Aaron Elster, one of a handful of Holocaust survivors whose memories will live on after them thanks to 3-D holograms, died Wednesday, which, at sunset, marked the start of Holocaust Remembrance Day.

Mr. Elster was 86 and had been living in Lincolnshire.

His “story and legacy will live on forever through his interactive hologram,” according to the Illinois Holocaust Museum & Education Center, which announced his death.

Mr. Elster had been a vice president of the Skokie museum, which presents the holograms in its “Take a Stand” program.

“He was so proud to be one of 15 survivors selected worldwide to carry forward survivor stories through conversational holograms,” said museum president Fritzie Fritzshall, also a Holocaust survivor and participant in the museum’s hologram exhibit. “He literally stood taller as his hologram made its worldwide debut at Illinois Holocaust Museum and his image became the face of the museum’s communications campaign.”

Aaron Elster and his hologram. | Illinois Holocaust Museum & Education Center

Smithsonian magazine last year called the display one of “12 Must-See Fall Exhibits Around the World.”

The hologram participants “spent several days in a Los Angeles studio answering upward of 2,000 questions about their Holocaust experiences and related issues before the unblinking gaze of 50-plus cameras,” according to the Illinois Holocaust Museum.

Voice-recognition technology allows the holograms to “respond” to questions from the recorded answers.

Developed with the USC Shoah Foundation, it’s the “first in the world to employ this technology in a permanent exhibition space,” according to the museum.

Mr. Elster was born in the Polish village of Sokolow-Podlaski. During World War II, he lived in the Sokolow ghetto with his parents and two sisters. In September 1942, when soldiers surrounded the ghetto and there was shooting, he recounted that he saw a reaction from his little sister Sara he could never forget.

“The sad look in her eyes stays with me forever,” he said in a museum interview. “Because I was thinking, here’s a 6-year-old little girl, don’t know what’s going on. And then my dad whispers to me, he says, ‘Run!’ ”

Aaron Elster's Holocaust memories and post-war life were told in his book "I Still See Her Haunting Eyes."

Aaron Elster’s Holocaust memories and post-war life were told in his book “I Still See Her Haunting Eyes.”

Young Aaron fled, spotting an old Polish woman who shouted for him to hurry and helped lift barbed wire to free him.

“She smiled at me,” he said. “She says, ‘Run!’ ’’

He fled to a house owned by a Polish couple his parents had previously asked to shelter his sister Irene.

That began his lonely two-year existence as a hidden child.

“The freezing cold and the loneliness and the hunger,” he recalled of that time. “Never took a bath, never cut my hair, never brushed my teeth.”

After nearly two years in their attic, he weighed just 50 pounds.

When the war ended, he lived in orphanages in Poland and displaced-persons camps in West Germany, according to the museum.

In 1947, he arrived in the United States, settling in Chicago. After high school, he worked at a shoe store, O’Connor & Goldberg. He served in the military in Korea and worked for MetLife for 40 years.

Aaron Elster in Illinois Holocaust Museum photo.

Aaron Elster. | Illinois Holocaust Museum

“Out of the 5,000 Jewish people that lived in the town, only 29 people survived,” he said. “Only two children survived on their own: my sister [Irene] and I.”

Afterward, “I dealt with hate, and I had to overcome that,” he said. “Because, as a teenager, I wanted Germany bombed out of existence.”

Mr. Elster volunteered at the museum when it was just a small storefront in Skokie, and he worked to get the permanent museum alongside the Edens Expressway built.

He’d often tell his Holocaust story to police recruits, “helping them understand their responsibilities as law enforcement officers,” according to the museum.

Mr. Elster is survived by his wife of more than 60 years, Jacqueline, sons Steve and Robert and three grandchildren. A service is planned for 1 p.m. Monday at Shalom Memorial Park in Arlington Heights.

In 2015, he wrote about his goals: “When I speak to children every day at the Illinois Holocaust Museum & Education Center, I ask that they take away two ideas from my story. First, you must believe in yourself. It is essential to love, appreciate and respect yourself above all. With this, you will discover that you are stronger and smarter than you think you are. Second, I want children to learn that prejudice and indifference will only lead to hatred and violence that will impact innocent lives, including their own. As the decision-makers of tomorrow, our children must engage in the creation of new stories that speak to a more hopeful world that doesn’t echo our past.”