This Dec. 2012 photo provided by Jonathan Clark shows Dr. Jonathan Clark, husband of Columbia astronaut Laurel Clark, stands with his son, Iain Clark, 18, in Arizona. Clark's wife and six other astronauts, Commander Rick Husband, co-pilot William McCool, Kalpana Chawla, Michael Anderson, Dr. David Brown and Israeli Ilan Ramon, were killed in the final minutes of their 16-day scientific research mission aboard the space shuttle Columbia on Feb. 1, 2003. Iain is set to graduate this spring from a boarding school in Arizona; he wants to study marine biology at a university in Florida. (AP Photo/Jonathan Clark) This Dec. 2012 photo provided by Jonathan Clark shows Iain Clark at an indoor skydiving center in Denver. Clark's mother, Dr. Laurel Clark, and six other astronauts, Commander Rick Husband, co-pilot William McCool, Kalpana Chawla, Michael Anderson, Dr. David Brown and Israeli Ilan Ramon, were killed in the final minutes of their 16-day scientific research mission aboard the space shuttle Columbia on Feb. 1, 2003. Iain is set to graduate this spring from a boarding school in Arizona; he wants to study marine biology at a university in Florida. AP Photo/Jonathan Clark (AP) - He was just 8 when NASA lost the space shuttle Columbia and he lost his astronaut mom. Now, 10 years later, Iain Clark is a young man on the cusp of college with a master's rating in scuba diving and three parachute jumps in his new log book. His mother, Dr. Laurel Clark, loved scuba and skydiving. So did her flight surgeon husband and Iain's dad, Dr. Jonathan Clark, who since the Feb. 1, 2003 accident, has been a crusader for keeping space crews safe. One became a fighter pilot in Israel, just like his father, and also died tragically in a crash. The oldest son of the pilot of Columbia is now a Marine captain with three young children of his own. The commander's daughter is a seminary student. It's tough losing a mom, that's for sure. I think Iain was the most affected," said Clark, a neurologist. My goal was to keep him alive. That was the plan. It was kind of dicey for a while. There was a lot of darkness - for him and me. Clark's wife and six other astronauts - Commander Rick Husband, co-pilot William McCool, Kalpana Chawla, Michael Anderson, Dr. David Brown and Israeli Ilan Ramon - were killed in the final minutes of their 16-day scientific research mission aboard Columbia. The space shuttle, with a wing damaged during launch, ripped apart in the Texas skies while headed for a landing at Kennedy Space Center. NASA will remember the Columbia dead at a public memorial service at Kennedy on Friday morning. Clark, now 59 and long gone from NASA, said he turned to alcohol in the aftermath of Columbia. If it wasn't for his son, he doubts he would have gotten through it. "He's the greatest kid ever," Clark said in a phone interview from Houston with The Associated Press. He cares about people. He's kind of starting to get his confidence, but he's not at all cocky. "His life is like about as idyllic as you could imagine, considering all ... he's been through," said Clark, who is still protective of Iain's privacy. He would not disclose where Iain attends school, but he did provide a few snapshots. Mother and son were extremely close. After the accident, Iain insisted to his father: "I want to invent a time machine," If he could go back in time, the child reasoned, he could warn his mother about the fate awaiting her. "He asked me why she didn't bail out, that kind of stuff, because he knew she had been a parachutist," Clark recalled. Father and son were among the astronauts' families waiting at the Kennedy runway for Columbia that early Saturday morning. Once it was clear there had been trouble, the families were hustled to crew quarters, where they got the grim news. Rona Ramon's sharpest memory about that fateful Feb. 1 is how "the joy and the longing" to see her husband return from space turned so quickly into anguish. I just looked up at the sky and said, 'God, bring him back to me.'  Her husband, already a heroic military pilot, became Israel's first spaceman on the flight. Clark hastily came up with a plan: Disappear with his son as soon as they got back home to Houston. Grab the dog, the car and as much money as possible. Then, "drop off the grid." But that didn't happen. A few years went by before father and son finally made their escape. Clark bought a house in Arizona, keeping a small apartment in Houston as he went from working for NASA at Johnson Space Center, to a teaching job at Baylor College of Medicine and an adviser's position at the National Space Biomedical Research Institute. Clark won't divulge his exact whereabouts, even now. He moves every few years. He has a girlfriend, but doesn't see himself remarrying. "I don't ever want to go through losing a wife again," he explained. Clark remains bitter over the "really bad people" who came after him in Houston for money and favors, spurred by NASA's $27 million settlement in 2007 with the Columbia families. There was a lot of grief. There was a lot of sorrow. There was a lot of destructive behavior. There were a lot of people taking advantage of you," he said. But Clark holds no grudges against NASA, neither the agency as a whole nor the managers who, during the flight, dismissed concerns from low-level employees about the severity of damage to Columbia's