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Addison T. Dove

Publications and source records attributed to Addison T. Dove.

2 recordsLinked to original sources

Morphometric properties of the CP-21 landing site on the Moon at Mons Gruithuisen Gamma

Characterizing terrain surface properties is an essential step in assessing the feasibility of landing successfully at a location on a planetary surface. Slopes and terrain ruggedness index (TRI) values derived from high-resolution (2 m pixel −1 ) digital terrain models provided important constraints in selecting the landing site for the upcoming Payloads and Research Investigations on the Surface of the Moon program as part of the Commercial Lunar Payload Services task order CP-21 mission. The selected landing site needed to balance safety requirements with the ability to achieve the science and exploration goals of the Lunar Vulkan Imaging and Spectroscopy Explorer payload. In this study, we compare several morphometric parameters in the context of the CP-21 landing site on Mons Gruithuisen Gamma, or the Gamma dome, and quantify the information they convey about lunar surface properties to assess their utility for future landing site evaluation. TRI was found to be a useful metric for assessing landing site safety. Metrics that better decouple slope and surface roughness, the vector ruggedness measure and the standard deviation of slope, provided additional information about surface characteristics and textures such as the degree to which roughness is isotropic.

Planetary Science Journal

Survival and growth of larval Pallid Sturgeon are improved by a live diet

Objective Conservation propagation facilities in the upper basin of the Missouri River are currently experiencing inconsistent survival of first-feeding larval Pallid Sturgeon Scaphirhynchus albus among genetic families (i.e., distinct male–female pairings). The inconsistent survival can have unintended negative consequences for genetic representation of Pallid Sturgeon that are returned to the Missouri and Yellowstone rivers. We conducted a laboratory study designed to determine whether a live diet improves survival and growth of first-feeding larval Pallid Sturgeon. Methods First-feeding larval Pallid Sturgeon from three distinct genetic families were assigned to one of the following diets: live first instar brine shrimp ( Artemia franciscana ) nauplii, an Otohime dry diet, a 50–50% combination of Otohime and live first instar brine shrimp nauplii, or food restricted (no food). Mortality was evaluated at the end of each day and at the end of the trial (21 days after the onset of exogenous feeding), and individual weight (g) was measured at the end of the trial. Result Pallid Sturgeon larvae that received a live diet (either solely live first instar brine shrimp nauplii or the combined diet) experienced higher survival than larvae that were fed solely Otohime. Furthermore, there was statistical evidence that larvae receiving solely live first instar brine shrimp nauplii were heavier at 21 days postexogenous feeding than larvae that were fed either solely Otohime or the combined diet. Conclusion Our results suggest that a live diet can improve survival and growth of first-feeding larval Pallid Sturgeon at conservation propagation facilities.

North American Journal of Aquaculture