The realization that tragedy was back swept over people in soft ripples on a dreary weekend morning.

Banker David Vardeman turned on his television and momentarily thought he must be watching a replay of the space shuttle Challenger exploding in 1986.

Michael Blanke got to the Smithsonian's Air and Space Museum and headed for the large-screen television that for 16 days had shown images from the shuttle Columbia. But instead of the post-landing footage he expected from Cape Canaveral, there was a grave image of NASA employees milling silently in front of computers at Mission Control.

And at Union Station, passengers from arriving trains wondered why three park rangers were methodically lowering the 55 state and territory flags and the three large U.S. flags outside to half-staff.

"We knew something was bad," said Tess Shatzer, 43, of Mason, N.H., as a chill wind slapped the wires against the metal flagpoles.

Yesterday was another day that people will remember years from now with clarity, recalling exactly how they learned the news.

Some were jolted by the disaster during a flight they had paid so little attention to that they had not even realized a shuttle was in the air.

Others had followed the flight's progress closely, feeling a personal attachment to the seven crew members that ultimately served to heighten their grief over the catastrophe.

That was especially true in communities where an astronaut symbolized dreams.

In the Indian community, people felt a reflected pride in the accomplishments of engineer Kalpana Chawla, who had immigrated to the United States from India.

Many in the Jewish community took particular interest in Israel's first astronaut, Col. Ilan Ramon, the descendant of Holocaust survivors and a war hero who carried a Torah scroll and an Israeli emblem into space with him.

In the African American community, Air Force Lt. Col. Michael P. Anderson, the payload commander, was one of a handful of black astronauts in the space program and a role model.

But nowhere was the loss more keenly felt than in a living room in Washington, Va., in Rappahannock County, where Paul and Dorothy Brown sat watching coverage of the reentry of the shuttle carrying their son, Navy Capt. David M. Brown.

When the announcer said the National Aeronautics and Space Administration had lost contact with the shuttle, Dorothy Brown said, they initially thought there was some technical difficulty. Then the telephones started ringing with calls from friends and family who were at Kennedy Space Center in Florida. They began to fear the worst.

"When they told us that NASA was moving them to another building, that's when we knew," Brown said in a phone interview yesterday.

Mentioning Brown, a graduate of Yorktown High School in Arlington and the College of William and Mary, Gov. Mark R. Warner said yesterday that the loss of Columbia had particular meaning for Virginia residents.

"The commonwealth has a long association with the space program through research programs in many of our universities and the NASA Langley research facility, and I know that all Virginians join me in expressing sympathy to the families and friends of the crew members and to everyone who serves in NASA," he said.

Word of the tragedy blotted out much talk about other issues, such as a potential war with Iraq, and curtailed festive activities.

Leon Williams, 48, who heard about the disaster while shopping in Adams Morgan, said it was a wake-up call to keep in mind while debating whether to wage war in Iraq.

"We've been focusing on another country, and that's what happens: You lose perspective of what you're supposed to be doing over here. You're caught off guard," Williams said.

The India Sari Palace in Langley Park was cloaked in gloom, a stark contrast to the customarily festive swirl of shopping during a season when many immigrants take advantage of cheaper flights between the United States and the Asian subcontinent. Throughout the day, customers echoed the same question as they came in the door, owner Lakshman Nandwani said.

"Everybody, when they walk into the store, they say, 'Did you hear?' " he said.

Kalpana Chawla was "the dream of young India," said Anil Chowdhry, an official with the Indian Embassy in Washington. "She represented the best traditions of modern India."

Krishna Kumar, 30, a lawyer from Arlington who heads the Indian-American Policy Institute, said: "It was wonderful to see how someone could obviously succeed like her. . . . It was a big element of quiet pride" for Indians here.

At the Israeli Embassy in the Van Ness neighborhood in Northwest Washington, visitors stopped by with flowers to pay tribute to the lost Israeli. One mourner left behind a yahrzeit candle in memory of the dead.

A typewritten note said, "Ilan Ramon a hero to all Americans. Thank you for your courage."

In life, Ilan Ramon had been a symbol of hope for an embattled nation and its supporters. It made his death to those who followed his journey to the stars all the more bitter.

"It is fair to say that this was one of the brighter, more optimistic events of recent months in Israel, and that makes the pain of this loss even keener to the nation and to those who care about Israel," said David Saperstein, a rabbi and director of the Religious Action Center of Reform Judaism.

"It's an especially extreme sense of loss to all who love Israel. This was an achievement of enormous pride and meaning in Israel and people who care about Israel."

Dalya Luttwak, an artist from Chevy Chase who was born in Israel, said Ramon was among her nation's best and brightest. "He actually represented everything that is so wonderful about Israel in my eyes," she said.

Anderson held equal esteem for many African Americans, who mourned the death of a man who had met his highest aspirations.

"As we celebrate Black History Month and how far we have come as a people, once again tragedy has struck one of our most cherished heroes who made the ultimate sacrifice, who now will go down in history with our other heroes," said the Rev. Harry L. Seawright, pastor of Union Bethel AME Church in Brandywine.

Some parents managed to turn the day's event into a teachable moment, striving to help their children better understand the grief around them.

John Crum of Mitchellsville was at home with his 11-year-old son, Jonathan, when news of the Columbia was broadcast. The father took his son to Goddard Space Flight Center in Greenbelt hoping to put the tragedy into perspective.

"I've just never heard of anything like that going on," said Jonathan, who was born about six years after the Challenger exploded. "I just wanted to see what was happening."

At 11 a.m., flags at Goddard were lowered to half-staff, while inside the NASA Visitors Center a large-screen television that usually shows educational videos about space was broadcasting news of the accident.

Many adults struggled with their emotions. Alan Williams, a volunteer tour guide at the center, said it would take a while for him to digest the tragedy.

"We'll figure it out eventually," he said. "But it's going to be tough to process the whole thing."

At the Air and Space Museum, about 100 visitors gathered before a television to listen to a live 1:20 p.m. news briefing by a NASA administrator.

James Fulton, a retired NASA employee of 32 years who volunteers as a docent for the museum, mingled with the crowd and answered questions. Fulton worked as an administrator for Mission Control when fire broke out in the cockpit of Apollo 1 during a launchpad test in 1967.

"To lose communications and not be able to regain them immediately, that means something very, very bad has happened," Fulton told bystanders. "The networks are saying contingency plans have been put into effect. I know what that means -- it means everyone has a responsibility to ensure no information is lost."

Eventually, curiosity gave way to sorrow. When NASA Administrator Sean O'Keefe talked about the crew members' families, some of the bystanders wiped away tears.

"I think a lot of people don't realize the risks people take when they go up on one of these missions," Mary DuMont said at the museum. "We forget about that. This is a reminder."

Many Americans sought solace in faith.

At Temple Sinai, a Jewish Reform congregation in Northwest Washington, Rabbi Fred N. Reiner recited the kaddish, a prayer for the dead. At Washington National Cathedral, the names of the seven astronauts were read at the noon Eucharist.

The bishop of the Episcopal Diocese of Washington, the Right Rev. John Bryson Chane, asked the clergy and congregation to remember the astronauts and their families in their prayers today.

Chane said he wants congregants "to remember that these astronauts gave their lives in the exploration of things dreamed of but not yet realized."

Staff writer Clarence Williams contributed to this report.

At the National Air and Space Museum, visitors gather near a large-screen television to watch coverage of the Columbia disaster.Children try to get a closer look at a model of Columbia at the Air and Space Museum.Flags at the base of the Washington Monument flutter at half-staff, lowered after the shuttle Columbia disintegrated, killing seven aboard.