What do you do on Earth Hour?

Turn out the lights.

Or at least, that’s what will happen at the Capitol Building in Olympia and City Hall in Spokane from 8:30 p.m. to 9:30 p.m. on Saturday. It’s part of a worldwide observance of Earth Hour.

Not to be confused with Earth Day, which is in April. (And considering that the Earth is, like, the only planet we have, shouldn’t it at least get a month? But don’t let’s go down that road…)

The Capitol dome lights will go off for that hour, and Washington residents are being encouraged to turn their lights off then, too, in a show of support. (At the rate the Legislature is going, one might argue the lights could stay out in that part of the Capitol for days, and no one would notice.)

Gov. Chris Gregoire will sign a proclamation supporting Earth Hour, although it’s not quite clear if she’ll sign it by candle light, kerosene lantern, or just have someone flick their lighter until it’s signed. Or everyone could just open their cell phone, and the screen glow will light the room.

Spokane City Hall, the Clocktower in Riverfront Park and the Pavilion will also be lights out at that time at the direction of Mayor Mary Verner.

So if you’re out and about on Saturday evening, and the light on a public building suddenly go off, it’s not a sign that someone forgot to pay their Avista bill.