"I am having a great time. This is a dream come true, it's an indescribable experience ... I love it," gushed the 59-year-old businessman and grandfather, who paid 20 million dollars and underwent months of tough preparations to make the trip.

The third civilian in history to pay for a flight to space, Olsen is on day four of his ten-day trip, arranged by Space Adventures, the sole space travel agency in operation.

"To me, yes, it's worth the money," Olsen said. "I would not have done it otherwise.

"It's the fourth day and I am really enjoying it and I have fun everyday ... just to look at the Earth from 230 miles (370 kilometers) up is just great. I do think it's worth it.

"As soon as that rocket was launched I was the most relaxed that I have been in two years."

Olsen blasted off from the Baikonur space center in Kazakhstan early Saturday aboard a Soyuz rocket, accompanied by a Russian and an American astronaut.

The only thing that made him nervous was the possibility that he might not get to go afterall, he said.

"When that rocket was pushed off of the ground I just felt a sense of relief and joy," but no motion sickness en route to orbit, he said.

Two other "space tourists" have preceded Olsen in what is becoming a profitable sideline for the Russian space programme: American Dennis Tito in 2001 and South African Mark Shuttleworth in 2002.

During his eight day sojourn aboard the ISS Olsen plans to test out equipment developed by his company, a New Jersey-based firm that makes electronic sensors for military and civilian use.

He will also undertake medical experiments and take photographs.

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