Kenwood observatory hosting solar eclipse party Saturday

Sonoma County residents will be among millions of people in the Western Hemisphere able to view some part of an annular solar eclipse Saturday morning.

While the “ring of fire” effect — when the moon crosses in front of the sun but does not fully cover it — that occurs during annular eclipses won’t be fully visible in Sonoma County, locals will see a partial eclipse, said Jack Welch, a docent at the Robert Ferguson Observatory in Kenwood’s Sugarloaf Ridge State Park.

“The exact amount and time depends upon one’s location. For those in or near Sonoma County, the eclipse begins around 8 a.m. or so and ends around 10:40 a.m. or so,” Welch said in an email Tuesday evening. “Around 78% of the solar disk will be covered at maximum, which occurs around 9:19 a.m.”

Telescopes equipped with solar filters will be set up for the public to safely view the eclipse at the observatory, and solar eclipse glasses will be available for $2.

The free, informal event will run from 9-10 a.m. Saturday. A $10 vehicle entry fee or annual parking pass will be required upon entering the park.

“The first thing we stress about solar eclipses is safety,” Welch said. “It is very important not to look at the sun directly without appropriate equipment. Doing so can cause eye injury up to blindness.”

It is also dangerous to aim optical equipment of any kind at the sun unless it is specifically designed for solar viewing, he said. Sunglasses or other dark filters not specifically designed for solar viewing are not safe to use.

If you want to see the full “ring of fire” during the eclipse, you’ll have to travel to a narrow area spanning parts of Oregon, Nevada, Utah, the “Four Corners” area, New Mexico and Texas, according to Welch.

“For this eclipse, the moon’s disk will be smaller than the sun’s disk so it will not cover the entire solar disk during the eclipse even for those directly in line with the sun and moon,” Welch said. “Those people will see a bright ring (’annulus’ in Latin) of the solar disk surrounding the moon’s disk.“

For more information on the viewing party, visit rfo.org.