Welcome to Slate's 80 Over 80, our annual catalog of the nation's silver lions: fourscore elder statesmen, titans of industry, cultural icons, and notorious newsmakers who have remained influential into their ninth decade and beyond. As always, we've ranked these still-twinkling stars according to their power and importance, with extra credit given for energetic achievements post-80 and for being really, really old.

For the second year in a row, Mormon President Thomas S. Monson stands atop the list. As the divine prophet, seer, and revelator for 5.5 million Americans and more than 12 million people around the world, he's the most powerful 83-year-old we could find. Look for Monson to stay on top for years to come—at least until Boyd K. Packer, octogenarian president of the Quorum of the Twelve Apostles, succeeds him as the alpha Mormon.

First runner-up is the senior senator from Hawaii, Daniel Inouye. When West Virginia's Robert Byrd moved into our "Just Missed" section in June, the 86-year-old Inouye was sworn in as president pro tempore of the Senate—which puts him just three heartbeats away from the Oval Office. He's also the chairman of the appropriations committee—and responsible for about $400 million in earmark spending in 2010.

Last year's No. 2, John Paul Stevens, plummeted to the bottom of the list after resigning from the Supreme Court over the summer. He's not ready to drop off, though—the man still plays a regular game of singles tennis and has been writing influential essays for the New York Review of Books. Other geezers in sharp decline include Liz Smith, the 87-year-old * gossip columnist who was finally canned last year from her longtime gig at the New York Post. Then there's Helen Thomas—she launched a sprightly attack on the legitimacy of Israel in her 90^th year and was forced to retire her column for Hearst Newspapers.

Meanwhile, the Republican takeover of the House pushed some geriatric congressmen ahead in the rankings. Ralph Hall, the 87-year-old representative from Texas, will soon become the chairman of the committee on science and technology; he's up 16 spots from last year. Roscoe Bartlett, a 10-term GOP member from Maryland (and holder of multiple patents for life-support equipment), jumped four places.

A batch of fresh old faces dots the top rows on the list. Billionaires Warren Buffett and George Soros just turned 80, as did Hollywood's most eminent gris, Clint Eastwood. The naturalist and formic novelist E.O. Wilson shows up at No. 8, and Paul Volcker, chairman of the president's Economic Recovery Board, slides in behind Si Newhouse at No. 12. And of course we couldn't fail to include the 92-year-old exercise freak and audio-equipment tycoon Sidney Harman, who purchased Newsweek from Slate's parent company in August for a shiny dollar.

As usual, we've got an impressive list of 79ers to watch for next year, including Nobelist Toni Morrison, media mogul Rupert Murdoch, and deep-sea shipwreck-hunter Clive Cussler. They're not Mormon prophets, but they have potential to join the elect. Stay tuned.

Correction, Nov. 30, 2010: This article originally stated that Liz Smith was fired at age 87. She was 86 when she lost her column at the New York Post. (Return to the corrected sentence.)

Correction, Dec. 3, 2010: In the chart accompanying the article, Vin Scully was listed as 82 years old. He turned 83 the day before the feature was published. Joe Paterno was listed as 84 years old. He won't be 84 until Dec. 21.

Correction, Dec. 9, 2010: In the chart accompanying the article, it was stated that John Kluge's $400 million gift to Columbia was specially intended for minority students; in fact, it was for general need-based student aid.

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