(AP) ? With familiar rituals of grief and a new purposeto honor those who rushed into danger to help, the nation markedeight years since the Sept. 11 terror attacks Thursday, withvolunteers reading the names of the World Trade Center lost. Memorials in New York, at the Pentagon and at the crash site ofUnited Airlines Flight 93 in Pennsylvania all took place under grayskies, and those reading names at ground zero spoke under tents toprotect against rain. "We miss you. Life will never be the same without you," saidVladimir Boyarsky, whose son, Gennady Boyarsky, was killed. "Thisis not the rain. This is the tears." President Barack Obama, observing his first Sept. 11 aspresident, had signed an order declaring it a day of service. Hehad first lady Michelle Obama marked a moment of silence outsidethe White House as a bugler played taps. The president said the nation came together after the attacks,"united not only in our grief but in our resolve to stand up forthe country we love." In Shanksville, Pa., bells tolled for the 40 victims of thefourth hijacked jetliner that crashed there eight years ago. At the World Trade Center site, volunteers - from soup kitchens,advocacy groups, the Red Cross, the United Way - joined relativesof the lost to read the names of those killed in the twin towers. Renewing what has become a poignant tradition, the relativescalled out greetings and messages of remembrances when they reachedthe names of their own loved ones. "We love you, Dad, and we miss you," said Philip Hayes Jr.,whose father, long retired from the Fire Department, rushed to thesite that 2001 morning and ultimately gave his life. Umbrellas bloomed and whipped inside-out at ground zero, wheremoments of silence were observed at 8:46, 9:03, 9:59 and 10:29 a.m.- the precise times that jetliners struck the north and southtowers of the trade center and that each tower fell. "From this day forward, we will safeguard the memories of thosewho died by rekindling the spirit of service that lit our city withhope and helped keep us strong," New York Mayor Michael Bloombergsaid at the ceremony. Vice President Joe Biden, speaking during a break in the list ofnames, told the several hundred gathered that "there's a specialfraternity for those of us who've lost spouses and children."Biden's daughter and first wife died in a 1972 car accident. Biden also joined families who laid flowers in a reflecting poolon the site where the towers once stood. Relatives and friends of victims visited a partially built,street-level Sept. 11 memorial plaza that had not been there a yearago. The twin, waterfall-filled pools surrounded by victims' namesare expected to be built by the attacks' 10th anniversary in 2011. Adding tension to an already emotionally charged day, the CoastGuard conducted a training exercise in the Potomac River near thePentagon, with vessels circling in the water near a bridge whereObama's motorcade had passed. In the confusion, departures from Reagan National Airport werehalted for 22 minutes. They resumed at 10:30 a.m., Federal AviationAdministration spokeswoman Diane Spitaliere said. Federal agentsalso scrambled to the river, said a law enforcement official whospoke on condition of anonymity because the official was notauthorized to discuss the Incident. George W. Bush, whose presidency was defined in part by thatday, had no public appearances planned. A spokesman said he wouldbe working in his office. In a statement, he said he and his wife,Laura, were thinking of the victims and their families. He also honored members of the armed forces and law enforcement."Their courage, service, and sacrifice is a fitting tribute to allthose who gave their lives on Sept. 11, 2001. On this day, let usrenew our determination to prevent evil from returning to ourshores." Stay with News 12 Connecticut throughout the day for local memorials and tributes to those who lost their lives in the attacks.