Catherine Neish

• Western University

Energy and nutrient sources for life could be delivered to Titan’s subsurface water ocean from both its surface above and its core below. Organic matter forming de novo in Titan’s atmosphere and depositing on the surface may hydrolyze upon descent into the ocean with impact-generated melt pools sinking through the ice, adding to a primordial invent...

Titan is the only icy satellite in the solar system with a dense atmosphere. This atmosphere is composed primarily of nitrogen with a few percent methane, which supports an active, methane-based hydrological cycle on Titan. The presence of methane, however, is intriguing, as its lifetime is likely much shorter than the age of the solar system due t...

Young (<1 Ga) craters on the Moon are known to host diverse mixtures of ejecta with varying spectral and physical properties. In this work, we examine 13 yr of bolometric surface temperature data from the Diviner Lunar Radiometer on board the Lunar Reconnaissance Orbiter over the ejecta blankets of 10 lunar craters of varying sizes ( D = 5–43 km) a...

Planetary analog mission simulations are essential for testing science operations strategies and technologies. They also teach us how to use terrestrial analogs to inform studies of extraterrestrial environments. Unoccupied aircraft systems (UASs) have great potential for planetary surface exploration as demonstrated by the Mars 2020 Ingenuity heli...

One of the youngest features on the Moon is Tycho, an 85 km diameter impact crater with a vast ray system that spans much of the lunar nearside. As such, it serves as an important stratigraphic marker for the Moon. One of Tycho’s longest rays crosses the South Pole, where it intersects several candidate landing sites for NASA’s Artemis III mission,...

Titan is an ocean world with a dense atmosphere, where photochemistry produces complex organic molecules that fall to the surface. An important astrobiological question is whether this material can mix with water and form molecules of biological interest. Large impacts heat the moon's subsurface and create liquid water melt pools. A recent study in...

Titan has an organic-rich atmosphere and surface with a subsurface liquid water ocean that may represent a habitable environment. In this work, we determined the amount of organic material that can be delivered from Titan's surface to its ocean through impact cratering. We assumed that Titan's craters produce impact melt deposits composed of liquid...

The Miniature Radio Frequency instrument (Mini-RF) on the Lunar Reconnaissance Orbiter obtained widespread synthetic aperture radar observations of the Moon in the S band (12.6 cm), including nearly complete coverage at both lunar poles. The currently archived monostatic data have spatial offsets from the lunar reference frame, making them more dif...

Planetary radar observations have provided invaluable information on the solar system through both ground-based and space-based observations. In this overview article, we summarize how radar observations have contributed in planetary science, how the radar technology as a remote-sensing method for planetary exploration and the methods to interpret...

New Horizons showed that Pluto exhibits a wide range of geologic groups, with much of the surface modified by volatile ice processes. Impact craters are a valuable tool to investigate how these regions have evolved, as they record the effects of various modification mechanisms and retain information on the properties of the bedrock ice(s). In this...

Selk crater is an ∼80 km diameter impact crater on the Saturnian icy satellite Titan. Melt pools associated with impact craters like Selk provide environments where liquid water and organics can mix and produce biomolecules like amino acids. It is partly for this reason that the Selk region has been selected as the area that NASA’s Dragonfly missio...

Selk crater is an $\sim$ 80 km diameter impact crater on the Saturnian icy satellite, Titan. Melt pools associated with impact craters like Selk provide environments where liquid water and organics can mix and produce biomolecules like amino acids. It is partly for this reason that the Selk region has been selected as the area that NASA's Dragonfly...

Titan is a chemically rich world that provides a natural laboratory for the study of the origin of life. Titan’s atmospherically derived C x H y N z molecules have been shown to form amino acids when mixed with liquid water, but the transition from prebiotic chemistry to the origin of life is not well understood. Investigating this prebiotic enviro...

As the only icy satellite with a thick atmosphere and liquids on its surface, Titan represents a unique end-member to study the impact cratering process. Unlike craters on other Saturnian satellites, Titan’s craters are preferentially located in high-elevation regions near the equator. This led to the hypothesis that the presence of liquid methane...

As the only icy satellite with a thick atmosphere and liquids on its surface, Titan represents a unique end-member to study the impact cratering process. Unlike craters on other Saturnian satellites, Titan's craters are preferentially located in high-elevation regions near the equator. This led to the hypothesis that the presence of liquid methane...

