Introduction: Planetary impacts that occur at the lowest impact angles with respect to horizontal produce craters that are elliptical in planform with the long axis oriented in the downrange direction. Experimental hypervelocity impacts into a strengthless medium suggested that craters should become elliptical for impact angles < ~5 ̊ [1]. Bottke et al. [2] conducted surveys of the crater popula...

Introduction: The subsurface structure of impact craters on the Earth is typically accessible only through drill core data and geophysical surveys [e.g., 1, 2]. On Mars, some 20 impact craters have been identified in this study that have been cut by a combination of tectonic activity and erosion and are partially exposed in cross-section. Many of these cut craters lie along the walls of the Val...

The Lunar CRater Observation and Sensing Satellite mission (LCROSS) impacted the moon in a permanently shadowed region of Cabeus crater on October 9th 2009, excavating material rich in water ice and volatiles. The thermal and spatial evolution of LCROSS ejecta is essential to interpretation of regolith properties and sources of released volatiles. The unique conditions of the impact, however, m...

Hundreds of impact craters on Mars contain diverse phyllosilicates, interpreted as excavation products of preexisting subsurface deposits following impact and crater formation. This has been used to argue that the conditions conducive to phyllosilicate synthesis, which require the presence of abundant and long-lasting liquid water, were only met early in the history of the planet, during the No...

Introduction: Recent impact craters on the Moon, Mercury, and icy Galilean satellites have produced bright rays extending hundreds or thousands of kilometers from the crater rims. A large rayed crater has never previously been seen on Mars, and it has been assumed that the active aeolian environment would quickly remove the ephemeral ray material [1]. Here we report the discovery of a 10-km dia...

The recent (14 July 2015) flyby of NASA’s New Horizons spacecraft of the dwarf planet Pluto resulted in the first high-resolution images of the geological surfacefeatures of Pluto. Since previous studies showed that the impact crater size-frequency distribution (SFD) of different celestial objects of our solar system follows power-laws, the aim of the present analysis was to determine, for the ...

Introduction: There is a growing interest in the thermal evolution and fluid behavior of impact structures in the context of their possible influence on emergence of life both in the Early Earth and on other Planetary Bodies. This is largely related to hydrothermal mechanisms at work during the cooling of the hot materials produced and deposited in impact craters. Yet most of the research in th...

A new experimental technique to measure crater growth is presented whereby a high speed video captures profiles of a crater forming after impact obtained using a vertical laser sheet centered on the impact point. Unlike previous so called “quarter-space experiments”, where projectiles were launched along a transparent Plexiglas sheet so that growth of half a crater could be viewed, the use of t...

Introduction: The recent missions to Mars with diverse instruments have provided a new perspective for the study of Martian surface landforms. They have permitted the characterization of over 40,000 impact craters ≥ 5 km in diameter [1], showing a diverse cratering record with some quite unusual morphologies. Changes in crater morphology are thought to reflect the impact energy and target prope...

Introduction: The middle-sized icy satellites of Saturn occupy an important niche in solar system studies. This is true also in our understanding of impact crater formation, where the low to moderate surface gravity (g ~ 8-to-30 g/cm3) of these satellites gives us the opportunity to study the role of surface gravity in crater modification on ice-rich targets (in much the same way that study of ...