left wing. It was gouged by a piece of insulating foam that peeled off the fuel tank at liftoff. Clark learned of the foam strike during the mission, while working a shift in Mission Control. Like so many others, Clark wishes he'd done something. But no one knew during the flight how badly Columbia was damaged. And no effort was made to find out while there still was time to consider what would have been a risky rescue attempt by another shuttle. Surviving the actual breakup, during re-entry, was deemed impossible by all involved. At 210,000 feet going Mach 15, it was "much, much worse than anything we had ever planned for," former NASA shuttle manager and flight director Wayne Hale wrote in his blog earlier this month. For four years after the Columbia accident, Clark assisted a NASA team that looked into how the astronauts died and how they might have survived. For Clark, it was about "trying to find something good out of something bad. I kind of threw my heart and soul" into crew survival issues and, most recently, the faster-than-the-speed-of sound, stratospheric jump by Felix Baumgartner. Clark was the medical director for the Red Bull-sponsored feat last fall in New Mexico. The tragic end to NASA's 113th shuttle flight prompted President George W. Bush to take action. He announced in 2004 that the three shuttles left would stop flying in 2010 once they finished delivering pieces of the International Space Station. The shuttles resumed flying with new safety measures in place and eked out an extra year, ending on No. The only way out of the Columbia darkness, for Clark, has been to move forward. "It doesn't mean I don't miss Laurel or have remorse about what happened," he said. But you cannot be living in this kind of grief-stricken mode. ... Laurel would kick my ass if that happened to me. The shuttle commander's widow, Evelyn Husband Thompson, finally feels free to start giving back, now that her youngest, Matthew, is 17. She wanted to focus first on her two children and then on her marriage five years ago to Bill Thompson, a widower she met through church. Bill provided the crucial male role model that Matthew so desperately needed following the accident, she said. Now, his mother said, "he enjoys his private life." It was tough. Overnight, my children were thrust into this international stage," Thompson said. Having the last name "Husband" drew grief-stricken stares for the longest time in Houston, home to Johnson Space Center. "With the mercy of time, people really don't recognize it as much as they once did," she said. Her new passions, each purposefully low-profile: her neighborhood YMCA where Husband once coached children, a ministry for widows at her church, and a Christian organization that helps fatherless boys. "These three areas right now just fit me to a T, and I know that they would really please Rick," Thompson said in a phone interview Tuesday. "We just still miss Rick so much," she said. The sweet part of it is that we have made it 10 years, that God has been faithful in our lives, and we have been able to find joy in the midst of a lot of sorrow. Daughter Laura, 22, is working on a master's degree in theology. Matthew is a high school sophomore. The entire family, as well as close friends, will gather at Kennedy for Friday's memorial service, which also will honor the seven astronauts who perished during the Jan. 28, 1986, liftoff of Challenger and the three killed on the launch pad in the Jan. 27, 1967, Apollo 1 fire. Thompson is a featured speaker. Anderson's widow, Sandra, also plans to attend. The two women, who attended the same church with their late husbands, remain close. The rest of the Columbia families have drifted apart, Thompson noted, but they all have a common goal. "Try to find a way to have beauty come out of the ashes," she said. You just want to feel like you're making a difference. She is one of two Columbia spouses who have written memoirs about their loved ones. Kalpana Chawla's husband, Jean-Pierre Harrison, who also has remarried, published a biography titled "The Edge of Time" in 2011. Clark is in Israel this week, taking part in an annual space conference held in honor of Ramon. Of all the Columbia families, he feels closest to Rona Ramon. She became a grief counselor after her second family tragedy. The Ramons' oldest of four children, Asaf, died at 21 when his jet crashed in an Israeli training accident in 2009. Her daughter is 15. One of McCool's three sons is also in the military, a captain in the Marines. Reminders of Columbia's dead are everywhere - including up in the sky. Everything from asteroids, lunar craters and Martian hills, to schools, parks, streets and even an airport (Rick Husband Amarillo International Airport) bear the Columbia astronauts' names. Two years ago, a museum opened in Hemphill, Texas, where much of the Columbia wreckage rained down, dedicated to "remembering Columbia." About 84,000 pounds of that wreckage - representing 40 percent of NASA's oldest space shuttle - are stored at Kennedy and loaned for engineering research. The tragedy has made Clark and his son more spiritual. He's a really good kid and I wonder - you always wonder - would he have been this way if he hadn't lost somebody so dear in his life. Maybe this was Laurel's gift to him. AP writer Aron Heller in Jerusalem contributed to this report.