The death of N.Y. Giants great Bobby Thomson on Tuesday at the age of 86, drove me back to my on-again, off-again sub-hobby of investigating what exactly happened to the “Bobby Thomson ball” — the one that Thomson launched on October 3, 1951 and that ended up in the left field stands at the Polo Grounds. Thomson’s “Shot Heard Round The World” gave the Giants the 1951 pennant (“the Giants win the pennant, the Giants win the pennant”), and ranks as the most memorable home run in baseball history. The Thomson home run lives on in film and book and legend. An important part of that legend is consumed with determining what exactly happened to the ball after it landed in the left field seats — where is it, who has it, and what is it worth? Those questions have engaged a generation of memorabilia hunters, amateur sleuths and famous authors –a gaggle of hobbyists whose obsession surely equals that held by a generation of cranks who wonder (still) whether there were shots from the grassy knoll.

How much of a mystery is this? A few years ago, a baseball auction house in New York offered $1 million to anyone who could produce “the Thomson ball,” which spurred a new round of “let no rock remain unturned” charnel house of baseball gurus and ghost hunters to begin the search anew. To no avail: the reward remains unclaimed, the ball unfound. The question of what happened to the “Thomson ball” is so consuming that even noted American authors and filmmakers have weighed in: Don DeLillo fictionalized the travels of the ball as a key dynamic in his novel Underworld (if you haven’t read it, you should), while Francis Ford Coppola, in the Godfather, has parkway attendants listening to the Thomson game when Sonny is murdered at a toll booth — a bit of apocrypha for sure, as we all know (don’t we?) that Sonny was murdered in 1948, not in 1951. Tsk, tsk, tsk. Then too, the flight of the ball sparked Giants followers and baseball afficianados to identify and question nearly every fan who was out in left field that day, going over and over the film of Thomson’s dinger as if it were the Zapruder film. Without appreciable result.

Still, I became convinced several years ago that author and baseball obsessive Brian Biegel has probably provided the best answer to the mystery. Biegel, whose father Jack claimed he bought the ball for $2 at a Long Island Salvation Army store, set out to prove him right — and (alas) ended up proving him wrong. After years of investigation, Biegel showed that a baseball loving nun (“Sister Helen”), who attended the Giants-Dodgers game in violation of her Franciscan convent rules, snagged the ball and carried it with her in a shoebox her entire life. When she died many years later in Albuquerque (and after a lifetime of selfless devotion to her order), her colleagues in the convent lovingly sorted through her personal belongings, found the ball and gave it to her sister. And what did the sister of Sister Helen do with the ball? She looked over the ball, shrugged her shoulders, shook her head and deposited both shoebox and ball in a landfill.

Bobby Thomson hit “the shot heard round the world.” Thomson’s walk off home run came at precisely 3:58 pm, New York time, on October 3, 1951 — and is considered the most dramatic moment in baseball history. Thomson’s bottom of the 9th shot came off  Brooklyn Dodgers’ right hander Ralph Branca with two men on. With the Dodgers leading 4-2, Branca threw Thomson a first pitch fastball over the center of the plate. The next pitch was inside and high and Thomson swung. The hit was not a towering fly ball, but a line drive that sailed into the left field seats of the lower deck in the Polo Grounds. It gave the New York Giants a 5-4 win and the N.L. Pennant, two games to one. The two teams had finished the season with identical 96-58 records. The Giants had taken the first of the three game playoff series (3-1) and the Dodgers the second (10-0). Deadlocked at one game apiece, the third game would decide the pennant. What made Thomson’s home run even more dramatic is that the Giants had won 37 of their last 44 games to force the playoff, having trailed the Dodgers by 13 games in mid-August.

Also known as “The Miracle of Coogan’s Bluff,” Thomson’s home run is celebrated in the immortal broadcast of Russ Hodges that was heard on WMCA-AM radio — “The Voice of the New York Giants”: “There’s a long drive… it’s gonna be, I believe…The Giants Win The Pennant! The Giants Win The Pennant! The Giants Win The Pennant! The Giants Win The Pennant! Bobby Thomson hits into the lower deck of the left-field stands! The Giants win the pennant and they’re goin’ crazy, they’re goin’ crazy!”

For many years it was not known what happened to Thomson’s home run ball. While innumerable myths have surrounded its whereabouts (most recently in Don DeLillo’s Underworld), it is now believed that a Franciscan nun recovered the ball and kept it in a shoebox for fifty years. When she died, her sister collected the shoebox and deposited it in a landfill. Willie Mays, then 20, was on deck when Thomson hit his home run.