In what astronomy groups believe is the first such discovery by an amateur in 65 years, McNeil photographed the illuminated cloud of gas and dust lit by what astronomers believe is a newborn star.
Such a discovery is exceedingly rare, said Bo Reipurth, who confirmed the find at the Institute for Astronomy at the University of Hawaii, home to one of the world's largest telescopes.
"This is exciting for all astronomers, especially those interested in the birth of stars," Reipurth said. "We tend to think of the sky as fixed and unchanging, so when we see something new it's important."
According to McNeil and the space education group, Students for the Exploration and Development of Space, fewer than a dozen other similar discoveries have been made, with the last one made by an amateur in 1939.
McNeil's nebula is about 1,500 light years from Earth, meaning that what he witnessed was a star being born centuries ago.
This particular nebula did not show up in sky survey photographs from 1951-91. It was reported in 1966, but was never recorded, according to the Students for the Exploration and Development of Space, based at the Massachusetts Institute of Technology.
McNeil, a satellite dish installer from Paducah who's been an amateur astronomer for 20 years, first saw the nebula on Jan. 23 while looking at star formation regions in the Orion constellation. He snapped pictures of Orion through the three-inch (7.6-centimeter) lens of his telescope, but the images sat idle for days before being processed.
Once he had them developed, though, McNeil noticed a star he hadn't seen in previous sky surveys — what turned out to be the nebula.
"It was just too conspicuous an object for me not to have seen before," he said.
After realizing he had something unique on his hands, McNeil contacted a friend, Brian Skiff, with the Lowell Observatory in Flagstaff, Arizona. Skiff also saw something new and referred McNeil to Reipurth.
Within 48 hours, Reipurth focused the large telescope at the university on McNeil's find and confirmed it.
Getting Reipurth to act so quickly was an indication of just how unusual spotting the nebula was, McNeil said, since scientists reserve time on the telescope as much as a year in advance.
"The wheels of science do not move that quickly," McNeil said. "That told me this was quite a discovery."
The discovery has thrilled amateur astronomers in bluegrass country, said Warren Wepking, president of the Western Kentucky Amateur Astronomers.
"We're all just so excited," Wepking said. "This is something that doesn't happen very often."
For the 32-year-old McNeil, the discovery is the payoff of a passion he's had since he was a teenager and saving money to buy telescopes.
"It didn't do much to attract the girls," he said. "But this is something permanent. It's just what I do."