He has spent two decades, and nearly $20 million, in a quest to fly up 40 kilometers to the upper reaches of the atmosphere using a helium balloon, just so he can jump back to Earth again. Now Michel Fournier says he's ready at last to make his "Great Leap."

Depending on weather conditions, Fournier, a 64-year-old retired French Army officer, will attempt what he has dubbed Le Grand Saut (The Great Leap) on Sunday over the plains of northern Saskatchewan, Canada. He will climb into the gondola of a helium balloon that when inflated resembles a giant jellyfish. A two-hour journey will take him to 130,000 feet - higher than any balloonist has been before.

At that altitude he will see the blackness of space on the horizon and the curvature of Earth below, and experience weightlessness. Then he plans to step out of his capsule wearing only a pressurized suit and a parachute, and plunge to Earth in a mere 15 minutes.

If successful, Fournier will fall longer, farther and faster than anyone has in history. Along the way he will accomplish other firsts, breaking the sound barrier and records that have stood for nearly 50 years.