Launched in 1990, the NASA/ESA Hubble Space Telescope remains the premier UV and visible light telescope in orbit. With well over 1.6 million observations from 10 different scientific instruments, the ESA Hubble Science Archive is a treasure trove of astronomical data to be exploited.
European Space Agency, Noll comma Keith S., 1997, 'COMPOSITION OF DARK MATERIAL ON IAPETUS CYCLE4 - MEDIUM', 1.0, European Space Agency, https://doi.org/10.5270/esa-h4ndba3