Astronaut Eileen Collins' 7 Year Old Was Afraid Her Mom Would Die in Space: 'I Would Not Wish That on Anybody' (Exclusive)

Collins, who was NASA's first female commander, welcomed two children during her time with NASA

Astronaut Eileen Collins is providing insight into her pursuit of space travel and how it affected her as a parent with two young children, Bridget and Luke Youngs.

The retired NASA pilot and United States Air Force colonel, 68, is the subject of Hannah Berryman’s latest documentary, Spacewoman, which premiered at DOC NYC on Nov. 16.

Collins was the first woman to pilot a NASA Space Shuttle and to command a Space Shuttle mission. She served as the commander of the "Return to Flight" mission in July 2005, following the Columbia Space Shuttle's explosion in February 2003 that killed all seven astronauts on board.

Six months before the Columbia Space Shuttle exploded on its descent back to earth, Collins had had a conversation with Bridget, who was 7 at the time, about the 1986 Challenger explosion.  "And I told her it wouldn’t happen again," Collins tells PEOPLE. "And then just six months later, we had the Columbia accident, and I tried to talk to her about that. She didn't want to talk."

Bridget, now 29, says in the documentary that she believed her mother was going to die: “She would tell me to hope for the best, but expect the worst. I don't think she intended for that to come across as intensely as it did. But a 7-year-old version of myself was like, 'Mom is going to die in space, and I need to be ready for that.' "

Collins, who's been married to Bridget's dad, pilot Pat Youngs, since 1987, recalls her own reaction to her little girl's fears. “I told my daughter, ‘I'm not going to go if I'm going to die. I don't want to die. I'm going to make sure it's safe when I go,’ ” she says. “But she apparently, I learned later, she didn't believe that, and she still had that fear.”

"But honestly," Collins adds, “I think she's much stronger now for that. We have a very open good relationship, I think she's a much stronger person having gone through that. But I wouldn't, I would not wish that on anybody."

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To help Bridget cope with her fears, Collins started a support program because she knew that “the other astronauts' children were feeling the fear seven astronauts just died [in the Columbia explosion].”

She hosted Sunday-afternoon parties for the families, especially the kids. “I would get them to the training sessions where they could see us in the simulator, the airplane, in the pool,” she says. “I wanted to make sure that they all knew each other and had each other with that support. They were so afraid.”

“Every family thinks the explosion on kickoff is going to happen again," Collins says, while noting that the government agency needs to keep pursuing space travel. "We have to go, but we have to be safe."

As she prepared for 2005's "Return to Flight" mission, which would be her final one, she tried to assure her daughter that it would bring her home safely.

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Collins adds that although she and her fellow astronauts are serious, very procedural and mission-oriented, "we also are humans, and we have families," she says. "We have feelings. We have problems. We make mistakes. We try to go through life every day and deal with the problems that keep pushing forward and taking care of our families at the same time."

She says that becoming a mother, although "not easy," was the "best thing" she ever did. "It's hard to be a mom and an astronaut. But it can be done."

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Spacewoman is streaming on the DOC NYC website until Sunday, Dec. 1. Tickets can be purchased here.