at about 5:35 a.m.

As an added attraction during the eclipse, the planet Uranus will be close by the shadowy Moon, passing about one degree south of it during the event. You will need binoculars or a telescope to spot Uranus, which is at the best point for observing it this year. It will reach opposition to the Sun October 7, and thus is up all evening and is at its closest to Earth.

Animation showing the moon’s penumbral shadow sweeping from west to east across the Earth’s surface on October 23, 2014.

Animation showing the moon’s penumbral shadow sweeping from west to east across the Earth’s surface on October 23, 2014.

The partial solar eclipse October 23 happens at a much better hour for those of us in the northwest. In Seattle the eclipse begins at 1:35 p.m., will reach its maximum at 3 p.m., and be over at 4:20 p.m. All times are Pacific Daylight Time.

It is not all that unusual to see a partial solar eclipse, but this should be a particularly good one, as about 64 percent of the Sun’s disk will be covered by the Moon from our vantage point.

We’re lucky to be in Seattle, as the eclipse will cover more of the Sun the further north you go. The maximum for this eclipse is some 81 percent up in northern Canada. On the other hand, we’re unlucky to be in Seattle, as we average only five clear days during October, when the Sun’s rays reach us during only about 37 percent of daylight hours. So we’re rolling the dice a bit when it comes to actually having breaks in the clouds so that we can see the eclipse. Ever the optimists, we note that October is not our worst weather month, and we have the dates for both eclipses marked on our calendar.

Please remember never to look at the Sun without proper eye protection. The eclipse glasses at right are a good a low-cost choice. They and a number of other options are available from the software and accessories section of our Seattle Astronomy Store. If you’re using a telescope or binoculars, make sure they’re fitted with solar filters; looking at the Sun through an unfiltered magnifier can cause serious eye damage in a big hurry. If you don’t have the right equipment, it’s a good bet to try to find out if an astronomy club near you plans a viewing event. As of this writing, we know that the Tacoma Astronomical Society plans a free public solar eclipse watch at Pierce College and the Pierce College Science Dome. We know of no others at the moment, but imagine that plans will be made in the coming weeks.

Seattle Astronomy will probably be out somewhere about town with our telescope and some solar shades if the weather looks favorable on eclipse day. We’ll keep you posted about our plans.