VISAR and VenSAR: Two Proposed Radar Investigations of Venus

The last time scientists got a detailed view of the surface of Venus was with the revolutionary NASA Magellan Mission more than 30 years ago. Two new mission concepts under study by NASA and ESA are designed to return to Venus and obtain refined imagery and mapping data to answer some of the major questions concerning the evolution and current geologic activity of Venus. Both these missions would employ synthetic aperture radars to view the surface through the thick optically opaque atmosphere. Each radar design was optimized to meet the science objectives of their respective missions and bring back new data to the planetary science community to unravel why Venus, our twin planet, is so very different than the Earth. This paper discusses the complementary nature of these missions, the design and performance of these two radar instruments, and how each will further Venus and planetary science.