The author of "Mark My Words: Mark Twain on Writing" (1996) and "Horton Foote's The Shape of the River: the Lost Teleplay About Mark Twain" (2003), Mark Dawidziak has presented academic papers at the last three State of Mark Twain conferences. He has twice been the guest speaker for the Elmira College Center for Mark Twain Studies' lecture series. And he often portrays Twain in appearances with the touring troupe he co-founded, the Largely Literary Theater Company.

Halley's Comet revisits our planet about every 75 years. When Samuel Langhorne Clemens was born on Nov. 30, 1835, it was blazing across the night sky over his family's cabin in the tiny Missouri town of Florida.

The world knew Sam Clemens by his pen name, Mark Twain. And if you know much about Mark Twain, you probably know that, when he died on April 21, 1910, Halley's Comet was visible in the night sky over his last home, Stormfield, near Redding, Conn.

Even more amazingly, this was a called shot.

"I came in with Halley's Comet in 1835," Twain told a friend in 1909. "It is coming again next year, and I expect to go out with it. It will be the greatest disappointment of my life if I don't go out with Halley's Comet. The Almighty has said, no doubt: 'Now here are these two unaccountable freaks; they came in together, they must go out together.' Oh, I am looking forward to that."

So, 100 years ago this Wednesday, 74-year-old Mark Twain packed up his white suit and cigars, climbed on the back of Halley's Comet and pulled off the greatest stage exit in literary history.

"This is merely the centennial of his physical death," said Robert H. Hirst, general editor of the vast Mark Twain Papers collection at the University of California at Berkeley. "Mark Twain was very forthright in saying he was no great believer in life after death. But there's no question he has achieved immortality through what he wrote. Mark Twain is more alive today and in more ways than any other writer."

About 13 years before Twain's actual departure from this globe, a rumor went around that he was near death. So a reporter dispatched to cover Twain's impending death was as surprised to find him alive and well as the author was to hear that he was supposed to be dying. Twain famously suggested that the reports of his death had been greatly exaggerated.

"Turns out, he was right," said comedy legend Carl Reiner, who received the Kennedy Center's Mark Twain Prize in 2001. "The truth is, he never went away. People have never stopped turning to him as a source of wisdom and common sense. And every once in a while, somebody rightly notices that 'Huckleberry Finn' is the closest thing we have to the great American novel."

Symbolically, therefore, as soon as we pass Wednesday's 100th anniversary of Twain's death, we move ever closer to the 175th anniversary of his birth. And 2010 also marks the 125th anniversary of the American publication of "Huckleberry Finn."

A former Mississippi riverboat pilot and a failed miner, Sam Clemens adopted the pen name Mark Twain as a frontier reporter in February 1863. His early fame was built on his formidable talents as a humorist, but, while wit and satire remained writing weapons of choice throughout Twain's life, his work took on increasingly dark and complex hues.

"He remains the most-quoted American writer because he said so many quotable, pithy things," said Shelley Fisher Fishkin, the Twain scholar who has authored such landmark books as "Was Huck Black?: Mark Twain and African-American Voices" and "Lighting Out for the Territory: Reflections on Mark Twain and American Culture."

"But he also gets away with telling us unpleasant truths about ourselves. We'll take it from Mark Twain because, although brutally honest, he isn't malevolent. You get the idea that, no matter how foolish we are, he won't abandon us."

Fishkin has gathered other writers' opinions of Twain in the recently published "The Mark Twain Anthology."

"Twain understood the humor of creatures who paid lip service to ideals that they constantly violated," she said. "Dick Gregory has one of the most cogent observations in the 'Anthology,' saying that Twain 'was so far ahead of his time that he shouldn't even be talked about on the same day as other people.' Another is from Richard Wright: 'Twain hid his conflict in satire and wept in private over the brutalities and the injustices of his civilization.'"

Twain's first best seller was the travel book "The Innocents Abroad" (1869). It was followed by "Roughing It" (1872), "The Adventures of Tom Sawyer" (1876), "The Prince and the Pauper" (1881), "Life on the Mississippi" (1883), "Huckleberry Finn," "A Connecticut Yankee in King Arthur's Court" (1889) and "Pudd'nhead Wilson" (1894). Many of his darker writings were published long after his death in such volumes as "Mark Twain in Eruption" and "Letters From the Earth."

