The Titanic submersible passengers have died. It's OK to grieve.

The worst has come to pass. The five people who went missing in the submersible exploring the Titanic wreckage have died, according to authorities.

"This is a very sad time for the entire explorer community, and for each of the family members of those lost at sea," OceanGate, the company behind the mission, wrote in a statement. Debris from the submersible, known as the Titan, was found Thursday.

The news has captivated the nation – so much so that these deaths are likely to feel personal. If you feel like you're grieving people you don't know, it's a common-enough phenomenon that there are terms for it: collective and public grief. And it's OK to feel that way.

"Collective and public grief, as I call it, is always unique in how we attach," says David Kessler, grief expert and founder of Grief.com. "There's people who are watching this story, ... are getting attached. Who are these people? What's going on here?"

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Many have parasocial relationships with those in the public eye, be it celebrities, politicians, news anchors. You feel close to them like they're your friend or relative. Similar relationships can develop watching traumatic situations unfold in the news.

"We've been very unconsciously getting involved in this rescue mission with these people," Kessler says. Many people had expressed concern for the health and safety of the passengers. Others took an opportunity to pounce on the wealthy. And a lot more dashed to design the perfect meme.

But everyone knew death was a possibility. People began thinking about dying once this deep-sea story first broke. They may not want to – but how could one not examine their own mortality in a situation like this?

"No one wants to sit around a water cooler and say, 'Let's discuss our deaths,'" Kessler says. "But we can discuss, 'Oh my gosh, what if our apartment collapsed? Oh, my gosh, what if we were those people?' We know how to discuss them. There's safety for us in exploring others' tragedies."

If you're trying to comfort someone going through loss, don't try to minimize it or put a timetable to the grieving process.

"There is no limit to grief and because it is a cycle or process, it will continue as long as it needs to for the person who is experiencing it," Shavonne Moore-Lobban, a licensed psychologist, previously told USA TODAY.

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Just because this grief doesn't match how one might grieve someone close to them doesn't make it any less real.

"It's a fascinating thing that people don't realize we really can grieve people we didn't know," Kessler adds. "And it doesn't mean we're going to grieve them like our spouse or mother, father, or sister or child, but we will grieve them. And we will also live with the disappointment of we always want to know if something bad happened, we could get saved."

Perhaps this could serve as an opportunity to widen discussions on grief.

"We have a relationship with death that we don't quite know how to explore as a society," Kessler says. "I always tell people the death rate is 100%. So we know we're all going to die someday, intellectually, but we don't know, is death the great enemy? Is it the great comforter, when we're in pain? We sort of don't know how to hold it. And in a strange way, when people's lives are threatened, it's this vicarious way that we explore, 'Oh, my gosh, what if it was us? And are they going to get saved? Are we going to get saved when we need it?'"

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This article originally appeared on USA TODAY: Titanic submarine passengers are dead. Why grieving is OK.