When you're talking a big planet, how do you decide the Earth's birthday? Is it when the first life emerged from the primordial ooze? Is it when all of a sudden the Earth could support life? Was it when the first intelligent beings looked around them and said, "Hey, cool place. Let's call it born?"

Well, here we are on that big blue marble we call home. Lots of famous people get holidays, so why not the home to us all? The official Earth Day is Sunday, but Homer celebrates on Saturday from noon-3 p.m. at the Alaska Islands and Ocean Visitor Center.

Don't get cocky, though, and think that Mother Earth cares about her children, like she's going to go all Mama Bear and get mad if something threatens her cubs. When her cubs threaten her, Ma Earth rolls with the punches. You think a planet that has endured killer asteroids and continent-wide volcanic eruptions is scared by a bunch of naked apes who do bad things with opposable thumbs?

As if. Earth survived the Ice Age and the last arrogant species to think it had things made, those dinosaurs. You know what happened to the dinos, doncha? They got evolved into birds. Parrots. Hummingbirds. Bald eagles. Let that be a warning.

So be nice to your mother and she'll be nice back. Pick up some trash, recycle, turn down the thermostat, you know the drill. And hey, after you've done a good turn for our common home, why not celebrate with some of these Best Bets?

BEST MEGABOOKS BET: It's National Library week, with lots of cool events continuing through the weekend, like Support Teen Literature Day from 10 a.m.-8 p.m. today, when The Friends of the Homer Library launches Youth Focus 2007. Litmania continues on Friday for Young People's Poetry Day.

BEST JUST SAY NO WAY BET: The troopers and cops have been pretty firm about this: If you don't want drugs in your town, the community has to stand up and say, "Not here." Learn more about how to fight back at 7 p.m. today in the Chapman School gym, when people who know a little more than us talk about the impact of meth and other drugs on the lower Kenai Peninsula.

BEST YOU ROCK, ROCKERS BET: Reading books and playing rock 'n' roll music? There's hope for the next g-g-generation. This week, Homer's finest rock bands play for yet another good cause: building schools in Jamaica. Mostly Red, CTTC, Token Counter Slug and Mr. Roily and His Kooky Clams play from 8:30 p.m.-midnight today at the Homer Theatre. Admission if $8 or $5 if you bring a bag of school supplies. Proceeds benefit the Blue Mountain Project.

BEST ART ALL THE TIME BET: There's so much art in this town we need a second Friday to showcase all the cool talent. From 5-7 p.m. at Ptarmigan Arts, check out the Kachemak Bay Campus Student Art Showcase opening, when art students show off what they've done in the college's spanky new studio. Stroll down the hill and support more art when Bunnell Street Gallery unveils this year's painted plates, a premium for joining or renewing your membership.

BEST WATCH THE DUST BET: Curious about the South Peninsula Hospital expansion? Want to see the new emergency room without getting injured? Borrow a hard hat and check out the building from 5:30-7:30 p.m. Friday for this month's Homer Chamber of Commerce Mixer. Use the front entrance and check in at the cafeteria.

BEST ALL ABOUT THE DUDES BET: What does it mean to be a man in the days of sensitive new age guys? How do boys come of age? Dr. Deland Anderson leads a discussion from 6:30-8 p.m. at Fritz Creek General Store, this month's Pratt Museum Community Conversation. Food is available for purchase.

BEST BRAIN TO BRAIN BET: The Kenai Peninsula's best and brightest go head-to-head at 7 p.m. Saturday in a smackdown of smarts. Homer and Nikiski High School debate teams vie for the coveted Golden Halibut in the Land's End Quarter Deck. The topic? "Should the U.S. Military be prohibited from recruiting in American high schools?" Hey, people have been known to get arrested about issues like that.

Homer's Best Bets