Golden anniversary of John Glenn orbiting the Earth celebrated at Great Lakes Science Center

CLEVELAND - Fifty years ago on February 20, 1962, Ohioan John Glenn made history in becoming the first American to orbit the Earth. Monday, Glenn, who is now 91 years old, was celebrated as not only a history making astronaut but a courageous explorer and American hero.

NASA Space Shuttle astronaut Greg Johnson told the crowd at the Great Lakes Science Center in Cleveland that Glenn's chances of surviving the high risk mission were just one in six.

"John Glenn had the courage to do something that they had no idea what the outcome was going to be," said Johnson.

After Glenn orbited the earth three times that day, elation quickly turned to concern that the heat shield on Glenn's capsule, Friendship 7, would falter during re-entry.

"The heat generated for re-entry is up to 3,000 degrees," said Johnson.

But drama turned to celebration when Glenn landed safely in the ocean -- America cheered, and Ohio had a hometown hero.

Seven years later, another Ohioan, Neil Armstrong, was the first man on the moon.

Johnson told the crowd Glenn's bravery laid a lot of the foundation that led to space shuttle missions and today's International Space Station.

Intrigue about history and excitement for the future attracted many families to the Great Lakes Science Center in Cleveland on this the 50th anniversary of the day Glenn spent 4 hours and 36 minutes in orbit.

"It's an incredible day for Ohio and learning about the history of Ohio with my two little boys and teaching them about the history is real important to me," said Katie Kowza.

After his mission to space, Glenn spent 14 years as a United States Senator.