Oil spills are a critical form of environmental pollution that have far-reaching negative impacts. They severely degrade marine ecosystems, introducing toxic chemicals into the oceans and harming sea life. They also have significant financial impacts through the diminishment of ecotourism as well as the killing of commercially viable species. Despite these negative impacts, oil spills are notoriously difficult to track and monitor given the general lack of surveillance over the vastness of the Earth’s oceans. Space-based technologies are evolving as a tool to aid in the detection of oil spills worldwide. Two primary technologies have been optimized for oil spill monitoring: optical satellite imagery and synthetic aperture radar (SAR). Optical satellite imagery functions somewhat like taking a photograph of the Earth’s surface and requires clear skies and daylight to produce imagery. SAR imagery, on the other hand, relies on microwaves to produce images, and therefore can function regardless of weather, as well as at night. The combination of these two technologies has allowed scientists an increased ability to monitor where and when oil pollution is happening, providing an eye-in-the-sky to survey marine activities. While these space-based technologies are aiding in the detection of a variety of oil spill incidents, they are particularly helpful to monitor the illegal dumping of oil and effluent from shipping vessels as ships are no longer able to dump oily bilgewater into the ocean under the veil of darkness. Unfortunately, the enforcement of environmental and marine law remains an issue and ships are rarely prosecuted. It will be important for space-based technologies to continue to evolve and provide evidence of marine pollution in the effort to provide protection for Earth’s marine ecosystems.