On newspaper racks Tuesday, 9/11 was markedly absent from the front pages of the New York Times and the New York Post.

“The pain, the outrage, the loss — these never fade,” wrote the Times public editor Margaret Sullivan. “The amount of journalism, however, must.”

On the 11th anniversary of a tragedy, many Americans arose not remembering. It was another day of making coffee, packing sandwiches for kids’ lunches, dropping off the dry cleaning before work. Memorial ceremonies, too, were fewer and simpler than in the past.

It is natural for time to heal. Natural, too, for people to want to move on.

But there was one place where the tragedy was hard to miss — on social media.

Twitter, Facebook, Google Plus and Instagram did not exist 11 years ago. 9/11 did not transpire in social media real time as many news events today do. But memories of that horrific day were kept alive Tuesday via smartphone, tablets and computers.

Social media was a way for people to express their emotions when there were fewer physical ways to do so, said Robin Carey, CEO of Social Media Today.

Maybe you weren’t going to the local remembrance and hear the bells toll at 8:46 a.m., the time American Airlines Flight 11 slammed into the North Tower. But you could get out your phone and Tweet what you remembered about that moment.

“There’s a lot of trending now on Twitter which shows it’s a lot more durable than the media would believe at this point,” Carey said.

Among trending topics Tuesday were WTC, 11S, Remember911, Iraq, New York City, R.I.P and Bush.

The New York Police Department memorialized fallen officers through a Twitter campaign with the hashtag neverforget. Each tweet linked to a poignant Facebook page about an officer. It was the social media version of a reading of names.

Some people tweeted about where they were when they first got news about the attacks.

@mikestuchbery: “This time 11 years ago I was working on a presentation for a uni English course. It never happened.”

Facebook users posted photos of how Lower Manhattan looked then with the Twin Towers and how it looked Tuesday morning.

Others posted sayings such as “Never Forget,” and still others, their remembrances of people who perished that day.

“9.11 Day,” a movement built on people remembering through positive action, gained traction with more than 330,000 Facebook likes.

The 9/11 Memorial has a Google Plus page with more than 57,500 members and a Twitter account — @Sept11memorial — with more than 19,000 followers.

There were Twitter and Facebook gasps at realizing it has already been 11 years and that some young soldiers fighting in Afghanistan were in second grade when the Twin Towers came crashing down.

“If the public comments did not exist, then you would not have the same attention on 9/11,” said Sanford Dickert, a social media technology expert.

“There are so many moments we have let go because in the mental consciousness of our society, sometimes we forget things,” he said. “Social media provides the opportunity to find those issues you are concerned about.”

Brian Monahan, a sociology professor at Pennsylvania’s Marywood University, said social media helps Americans remember 9/11 in an anniversary year that is not a milestone, such as the 10th, 20th or 25th.

It also provides ways to remember events other than the structured process of scheduled memorials, said Monahan, who has studied coverage of 9/11. There was a proscribed way before of how to be solemn. The symbolism went through official channels.

“It was an informal process but it was structured,” he said.

Social media takes all the barriers away.

The conversation about 9/11 is also different now on Twitter and Facebook, especially after the killing of Osama bin Laden, Monahan said.

“There was only one way to talk about 9/11 and that was tragedy,’ Monahan said. “But now it’s about core American values.”