ROCKPORT — A vessel bobbing along the currents in Rockport Harbor has raised quizzical eyebrows since it first appeared last week. Lobstermen make a few investigatory circles around it before shrugging shoulders and heading out to check traps. Locals walking dogs or eating lunch peer over the wharf’s edge at the blue shape, theorizing it’s part of a broken weather station or a downed Russian satellite.

But it is art. And geometry.

Sean Patrick O’Brien lives on Bear Island in Penobscot Bay, where he is caretaker of the family corporation that owns the island. Bear Island is Buckminster Fuller’s former summer home, and when you say Buckminster Fuller, images of geodesic domes and the dymaxion car logically follow.

Fuller is known for his rejection of conventional academics, and for being an inventor, architect, philosopher and teacher. He designed the geodesic dome, “the only kind of building that can be set on the ground as a complete structure and with no limiting dimension,” according to the Buckminster Fuller Institute. “The strength of the frame actually increases in ratio to its size, enclosing the largest volume of space with the least area of surface.”

The geodesic dome influenced architecture and technology through the 20th-Century, and right now that spirit is evident in Rockport Harbor.

The vessel is half a geodesic dome, and it is a boat. Sort of. It floats and a person can climb in there and not capsize. But paddling won’t get one too far, too fast.

“It’s a plankton float,” said O’Brien. “It's more about floating and not having control.”

O’Brien is an artist whose work is part of the Biennial Exhibit, a collection of artwork at the Center for Maine Contemporary Arts, which is (still, until 2016) in Rockport Village. Since 1970, CMCA has held a juried show every two years for artists with strong connections with Maine. The work on display consists of pieces that were created within the past two years.

More than 475 artists applied for the 2014 CMCA Biennial exhibition, according to the gallery, and O’Brien is one of the 28 artists exhibiting there until Dec. 7. 

His half geodesic dome will be in the harbor until then, as well. Another piece of his art is outside the gallery.

The work “is my attempt to make geodesic domes,” he said, speaking over the phone from Bear Island, under halting cellular reception. Bear Island is on the other side of Islesboro, nestled close to Butter and Eagle islands.

“In this case, I was inspired by Buckminster Fuller and the boat he built on Bear Island,” said O’Brien. “I made one that was sort of in the shape and would float. I think it's such a simple shape that has inherent DNA.”

The half-dome — “maybe it’s a little more than half” — in the harbor consists of 20 of the same-sided triangles that are made from plywood and stitched together with copper wire and glued fiberglass.

“They are varied and simple and repetitive,” he said.

He has also outfitted its cockpit with a solar lamp.

“It is a cross between a buoy and a lighthouse,” said O’Brien.

The blues it is painted with are inspired by the “razzle-dazzle” painting on Navy ships, to “give some sort of signals that its has some sort of purpose.”

It was CMCA that suggested the dome go into the water, in the harbor.

O’Brien is now considering other uses for it. Maybe he will install a camera there, looking up at the sky and around the landscape, so that people around the world can see what it is like bobbing around Rockport Harbor. Or, document its journey as it floats freely around.

“We’ll see if that’s practical or not,” he said. 

To O’Brien the artist, who admits he is drawn more to science than art, the intention was to “make the most simple core vessel to keep me afloat.”

“The structure is so simple,” he said.

Its construction is a repetitive act: “that allows me not to think too much about why. It is a way of going directly from the idea, skipping the blueprint, and going straight to something built. It is a shape I can relate to in so many levels, from the shape of molecules, to the strongest structure.” 

O’Brien grew up in Freeport, went to the Massachusetts College of Art, and creates sculpture with different types of material. 

Down at the harbor, some clued in right away that the vessel was part of the creative process.

While others were mystified as to its origin and purpose, the oldest lobsterman, who has been around Rockport long enough to know what’s what, said, “I knew it was art.”

Editorial Director Lynda Clancy can be reached at lyndaclancy@penbaypilot.com; 207-706-6657.