Despite the gloomy weather, Bay Area skywatchers will be eagerly awaiting tonight’s total lunar eclipse, which falls on the northern winter solstice—the moment at which the Earth’s axis is tilted farthest from the sun, giving us our shortest day and longest night of the year, and heralding the first day of winter. According to NASA Science News, there’s only been one other lunar eclipse on the northern winter solstice in the last 2,000 years … and that one was back in 1638.

According to information from Oakland’s Chabot Space & Science Center, the eclipse will begin when the Earth’s shadow begins to slide across the full moon at 9:30 pm Monday night. Complete coverage—known to astronomers as “totality”—will last from 11:40 pm until 12:53 am on Tuesday, and the eclipse should be over by 2:00 am. (An animation of how it works can be seen here at ShadowandSubstance.com.)

The eclipse should be visible to viewers throughout North America and western South America, but the view may be obscured in the Bay Area by the heavy cloud cover accompanying recent storms. NASA Science News projects that the very best moment for West Coast observers to catch a peek will be at 12:17 am Tuesday—that’s the moment when, from our vantage point, the moon will be fully in shadow. If you can see the moon through the clouds, expect it to appear red or amber as the Earth’s shadow falls across it.

Lunar eclipse on March 20, 2008, photographed by Chabot astronomer Conrad Jung. Photo courtesy Chabot Space & Science Center.

In Oakland, Chabot is offering “Midnight Delight,” a special program based on mythology and lore surrounding the moon, which event organizers promise will take place from 9:00 pm Monday until 2:00 am Tuesday come “rain or moonshine.” If the weather is good, Chabot will offer visitors a chance to view the eclipse via its telescopes, and astronomers will be on hand to talk about the science of eclipses. Weather permitting, eclipse buffs watching from home can also tune in online via Chabot’s NellieCam, a camera affixed to Nellie, the observatory’s 36-inch reflecting telescope. If the skies remain overcast, Chabot will present a simulated eclipse in its planetarium.

For those of you watching from home, it is safe to look at a lunar eclipse with the naked eye. And if you miss it, well, hang tight. There will be another winter solstice lunar eclipse in 2094.

Information about tickets for Chabot’s “Midnight Delight” program can be found here. You can check for the lastest local weather updates via our new Oakland North Yahoo! weather page. NASA’s eclipse page, with dates for upcoming solar and lunar eclipses, can be found here.

Top lunar eclipse photo © 2010 Fred Espenak, www.MrEclipse.com