Retired astronaut and gun-control activist Mark Kelly on Sunday again urged Congress to address the issue of gun violence, saying survivors of the recent Florida high school massacre calling for a national day or awareness should be a wake-up call on Capitol Hill.

“These kids are incredibly articulate. And some members of Congress are good at not listening. To have high school kids calling for change, it should matter. And I hope in society this will make a difference,” Kelly told “Fox News Sunday” minutes after five students from Florida’s Stoneman Douglas High School said on the show that they are trying to organize nationwide demonstrations for March 24.

“This is a political issue,” he said. “We need to have a vote.”

Kelly is a gun owner but has called for lawmakers to change laws to prevent and stop gun violence in America. He is married to former Arizona Democratic Rep. Gabby Gifford, who survived a January 3, 2007, assassination attempt that resulted in a brain injury.

In the Parkland, Fla., shooting Wednesday, the FBI acknowledged that the agency had received tips about the alleged gunman but that no follow-up occurred. Seventeen people, including 14 students, were killed in the attack.

Kelly said that Florida law enforcement has very little tools to prevent such shootings, but that some states have in fact been “instrumental” in making changes.

“There is a short and abbreviated process to take the firearm away if one alerts authorities that an individual could be a threat,” he said. “That myth you can’t stop it isn’t true.”

Kelly didn’t appear to take an unequivocal stance on whether assault weapons, like the one used in the Florida shooting, are the real problem.

“Most murders, suicides are committed with handguns,” he said. “But when an individual goes into a school or another place with the intent to kill, they can kill a lot of people much more quickly.”