It's a sad day for space travel. Sally Ride, the first American woman to ever travel to space, has died at the age of 61 after a bout with pancreatic cancer. She's best known for breaking NASA's gender barrier by flying on Space Shuttle Challenger on June 18th, 1983, but she spent much more of her time guiding our future in space while here on Earth -- she founded NASA's Office of Exploration and directed its early strategy, and she later went on to lead the California Space Institute as well as teach physics at the University of California in San Diego. Her final decade saw her establish Sally Ride Science to encourage students wanting to follow in her footsteps, especially girls. Ride blazed one of the brighter trails in technology, and she'll be missed.

Update: Ride is survived by her same-sex partner of 27 years, Dr. Tam O'Shaughnessy.

[Image credit: National Archives]