Surely you noticed this urgent news item over the weekend: The red swimsuit worn by Farrah Fawcett in her iconic 1976 poster has been donated to the Smithsonian’s popular culture history collection. Along for the ride were some of Fawcett’s “Charlie’s Angels” scripts, a Fawcett doll, a hairstyling kit called Farrah’s Glamour Center and, of course, the poster itself.

Do such artifacts belong at the Smithsonian? That’s the question, all right; but seeing the famous photograph has a way of making you forget, for a moment, to ask it. It’s pure, perfect 1976. The heedless tan, the cascade of hair (lightened with real lemons, we’re told), the thin gold chain and, of course, the shocking outline of a nipple through the damp one-piece suit ― it all looks as dated as the avocado-colored kitchen appliances in vogue at the time, even a little cheesy. But it somehow remains as titillating as ever, a kind of cultural template for the post-Nixon-era definition of “hot.”

Which is why it’s interesting to contemplate another image associated with the story, an Associated Press photograph of the suit on a mannequin, as it officially entered the Smithsonian collection. The Norma Kamali maillot now appears more burnt orange than red, and it looks shockingly plain, like something you’d see on a competitive swimmer instead of on a pinup model in the bestselling poster of all time (in fact, the brand of the suit has sometimes been misreported as Speedo).

And while Fawcett could probably have worn a grocery bag and still dominated the wall art of teenage boys’ rooms everywhere, it’s hard to imagine that a bestselling swimsuit poster these days would be such a no-frills affair.

Not that there’s anything new about that. Sexiness just keeps getting sexier, or at least more revealing. Clara Bow, the first It Girl, in the 1920s, looks like a veritable librarian compared with her 1930s successor Mae West, who in turn seems positively matronly compared to the 1940s’ Betty Grable, who might as well be invisible next to come-hither Marilyn Monroe and Brigitte Bardot.

Having arrived at a moment when the line between pinup girl and porn star has been blurred into near invisibility (the celebrity sex tape, once a potential career buster, has become a valuable piece of media real estate), it’s tempting to look at Fawcett’s one-piece bathing suit, lanky golden limbs and unaugmented breasts as emblems of a simpler time ― or at least a time before the culture became obsessed with weight training, plastic surgery and sunscreen.

But here’s the problem with trying to compare that swimsuit poster to its modern equivalent: You can’t. There is no equivalent, and not because no woman in the last three decades has ever hit quite so perfect a pose as Fawcett with that one shutter click during that one photo shoot. (Madonna was in line for the title in the 1980s, but she was too much of a shape shifter to truly assume it.) It’s because the concept of iconic sex symbol just isn’t compatible with the Information Age.

There is no longer one ubiquitous It Girl; there are many It Girls. They’re found not only on bedroom walls but also on countless cable channels and deep inside the hard drives of anyone who can type “hot chick” into a search engine. They’re not just models and actresses but socialites and reality stars and people who don’t do anything much.

I could name names ― Megan Fox, Jessica Alba, Kim Kardashian, Paris Hilton ― but even though they all popped up when I Googled “biggest sex symbol 2011,” I suspect many readers of this column won’t even have heard of some of them.

And that’s why Fawcett’s swimsuit may well deserve a place in the Smithsonian (bearing in mind that its collection already includes a Phyllis Diller wig, Fonzie’s leather jacket from “Happy Days” and the infamous “puffy shirt” from “Seinfeld”). Fawcett may not have been the biggest sex-symbol pinup of all time, but she was the last of her kind ― the last one we could all agree on, or at least the last one we all shared.

And sharing, in a sense, is what we’ll now be doing with her suit. Let’s just hope it stays on that mannequin.

By Meghan Daum

Meghan Daum is an essayist and novelist in Los Angeles. ― Ed.

(Los Angeles Times/McClatchy-Tribune Information Services)