One of the least heralded -- and most significant -- events of Pittsburgh's 250th anniversary celebration is the 2008-09 Carnegie International, "Life on Mars," and its unique accompanying book.

The exhibition itself indelibly imprints visitors' imaginations; the book is one of few enduring birthday year achievements. Both are reflective of the mood of this particular time period and of the city's often overlooked historic participation in global culture.

It's true that the International would have returned to Carnegie Museum of Art whether or not the region was marking an important milestone. But the effort expended for the 55th installment, its year 2008 scheduling, and the expansion of its run time were planned to complement the larger occasion.

Because of the exhibition's mandate -- to present "a discriminating overview of contemporary art" -- Internationals generally include works (and artists) that will exist in the spotlight only momentarily, while others will enter the art historical canon. With insight and luck, Carnegie curators select from the latter category to add to the museum collection, in accordance with founder Andrew Carnegie's wishes.

But until the doors close Jan. 11, the entirety -- an enticing mixture of profundity and extravaganza -- is there to enjoy (see below for some exhibition notes).

International '08-09 curator Douglas Fogle has actually created two exhibitions. One is ephemeral and will linger only as memory in the Carnegie galleries, with the exception of Richard Wright's impeccable "No Title" that will maintain imperceptible physical presence behind a coating of white paint once the show closes. The other is permanent, existing within the 440-page book, which is certainly product of the exhibition but also expansive of and tangential to it (hardcover, $39.95).

It is also simultaneously personal and global, as are the Internationals, drawn from a vast pool, meant to be representational of what's being created now, chosen with input from a variety of sources, but ultimately the vision of one man or woman made physical.

What visitors see in the museum halls is necessarily a synthesis, of the larger creative world and of the work of each artist. Through this thoughtfully conceived and engaging book (it is more than a catalog) Fogle provides a means to experience the complexity of interests that drove his curatorial choices as well as to more fully appreciate individual artists.

Short commentary on and bios for each artist are included, as well as color photographs of their artworks, including those in the exhibition when possible (some installations were still being constructed by print deadline).

The real distinction is Fogle's choice of essays, opening with his own intellectual and poetic query, "Is There Life on Mars?" In it, he refers to Jonathan Swift's satirical "A Modest Proposal" of 1729, which he publishes in full in the following pages.

For the first time, artists' writings are included in an International book, and 13 of the 40 exhibiting artists contribute, their entrees ranging from playful to sobering. Essays by Fogle's four advisory panel members include an interview with activist artist Paul Chan, who exhibited in CI04-05.

The publication's size, 6 3/4 by 9 1/4 inches, makes it comfortable to hold, and the silky cover is tactile and inviting. Fountain-pen blue text printed on heavy stock is barely restrained by narrow margins, suggesting the boundlessness of (Martian) space, as does the deep blue cover with its silver-white type, the word "on" clipped as though emerging from another dimension.

Altogether, it's a handsome addition to the literature of contemporary thought and art.

Here are some suggestions for enjoying the exhibition, but you're certain to discover much more along the way. Free gallery guides will help with works at which you choose to linger:

Don't miss: Cao Fei's film "Whose Utopia," Richard Wright's "No Title," Ranjani Shettar's "Just a Bit More."

Surprises: Thomas Hirschhorn's "Cavemanman," Mike Kelley's "Kandors," Barry McGee's untitled installation.

After dark: Look for Doug Aitken's "Migration: 365 Hotel" projected outside, on the front and back of the museum. Also note how wonderful Rudolf Stingel's paintings, which hang near the museum cafe, appear from Forbes Avenue.

Award winners: Painter Vija Celmins was awarded the Carnegie Prize and filmmaker Apichatpong Weerasethakul received the first ever Fine Prize for an emerging artist.

Seminal figures: Mario Merz (1925-2003) and Paul Thek (1933-1988). Also Bruce Conner, who died July 7 (after the exhibition opened) and is represented by ethereal photograms that radiate light and spirit.

Sound pieces: By Susan Philipsz in the Sculpture Courtyard and the Music Hall.

Is it real?: Look again, as at Peter Fischli and David Weiss' "Untitled."

Child friendly: Rivane Neuenschwander's "I Wish Your Wish."

Child warning: Depending upon maturity, one room of Thomas Hirschhorn's "Cavemanman;" adolescent scenes in Sharon Lockhart's "Pine Flat."

For film buffs: Sharon Lockhart's "Pine Flat," 138 minutes long, lyrical, but with beautifully framed images and a cumulative impact both heartbreaking and idyllic. (Note that it screens daily at 2 p.m., and the room is somewhat chilly.)

Museum hours are 10 a.m. to 5 p.m. Tuesday through Saturday, noon to 5 p.m. Sunday, and until 8 p.m. Thursday (closed Thanksgiving). Admission is $15, seniors $12, students and children 3 and older $11, under age 3 and members free. For information, call 412-622-3131 or visit www.cmoa.org.