NASA’s Dragonfly mission will send a rotorcraft lander to the surface of Titan in the mid-2030s. Dragonfly's science themes include investigation of Titan’s prebiotic chemistry, habitability, and potential chemical biosignatures from both water-based “life as we know it” (as might occur in the interior mantle ocean, potential cryovolcanic flows, an...

Hypervelocity impacts on terrestrial bodies have the potential to rapidly heat and redistribute silicate target material to form impact melt flows. On the Moon, a subset of impact melt deposits exited the craters as laterally moving flows that moved away from the crater rim under the influence of gravity. These impact melt flows exhibit similaritie...

High‐resolution images and elevation data sets from the Lunar Reconnaissance Orbiter along with spectral data from the Clementine mission are used to identify and map in detail the well‐preserved Late Imbrian Tsiolkovskiy crater situated on the far side of the Moon. This study identifies five distinct morphologic units associated with Tsiolkovskiy...

As one of two planetary objects (other than Earth) that have solid surfaces, thick atmospheres, and astrobiological significance, Titan, like Mars, merits ongoing study with multiple spacecraft. We propose that a Titan orbiter dedicated to geophysics, geology, and atmospheric science be added to the New Frontiers menu for the coming decade.

As one of two planetary objects (other than Earth) that have solid surfaces,thick atmospheres, and astrobiological significance, Titan, like Mars, merits ongoing studywith multiple spacecraft. We propose that a Titan orbiter dedicated to geophysics, geology,and atmospheric science be added to the New Frontiers menu for the coming decade.

This study presents a modified semi-empirical radar scattering model for weathered rough rock surfaces. Weathered rocks generally have dry surfaces except for a few hours after heavy rain due to their rapid drainage compared to bare soils. We find that the dielectric properties of the rocks themselves and the moisture content of a marginal amount o...

We used radar and LiDAR remote sensing data to understand the roughness, morphology and emplacement processes of the 2014‒2015 Holuhraun lava flow field in Iceland, as an analogue for lunar and Martian lava flows. Remote sensing observations alone can provide general distinctions between smooth and rough lava flows. However, more information is req...

This study investigates the polarimetric radar signatures of geological units in the Canadian Arctic to characterize their physical surface properties. It focuses on the Tunnunik and Haughton meteorite impact structures using RADARSAT-2 quad polarimetric synthetic aperture radar (SAR) data. The geological units show different three-dimensional (3-D...

In the version of this Article originally published, the author Rosaly Lopes was mistakenly affiliated with Northern Arizona University. Her affiliation has now been corrected to: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA.

Remote sensing has revolutionized resource exploration by enabling quick surveillance of large areas. Quad-polarimetric synthetic aperture radar (SAR) is useful for assessing surface roughness, but few studies have applied it for geological mapping. Located in the Canadian Arctic, Axel Heiberg Island is a suitable site for exploring remote predicti...

We examine the variations in CPR that are a function of incidence angle and include them with analysis of variations in CPR as a function of bistatic angle for several terrain types, using data obtained from Mini-RF monostatic and bistatic observations.

Here we describe a methodology that provides more accurate geospatial information for Mini-RF bistatic radar images.

Energy released during impact cratering events can rapidly heat silicate materials to superliquidus temperatures. This can generate gravity-driven melt flows that appear to behave like lava flows. The rheology of impact melts on the Moon and other planetary bodies is poorly constrained. To address this, we characterized three lunar simulant materia...

We present a geomorphologic map of Titan's polar terrains. The map was generated from a combination of Cassini Synthetic Aperture Radar (SAR) and Imaging Science Subsystem imaging products, as well as altimetry, SARTopo and radargrammetry topographic datasets. In combining imagery with topographic data, our geomorphologic map reveals a stratigraphi...

Comparing the present states of the terrestrial planets can lead to new insights into the evolution of habitable regions in our own and other solar systems. As the terrestrial planet closest in size to Earth, Venus is a particularly interesting analogue when considering the future of our own world. Exploration of Venus, however, presents many chall...

Comparing the present states of the terrestrial planets can lead to new insights into the evolution of habitable regions in our own and other solar systems. As the terrestrial planet closest in size to Earth, Venus is a particularly interesting analogue when considering the future of our own world. Exploration of Venus, however, presents many chall...