X-ray of baseballs reveals possible cause of home run surge

Big League Stew via Yahoo ^ | March 3rd, 2018 | Liz Roscher

[Mariner]

The home run surge of 2017 (and before) has been a heck of a lot of fun, but there are many outstanding questions about what’s really behind it. And now we might have the most compelling answer yet. Rob Arthur and Tim Dix of FiveThirtyEight published the findings of CT scans and other experiments that had been done on new and game used baseballs from before and after the official start of the surge (the 2015 All-Star Game), and what they’re reporting is undeniable: the core of the baseball has changed.

Arthur and Dix reported the findings of experiments commissioned by ESPN Sports Science. A CT scan was done on eight different baseballs: one purchased new from Rawlings, four game-used balls from April 2014 through May 2015 (before the surge began), and three game-used balls from August 2016 through July 2017 (after the surge started). The CT scan revealed that the core of the newer baseballs are approximately 40% less dense than the older balls. Further testing of the chemical composition of the less dense baseballs revealed that Rawlings used a more porous substance to seal the core, which led to the decrease in density.

A less dense core means a lighter baseball, and the newer baseballs are an average of 0.5 grams lighter than the old ones. Arthur and Dix admit that a lighter baseball on its own wouldn’t cause a huge jump in homers. But when added to existing research on the new baseballs done by Arthur at FiveThirtyEight and Ben Lindbergh of The Ringer, it turns into something significant.

[KSCITYBOY]

Saw an article in KC star years ago said GW was the cause totally ignored performance enhancing drugs

[KSCITYBOY]

Added strength gets more over the fence.

[al baby]

Me and mrs al baby go to lots of angel games i kiss her on the strikes and she kisss me on the balls

[MikeD]

Read the Book THE YEAR BABE RUTH HIT 104 HOME RUNS

I second this recommendation. Excellent book, well written and researched, with plenty of diagrams, pictures, charts, and explanatory text. The Babe would beat Barry Bonds's record by the All-Star break with today's parks, let alone modern training, scheduling, and travel comforts.