Senator and astronaut John Glenn unveils the star for New York's Rockefeller Center Christmas tree today. Glenn appeared in his second Manhattan ticker-tape parade.

NEW YORK - In a swirl of confetti and shredded paper, an older, grayer John Glenn made his second trip through Manhattan's Canyon of Heroes in a parade Monday saluting his return to space 36 years after he became America's first man in orbit.

Dressed in a blue flight suit and perched in an open convertible beside his wife, Annie, the 77-year-old pioneering astronaut was applauded by a crowd of thousands who lined the 14-block route along the office towers of lower Broadway.

"It truly rates the word awesome,'' Glenn said at a ceremony after the parade at City Hall, where he and other crew members of the shuttle Discovery were presented with keys to the city by Mayor Rudolph Giuliani.

Glenn's first ticker-tape parade on March 1, 1962 after his Mercury flight is considered the largest ever in New York. An estimated 3,474 tons of confetti and ticker-tape rained down along a seven-mile route.

Even boosted by noontime crowds from Wall Street, the turnout Monday in honor of his shuttle flight was sparse by New York standards and spectators along a route less than a mile long were surprisingly restrained.

A parade honoring the World Series champion Yankees attracted an estimated 3.5 million people on Oct. 23. Police said Glenn's parade was attended by 500,000 - a figure that appeared generously inflated.

The 1962 celebration "was more enthusiastic - a lot more people,'' said Myrtemina Lasalle, 58, who as a young newlywed attended Glenn's first parade and came from her Brooklyn home for his repeat trip Monday.

Gretel Enck of Brooklyn, 30, looked over the thin crowd and said too many Americans take the achievements of the space program for granted. Glenn's Discovery trip restored some of the luster - even if temporarily, she said.

"It's become so everyday, so ordinary, nobody cares,'' she said.

At City Hall, where artwork by Peter Max adorned the portico and red, white and blue bunting fluttered from the windows, former CBS anchorman Walter Cronkite said of Glenn, "He was a hero to us then, and he's a hero to us now.''

Glenn told the crowd, which included many schoolchildren, that he hoped the Discovery flight would inspire another generation - as well as the elderly - to reach for the stars.

Holding his key to the city, Glenn said the tribute "unlocked the hearts and souls of the people of New York toward us, and we appreciate that very, very much.''

Glenn began the day with Giuliani, unveiling a Moravian-style star for the Rockefeller Center Christmas tree. After that event, Glenn recalled the 1962 parade, saying, "It was just so enormous. I remember just a blizzard of paper. You could hardly even look up without getting something in your eye.''

Glenn, the other Discovery crew members and the mayor then attended an invitation-only breakfast for 500 guests at the Museum of Natural History. The other shuttle crew members, who traveled in floats along the parade route, are Cmdr. Curtis Brown, Steven Lindsey, Scott Parazynski, Stephen Robinson, Pedro Duque and Chiaki Mukai.

Glenn's chauffeur for Monday's parade was police Officer Thomas Halinan, the son of former Officer Kevin Halinan, who drove Glenn in the 1962 parade. The older Halinan rode along in the car for good measure.

Glenn, who retires from the U.S. Senate next month, joins a list of individuals and sports teams honored with more than one ticker-tape parade. Others given that tribute include the New York Mets and New York Yankees, former Ethiopian emperor Haile Selassie, Dwight Eisenhower and Amelia Earhart.

World leaders and others were routinely given ticker-tape parades in the city, a practice that was curtailed after 1965. Recent honorees include Nelson Mandela, Pope John Paul II and the Gulf War veterans.

Ticker tape, the paper ribbon on which telegraphic tickers print information, has given way to shredded computer paper, confetti and toilet paper tossed from windows along the route.