What stuck with Sotile, then a teenager in Rochester, New York, wasn't Christa McAuliffe's very public death in a corkscrew-shaped column of smoke that told a live television audience that she and six other astronauts had been killed.

Instead it was memories of McAuliffe's life that endured: a 37-year-old women bubbling with confidence who ventured boldly into a realm that had been largely a man's world. A teacher who had her students read the journals of pioneer women because history text books paid too much attention to men.

"I just always wondered what kind of person she was,'' said Sotile, a former videographer for CNN who had been making short films in Los Angeles with a friend, Mary Jo Godges.

Armed with gumption and bankrolled by credit cards, the pair started shooting a full-length documentary in 2001. It took five years, but they were buoyed by luck, the cooperation of McAuliffe's family and some help from the likes of Carly Simon and Susan Sarandon.

The result is a 75-minute film, Christa McAuliffe: Reach for the Stars, that was to be screened Tuesday night at Framingham State College, McAuliffe's alma mater.

"It brought her alive,'' said McAuliffe's mother, Grace Corrigan, who got an early viewing of the film. "It's was very well done.''

"What a wonderful celebration of her legacy,'' she said.

The showing commemorates Saturday's 20th anniversary of the Challenger explosion, which arrives on Saturday. More than that, it is the completion of a journey for Sotile and Godges, who started filming at Framingham State on the 15th anniversary of McAuliffe's death.

The film tries to shed light on why this high school teacher from Concord, New Hampshire, was picked out of the 12,000 educators who applied for President Ronald Reagan's teacher in space program. It is a portrait of a dynamic woman whose enthusiasm for learning - and life - was infectious, even coming through on old news footage.

"Reach for it,'' McAuliffe tells students on video included in the film. "Push yourself as far as you can.''

At Concord High School, McAuliffe taught economics, law, American history and "The American Woman,'' a course she designed.

Beyond the public persona, the film also gives a glimpse of McAuliffe's life before the space program.

"Christa was so much more than an astronaut running around in a blue suit,'' said Margaret Gilmore, 55, a high school classmate in Framingham.

The documentary includes intimate details, from McAuliffe's baby pictures, to her wedding dress, to images of her own two children, who were 6 and 9 when she died.

There are anecdotes that her students would have savored. McAuliffe wore a strapless dress, for example, to her high school prom, a scandal at her Catholic school in 1966.

Even with the richness of the subject, the documentary was difficult for Sotile and Godges, who had never made a film longer than 10 minutes.

"This was a big story that needed to be told,'' said Godges. "But there were plenty of times when it felt like Renee and I were the only ones who felt like that.''

They were turned down for grants, rejected by funders and their personal credit cards neared their limits.

Then Carly Simon called.

Sotile had written her a letter explaining that McAuliffe had carried a cassette of Simon's music to space because it soothed her. Simon asked about the project, pushed for some narrative details and wrote a song titled "You're Where I Go'' for the film.

Other things started to fall into place. At a film festival in Harlem, Sotile and Godges bumped into actress Susan Sarandon and told her about their project. Sarandon agreed on the spot to narrate the documentary for free.

In the end, Sotile and Godges condensed interviews from about 40 people, amassing 75 hours of new footage.

In large part, however, old footage lets McAuliffe speak for herself.

"I touch the future. I teach,'' McAuliffe said during an interview in the film. "I really appreciate that sentiment. That's going with me.''