Washington, Feb 21 (IANS/EFE): Fifty years ago, Marine Corps officer John Glenn, wearing a flight suit and helmet similar to those he had worn as a fighter pilot, climbed inside a small capsule and went on to become the first American to orbit the Earth.

The US is commemorating Glenn's exploit with a series of tributes, and Monday night he will attend a dinner in his honour at Ohio State University, where he will take part in a chat with the crew of the International Space Station.

The space pioneer, now 90 years old, said recently that he is surprised that people still take such an interest in those first space flights.

The reason undoubtedly lies in the patriotic significance of his own voyage. Glenn, a veteran of World War II and the Korean War, in just a few hours restored American pride, damaged when the Soviet Union took the lead in the early days of the space race.

The Friendship 7 spacecraft, the size of a Volkswagen Beetle, blasted off from Cape Canaveral, Florida, carried into space by a Mercury-Atlas rocket, and completed three orbits in four hours, 55 minutes and 20 seconds.

After re-entering the Earth's atmosphere, the spacecraft fell into the Atlantic Ocean where it was picked up by a navy ship.

When the hatch opened and the courageous Glenn appeared smiling broadly, he had won one of the most important battles of the Cold War: the image battle.

In the space race, the Soviet Union had seized the advantage when Oct 4, 1957 its 86-kg artificial satellite Sputnik began the first of some 1,440 orbits of the Earth. For three months the satellite continued sending its "bip bip" signal from outer space, a humiliating experience for the US.

Soviets and Americans competed sending capsules into space, in many cases with animals that paid with their lives to satisfy human ambition.

These were followed by mankind's true pioneers outside the Earth's atmosphere.

On April 12, 1962, Soviet fighter pilot Yuri Gagarin, aboard the space capsule Vostok, completed an orbit of the Earth.

The US stepped up its space program and sent two of its men, Alan Shepard and Gus Grissom, on separate missions that did not go into orbit but rather consisted of up-and-down flights beyond the atmosphere that rapidly returned to Earth.

On Aug 6 the Soviets struck again: air force officer German Titov in the Vostok spacecraft orbited the Earth 17 times and was the first human to show that a person can remain more than a single day in space.

Titov, then 26 and still the youngest human ever to travel into outer space, was the first astronaut to directly pilot a spacecraft and took the first photos from orbit.

That was the context in which Glenn became, in the words of novelist Tom Wolfe, "the last true national hero America has ever had".

Glenn went from his career in the military and as an astronaut into politics, and for 25 years represented Ohio in the US Senate.

In October 1998, Glenn became a pioneer once more - at 77 he was the oldest human ever to travel in space, during a mission aboard the space shuttle Discovery.