In a stunning discovery, scientists at the Massachusetts Institute of Research have announced that the 5K marathon, long thought to be a legend, may in fact be an actual race distance.

"We're very excited," said Daniel Partridge, Ph.D., who led the effort. "Until now we'd assumed the 5K marathon was a mythical construct, a fable. Something that people liked to talk about but that, of course, didn't exist—sort of the Loch Ness Monster of the road racing universe."

Like everyone else, they also assumed logically that a 5K marathon was a mathematical impossibility. After all, a 5K by definition is 3.1 miles; a marathon, 26.2. The very term 5K marathon, then, would seem paradoxical.

But through sophisticated computer modeling and quantum mechanics, and with "an awful lot of trial and error," Dr. Partridge and his assistants made their breakthrough last week.

"We were surprised, to say the least," Partridge said. "We checked our work two, three, four times. But there it was—the very real possibility that 5K marathons do indeed exist."

"And not just on Earth, either," he added.

Partridge said his colleagues congratulated him on his discovery by spraying him with bottles of Lemon Lime Gatorade.

Other groups, too, were celebrating.

"Finally, vindication," said Ann B. Davis, a spokesperson for the National Association of Newspaper Reporters, a trade group. "We've been mentioning 5K marathons in our articles for years, and it's earned us nothing but ridicule. It is gratifying to learn that maybe we knew what we were talking about all along."

Dr. Partridge, widely known as a restless intellect and tireless worker, already has his sights on the horizon.

"The next logical step," he said, "is to prove the existence of the 10K marathon."

But first, perhaps, will he celebrate? By running a 5K marathon, maybe?

Dr. Partridge laughed.

"No, no, no," he said. "I don't run. Bad for the knees."