Alexander Loucopoulos wasn't afraid he would drop the ring as he proposed to his longtime girlfriend, but he did have another fear.

"I was afraid the ring would float really far away," the 32-year-old Loucopoulos said.

After all, when he proposed on Saturday to his now-fiancee, Graciela Asturias, they were on a 90-minute zero-gravity flight aboard a Boeing 727 that took off from LaGuardia airport.

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"I asked if she'd marry me, and then the ring just floated in front of her as we floated in zero gravity. It was exhilarating — plus, she was totally shocked," he said.

Loucopoulos said his 27-year-old fiancee is a space enthusiast and that propose in a way that was adventurous.

"I was so surprised," she said. "I'm in total shock."

The trip cost $3,500 per person and was organized by Space Adventures of Virginia, which also arranged for Charles Simonyi's $20 million flight to space in April.

Loucopoulos works as a banker in private equity and Asturias is an architect.

"I would like our 10-year anniversary to be in orbit," Loucopoulos said.