EASTHAM, Mass. (AP) -- A century after Guglielmo Marconi ushered in the era of wireless communications, his daughter marked the centennial Saturday by greeting astronauts from close to the same spot where her father sent a historic radio transmission across the Atlantic.

``In this same spirit of his achievement, and also from Cape Cod, I send this wireless greeting to you in space. Cordial greetings, and good wishes,'' Princess Elettra Marconi told Kenneth Bowersox, commander of the international space station.

``It is amazing how far society and radio communications has come in the last 100 years. It is wonderful to hear your voice across the radio waves,'' Bowersox told the princess, who spoke from an auditorium filled with about 200 people.

The radio transmission was sent from the eastern end of the cape to Nova Scotia to Cornwall, England. In his message, Roosevelt called the achievement a ``wonderful triumph of scientific research and ingenuity.''

Marconi, who won the Nobel Prize for physics in 1909, had previously delivered messages over shorter distances, and transmitted the letter 'S' in Morse code across the Atlantic, but the 1903 transmission solidified the legitimacy of radio.

The message from the princess, who is in her early 70s and gained her title by marrying an Italian nobleman, was part of a week of centennial events culminating Saturday night with the worldwide transmission of a message from President Bush.

``By inventing the first practical system of wireless telegraphy Marconi pioneered international communications and opened the door for technological advances that have improved the lives of countless Americans and people around the world,'' Bush said.

Members of the Marconi Radio Club staged a weeklong radio marathon, communicating with other amateur radio enthusiasts around the world from an old Coast Guard post not far from the site of Marconi's original station. The radio hams expect to log more than 10,000 transmissions by week's end.

The site of the 1903 transmission is under water because of erosion. The National Park Service has placed a replica of Marconi's original radio transmitter on the bluff above.