Photo: Winter/Getty

“Hello, Planet Earth!”

Brandon Flowers of the Killers wasn’t addressing the entire globe as he paused onstage Saturday at the Coachella Music and Arts festival, but as he watched over a desert landscape of thousands of bouncing, singing, happy fans, it must have felt like the band’s own celestial body. As the mainstage’s headlining act on Day Two of the epic SoCal fest, the Killers steered the party for two danceable hours.

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The Killers represented just one of many disparate musical flavors in a full day of rock, folk, hip-hop and DJ sounds, with stirring sets by M.I.A. and TV On the Radio. For the Killers, the festival was an opportunity to deliver their euphoric pop on a massive scale, opening with “Human” (from last year’s Day & Age), before moving on to such breakthrough hits as the pleading “Somebody Told Me” and a storm of fireworks and flashing lights.

Just as celebratory, but a thousand times more confrontational, the hour-long set by M.I.A. began with news footage of protests against the singer for her outspoken lyrics on Sri Lankan politics. The rapper initially appeared behind a politician’s podium in the farcical uniform of a military dictator, and was joined by five dancers in colorful neon outfits.

In 2005, her memorable first Coachella appearance was on a much smaller tent stage and she also performed to a jam-packed tent last year, so M.I.A. approached this weekend’s gig on the large-scale Coachella Stage as a challenge. “I don’t know how we’re going to bring it to the mainstage,” she said, “but we’ll try.”

There were chaotic beats, samples and sirens on “Pull Up the People,” and she invited a crowd of dancing fans to join her onstage. She performed the crossover hit “Paper Planes” (built on a sample of ’70s rock revolutionaries the Clash), while keeping the song’s Grammy nomination and Oscar connections at arm’s length: “It doesn’t mean I’ve sold out. We’re taking it back to the jungle!” She also added her own take on a familiar Amy Winehouse jingle (she was actually Winehouse’s Coachella replacement after the British singer pulled out due to visa issues): “They tried to make me do the Oscars, I said no, no, no!”

TV On the Radio delivered an afternoon onslaught of raw, soulful sounds and bristling energy with “Staring at the Sun.” Singer Tunde Adebimpe performed “Dancing Choose” in a mad rush, while the pained “Young Liars” bounced hard from a brass section anchored by Geoff “Double G” Gallegos on baritone sax. Thievery Corporation’s set included a roaring, sophisticated storm of post-modern and timeless world beats around the core DJ duo of Rob Garza and Eric Hilton. There was emotional longing within “Sweet Tides,” but also songs of thieving bankers, crazy baldheads and injustice on both a global scale on the brassy “El Pueblo Unido” (from last year’s Radio Retaliation album). Early in the set, Perry Farrell arrived to perform “Revolution Solution,” his 2005 collaboration with Thievery Corporation, wailing across a stuttering guitar riff before exiting with a pirouette.

If M.I.A. and Thievery Corporation sounded ready for a “revolution solution,” and Henry Rollins told jaw-dropping spoken-word tales of “homeland security,” a number of scraggly young American acts looked ready for the country, headed by the spectral folk of Fleet Foxes, Band of Horses and Blitzen Trapper.

The delicate, forceful music of Fleet Foxes included the angelic harmonies of “White Winter Hymnal,” though competing beats and volume from Thievery across the field crashed over the Seattle band, even as singer Robin Pecknold wailed and slashed at his acoustic guitar on “Tiger Mountain Peasant Song.” Earlier, the six-piece Blitzen Trapper rode wild flights of guitar melody and feedback, with extended tunes of fuzz and contemplation, and Band of Horses fired up three electric guitars for another round of forceful Americana.

Bearded rock of an entirely different tradition and intensity shook the Mojave tent at the end of the night, as Mastodon performed their new Crack the Skye album in its entirety. The Atlanta quartet may or may not have been the loudest act of the festival, but they were easily the heaviest, sending out the concusive riffs and beats of “Oblivion” and “Divinations” into the warm desert air, bringing Day Two of Coachella 2009 to a thundering close.

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