Former astronaut and Senator John Glenn celebrated the 50th anniversary of his Earth orbit by chatting with the crew on the International Space Station. Mr Glenn, 90, was the first American to orbit the Earth, and later became the oldest person to travel in space. The conversation was part of a larger forum on Nasa\'s future held at Ohio State University. Mr Glenn is only one of two surviving Mercury astronauts, who were the first in the country\'s space programme. \"I\'m talking to you perfectly,\" Mr Glenn said, speaking to Commander Dan Burbank and two flight engineers on board the station. \"It\'s just amazing to talk to you back and forth.\" Mr Glenn piloted Friendship 7 into orbit on 20 February 1962. He circled the globe three times in five hours. In his political career, he served in the US Senate for 24 years, retiring in 1999, and made a bid for president. John Glenn says events of the past should be \"a stepping stone to the future\" During a conversation lasting nearly 20 minutes, the former Ohio senator and space station crew discussed the ongoing research on the station. More than 100 experiments are currently being carried out on board. Nasa administrator Charles Bolden asked the astronauts which experiment Mr Glenn would be charge of on the current space station. Cmdr Burbank suggested research on the station\'s \"regenerative environmental control systems\". That\'s a fancy word for our toilet,\" Don Pettit, a flight engineer admitted. \"He wants to put Senator Glenn busy fixing the plumbing up here.\" \"Exactly what I thought I would get assigned to,\" Mr Glenn said.