Heidi Hammel, American astronomer and academic
Heidi B. Hammel (born March 14, 1960) is a planetary astronomer who has extensively studied Neptune and Uranus. She was part of the team imaging Neptune from Voyager 2 in 1989. She led the team using the Hubble Space Telescope to view Shoemaker-Levy 9's impact with Jupiter in 1994. She has used the Hubble Space Telescope and the Keck Telescope to study Uranus and Neptune, discovering new information about dark spots, planetary storms and Uranus' rings. In 2002, she was selected as an interdisciplinary scientist for the James Webb Space Telescope.

Hammel spends increasing time as a science communicator. She is the 2002 recipient of the Carl Sagan Medal given to a scientist whose communications have greatly enhanced the general public's understanding of planetary science. She was one of Discover Magazine's 50 most important women in science in 2003. In addition to her public-facing work at NASA, she became the executive vice president of the Association of Universities for Research in Astronomy (AURA) in 2010.