"One of the things I'm most proud of is my recording of 'Letters From the Earth,' " said Reiner, who also recorded a CD version of "A Connecticut Yankee." "And 'A Connecticut Yankee' is what started me reading. I read it while I was on 'Your Show of Shows' in the early 1950s. I was never a big reader before that. I read the baseball scores. But it was one of the great experiences of my life."

Reiner continually extolled Twain's virtues in a writers' room that included Neil Simon, Mel Brooks and Larry Gelbart.

"I made everybody read it," he said. "The Mark Twain Prize was the greatest award I ever received. It's the only award I keep in my den."

To Ohio native William Dean Howells, Twain was nothing less than "the Lincoln of our literature." To William Faulkner, he was "the first truly great American writer." To Eugene O'Neill, he was "the true father of American literature." And Ernest Hemingway, of course, declared that "all modern American literature comes from one book by Mark Twain called 'Huckleberry Finn.' "

"What Ernest Hemingway recognized was that 'Huckleberry Finn' wasn't just the wellspring of all modern American literature, it was America's literary Declaration of Independence," Fishkin said. "It was a book no Englishman could have written, and it expanded the possibilities of what a novel could do."

"Huckleberry Finn" also continues to kick up controversy, with its use of the n-word and its treatment of black characters sparking demands for it to be removed from libraries and required reading lists.

" 'Huckleberry Finn' makes us uncomfortable because it should make us uncomfortable," Fishkin said. "Twain is challenging us in honest and compelling ways to grapple with these painful chapters of our past, and that's still controversial. And well it should be, because debating this book is a very useful exercise for our nation. That's another reason Twain's work is so alive to us today.

"It's quirky, ambitious and strikingly original, but it also engages many of the thorny issues we're still grappling with today, not the least of which is the great contradiction of a nation founded on freedom by men who owned slaves. I think Toni Morrison gets to the heart of this in her magnificent introduction to the Oxford Mark Twain edition of 'Huckleberry Finn.' "

Morrison wrote: "What it cannot be is dismissed. It is classic literature, which is to say it heaves, manifests and lasts."

Filmmaker Ken Burns, who made a documentary about Twain, couldn't agree more: "Russell Banks said in our film that Twain identified the two great issues of the American story: race and space. And he's still making us confront those issues."

Twain also asked Americans to confront the pursuit of the almighty dollar, runaway greed, political corruption, prejudice and hypocrisy.

"For a man dead 100 years, he certainly has a lot to say to us," said Cleveland native Hal Holbrook, who has been touring his acclaimed one-man show, "Mark Twain Tonight!", since 1954. "The man's ability to nail the body of deception and half-lies and corrupt intelligence to the wall is extraordinary. I love Twain's attacks on petrified thoughts and secondhand opinions. I like to make people think -- to use Mark Twain to get people out of their partisan ruts and see something bigger."

The reports of Mark Twain's death also have been greatly exaggerated because the scholarship built up around him is so alive.

"It's very much the study of a living presence," Berkeley's Hirst said. "We are finding new Mark Twain letters at a rate of two a week. And that should continue. He wrote at least 50,000 letters, and we have only 10,000 of them."

Twain once observed that humor must teach and preach if it will live forever. This is yet another reason he's still alive.

"He remains funny 100 years after his death," Hirst said. "Why is a blue-jay human? Twain tells us that the blue-jay is human because he lies, he cheats, he steals, he swears, he can't keep his word. Well, nobody is attacking humans there, right? He's just explaining what blue-jays are. He's making fun of things that are eternal. He attacks things that are still of concern to us, and he does it so well, we still smile."

Twain said that the problem with the world isn't that there are too many fools, it's that lightning isn't distributed properly.

"That was funny in the 19th century, it's funny in the 21st century, and it will be funny, if we don't blow ourselves up, 1,000 years from now," Burns said. "Our greatest American author? I don't even know a close second. Anyone vying for second, whether you're talking Melville or Fitzgerald, he lapped them several times over."