Claudia Joan Alexander (May 30, 1959 – July 11, 2015) was a Canadian-born American research scientist specializing in geophysics and planetary science.

[4] In 1983, Alexander received a Bachelor's degree from the University of California, Berkeley in geophysics,[4] which she thought would be a good background for a planetary scientist.

[7][8] She worked as science coordinator for the plasma wave instrument aboard the Galileo spacecraft[9] before becoming the project manager of the mission in its final phase.

[10] The discovery of the atmosphere, more precisely a "surface bound exosphere", caused scientists to rethink their assumptions that Ganymede was an inactive moon.

[1] Alexander worked as a researcher on diverse topics, including the evolution and interior physics of comets, Jupiter and its moons, magnetospheres, plate tectonics, space plasma, the discontinuities and expansion of solar wind, and the planet Venus.

[1] From 2000 until the time of her death, Alexander served as project scientist of NASA's role in Rosetta, the European Space Agency mission to study and land on comet 67P/Churyumov-Gerasimenko.

[10] On July 11, 2015, Alexander died in Arcadia, California after a ten years battle with breast cancer, aged 56.

[17] In 2002 she earned the Atmospheric, Oceanic and Space Sciences Alumni Merit Award, and she also was a member of their National Advisory Board.

[18] The Claudia Alexander Scholarship was established for undergraduate students at her alma mater in 2007 by her uncle, Jiles Williams.

[23] In 2020, the American Astronomical Society's Division for Planetary Sciences introduced the Claudia J. Alexander Prize awarded to scientists who have significantly advanced the field.