Yesterday, the European Space Agency announced an Open Access policy for images and data under a Creative Commons BY-SA license. ESA has made various moves toward making data and images more open in the past, but this announcement is a major milestone for the organization’s commitment to openness.

Previously, ESA released individual images under Creative Commons licenses, but this organizational shift marks a substantial change in the way that ESA shares with the world. The choice of CC BY-SA clears ESA’s content for use in larger repositories like Wikipedia (and Wikimedia Commons), as well as by any individual member of the public. It also reaffirms the organization’s commitment to widely sharing open data and imagery across the web.

“This evolution in opening access to ESA’s images, information, and knowledge is an important element of our goal to inform, innovate, interact, and inspire in the Space 4.0 landscape,” said ESA Director General Jan Woerner in the organization’s announcement about the new policy.

Because many ESA images are created in collaboration with partners, this first release under CC BY-SA is limited to content that is completely owned by ESA (or for which any third-party rights have been cleared). The organization plans to release other sets of images under CC BY-SA in future phases of this new Open Access project.

The full repository includes the Rosetta images, “Sounds from Space,” Earth Observations from the agency, Hubble images and video, and the Planetary Science Data Archive.

Ground Control to the ESA, you’ve really made the grade! Check out the entire archive.