Florida Fish and Wildife via Flickr

The eyeball that caused a sensation was cut from a swordfish's head, apparently by a fisherman, scientists say.

The giant eyeball from Florida that captured the world's attention came from a swordfish, scientists reported today. They said straight-line slashes on the softball-sized orb suggest that it was freshly cut out of the fish's head by a fisherman and tossed overboard. The fact that it washed ashore and was found by a beachcomber so quickly contributed to a rare string of circumstances that sparked last week's collective "ewws" and "ahhs."

"It's definitely been unusual to have a situation quite like this," Kevin Baxter, a spokesman for the Florida Fish and Wildlife Conservation Commission, told me today. The commission has been fielding tons of inquiries ever since pictures of the eerie eyeball turned up on Thursday. If you haven't seen them yet, be sure to check out the commission's Facebook page and Flickr gallery.

Observers had speculated that the eye might have come from a large fish, or a giant squid, or even a whale — but in retrospect, the scenario involving a swordfish caught at sea seems to make the most sense. Genetic testing is being conducted to confirm the hypothesis.

Here's the explanation from the commission's news release:

"After examining an eye found on a south Florida beach this week, researchers from the Florida Fish and Wildlife Conservation Commission believe the specimen came from a swordfish. Genetic testing will be done to confirm the identification.

"'Experts on site and remotely have viewed and analyzed the eye, and based on its color, size and structure, along with the presence of bone around it, we believe the eye came from a swordfish,' said Joan Herrera, curator of collections at the FWC’s Fish and Wildlife Research Institute in St. Petersburg. 'Based on straight-line cuts visible around the eye, we believe it was removed by a fisherman and discarded.'

"The approximately softball-size eye was recovered by a citizen in Pompano Beach on Wednesday. FWC staff received the eye later that day. Swordfish are commonly fished in the Florida Straits offshore of south Florida at this time of year.

"A highly migratory fish, swordfish can be found from the surface to as deep as 2,000 feet. Swordfish in the Atlantic can reach a maximum size of over 1,100 pounds, according to the National Oceanic and Atmospheric Administration. Swordfish feed on a wide variety of fish and invertebrates."

More sea marvels:

• Florida fishermen pick up dying giant squid
• Hawaiian squid carries a built-in light
• Boy finds a bonanza in whale vomit
• Gallery: 10 deep-sea secrets revealed

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Carli Segelson / Fla. FWCC via AP

A photo from the Florida Fish and Wildlife Conservation Commission shows a giant eyeball from a mysterious sea creature that washed ashore and was found by a man walking the beach in Pompano Beach, Fla., on Wednesday. The eyeball will be sent to the Florida Fish and Wildlife Research Institute in St. Petersburg, Fla.

A giant eyeball that washed ashore and was found by a beachcomber in Pompano Beach, Fla., is mystifying wildlife officials — but probably not for long.

The softball-sized eyeball was reported to the Florida Fish and Wildlife Conservation Commission on Wednesday, and wildlife officers put the specimen on ice. It will be preserved and sent to the Fish and Wildlife Research Institute in St. Petersburg, Fla., for analysis.

Marine biologists couldn't immediately identify which species of sea creature would be associated with the eye, but researchers will use genetic testing if necessary to solve the mystery, said Carli Segelson, a spokeswoman for the commission. "I shouldn't say this, but they may be able to eyeball it," she told me today.

Segelson said she's been fielding tons of inquiries about the case, especially since a picture of "THE MYSTERY EYEBALL" was posted to the commission's Facebook page. "It's just gone viral," she said. There are more pictures in the commission's Flickr photo gallery.

Some have suggested that the eye came from a monster fish, a giant squid or even a whale. It does look a bit like this picture of an eye from a giant squid, but Segelson said wildlife officers are leaning toward a different scenario.

"The primary suspect right now is that it would be a large fish," she said. Among the possibilities are a swordfish, or a tuna, or some sort of deep-water fish species.

What do you think it is? Feel free to give it your best shot a comment below, and keep your eyes peeled for the answer.

More sea marvels:

• Florida fishermen pick up dying giant squid
• Hawaiian squid carries a built-in light
• Boy finds a bonanza in whale vomit
• Gallery: 10 deep-sea secrets revealed

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

NASA

The lights of the Florida Peninsula and the rest of the southeastern U.S. glow in this picture taken from the International Space Station on Nov. 24.

Florida's city lights shine brightly in this night view from the International Space Station — but there's a completely different kind of glow that frames the edge of our planet. It's known as "airglow," the faint greenish radiance high up in Earth's atmosphere.

You might think airglow comes from the reflected glare of city lights, but it's actually a photochemical reaction caused by the sun's ultraviolet radiation.

During the day, that radiation breaks apart molecules of oxygen and other chemicals, exciting them into a higher energy state. During the night, the molecules recombine, radiating the excess energy as light. As a result, the atmosphere glows in a thin region around 60 miles up.

The glow is so faint that it can't be seen when you're looking up into the sky, or when astronauts are looking directly down from space. But when space travelers look toward the edge of Earth's disk at night, they can see the permanent aurora at the horizon. For more about airglow, check out this explanation from the University at Albany's Bob Keesee, or this one from Discovery News' Jason Major.

We've seen some great views of airglow from the space station over the past year: For more examples, check out these archived PhotoBlog items, and keep an eye on NASA's Gateway to Astronaut Photography of Earth as well as astronaut Ron Garan's postings on Google+ for "Fragile Oasis."

The hits just keep on coming from the space station, and you can expect to see much more when the station's crew is back at its full strength of six astronauts.

Three new crew members are due to arrive this week, just in time for Christmas. In this video, space station commander Dan Burbank reflects on the new arrivals, the holidays and our "indescribably beautiful" planet:

The space station crew's sidelong glance at the Florida Keys, the Florida Peninsula and the rest of the southeastern United States was captured from orbit on Nov. 24. It's today's offering from the Cosmic Log Space Advent Calendar, which highlights views of Earth from space every day from now until Christmas. Catch up on these previous gems from the calendar:

• The full Cosmic Log Space Advent Calendar
• Dec. 1: An ornament in outer space
• Dec. 2: The masses in Mecca
• Dec. 3: Santa's shrinking domain
• Dec. 4: The monster of Madagascar
• Dec. 5: Antarctica stripped naked
• Dec. 6: Streaking for home
• Dec. 7: Pearl Harbor from above, 1941-2011
• Dec. 8: The rise and fall of the Dead Sea
• Dec. 9: How an eclipse dims Earth
• Dec. 10: Psychedelic storm
• Dec. 11: Beauty of the Inland Sea
• Dec. 12: Drone-spotting stirs up debate
• Dec. 13: Light up your St. Lucy's Day
• Dec. 14: Satellite spots Chinese aircraft carrier
• Dec. 15: Hooray for Hollywood
• Dec. 16: Olympics under construction
• Dec. 17: Mystery in the Gobi Desert
• Hubble calendar, from The Atlantic's In Focus
• 2011 Zooniverse Advent calendar