The first of Christa McAuliffe's lost lessons finally was released from space Tuesday, 32 years after she died aboard Challenger.
NASA and the Challenger Center for Space Science Education posted a video of astronaut-educator Ricky Arnold performing one of McAuliffe's experiments aboard the International Space Station.
McAuliffe, a high school social studies teacher from Concord, New Hampshire, never got to teach from space. She perished during the launch of shuttle Challenger on Jan. 28, 1986, along with her six crewmates.
June Scobee Rodgers, widow of Challenger commander Dick Scobee and the Challenger Center's founding chairwoman, offered an emotional thank you to Arnold during a live TV linkup. She spoke from Arlington, Virginia, where dozens of the center's educators and directors gathered for an annual meeting. Several of them took turns asking Arnold about teaching and life in space.
"From the day after the Challenger accident when I knew that NASA would continue the mission, I prayed that we could continue the education mission," Rodgers, an educator herself, told Arnold.
Many teachers have worked to make this possible, she noted, "but you give us the culmination of the dream for Christa's lessons to come to life."
The first 4 ½-minute lesson demonstrates how a mixture separates into its individual parts. Arnold uses chromatography paper, water, food coloring and a felt pen. Another lesson will be posted online in a few weeks. Altogether, about four are planned, including demonstrations of fluids and bubbles in weightlessness, and Sir Isaac Newton's laws of motion.
Arnold, a former science teacher, said it's been "an incredible honor" to complete McAuliffe's lessons. In orbit since March, Arnold is due to come home in October.
Astronaut-educator Joe Acaba also carried out some of McAuliffe's planned lessons, before returning to Earth in February.
NASA calls their back-to-back missions a "year of education on station."
Explore further: Christa McAuliffe's lost lessons finally taught in space