K. M. Stack
A5079710286- Planetary Science and Exploration
- Astro and Planetary Science
- Space Exploration and Technology
- Geology and Paleoclimatology Research
- Space Science and Extraterrestrial Life
- Paleontology and Stratigraphy of Fossils
- Marine and environmental studies
- Geochemistry and Geologic Mapping
- Geological formations and processes
- Hydrocarbon exploration and reservoir analysis
- Spaceflight effects on biology
- Methane Hydrates and Related Phenomena
- Geological Studies and Exploration
- Maritime and Coastal Archaeology
- Geological and Geochemical Analysis
- Aeolian processes and effects
- Space Satellite Systems and Control
- Geological Modeling and Analysis
- Space exploration and regulation
- Ancient and Medieval Archaeology Studies
- Isotope Analysis in Ecology
- Geological and Geophysical Studies
- Coastal and Marine Dynamics
- Ancient Mediterranean Archaeology and History
- Congenital Heart Disease Studies
Jet Propulsion Laboratory
2016-2025
Williams College
2025
Boston Children's Hospital
2024
Children's Hospital of Philadelphia
2022-2024
Minneapolis VA Health Care System
2024
Georgetown University Medical Center
2024
Georgetown University
2024
Boston Children's Museum
2024
University of Pennsylvania
2024
William W Backus Hospital
2022
The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of environment that would have been suited support a martian biosphere founded on chemolithoautotrophy. This aqueous was characterized by neutral pH, low salinity, variable redox states both iron sulfur species. Carbon, hydrogen, oxygen, sulfur, nitrogen, phosphorus were measured directly as key biogenic elements; inference, is assumed available. probably had...
Sedimentary rocks at Yellowknife Bay (Gale crater) on Mars include mudstone sampled by the Curiosity rover. The samples, John Klein and Cumberland, contain detrital basaltic minerals, calcium sulfates, iron oxide or hydroxides, sulfides, amorphous material, trioctahedral smectites. smectite has basal spacing of ~10 angstroms, indicating little interlayer hydration. Cumberland both ~13.2 angstroms. larger suggests a partially chloritized magnesium facilitating H2O retention. Basaltic minerals...
Ancient lake system at Gale crater Since 2012, the Curiosity rover has been diligently studying rocky outcrops on Mars, looking for clues about past water, climate, and habitability. Grotzinger et al. describe analysis of a huge section sedimentary rocks near crater, where Mount Sharp now stands (see Perspective by Chan). The features within these sediments are reminiscent delta, stream, deposits Earth. Although individual lakes were probably transient, it is likely that there was enough...
Observations by the Mars Science Laboratory Mast Camera (Mastcam) in Gale crater reveal isolated outcrops of cemented pebbles (2 to 40 millimeters diameter) and sand grains with textures typical fluvial sedimentary conglomerates. Rounded conglomerates indicate substantial abrasion. ChemCam emission spectra at one outcrop show a predominantly feldspathic composition, consistent minimal aqueous alteration sediments. Sediment was mobilized ancient water flows that likely exceeded threshold...
Sedimentary rocks examined by the Curiosity rover at Yellowknife Bay, Mars, were derived from sources that evolved an approximately average martian crustal composition to one influenced alkaline basalts. No evidence of chemical weathering is preserved, indicating arid, possibly cold, paleoclimates and rapid erosion deposition. The absence predicted geochemical variations indicates magnetite phyllosilicates formed diagenesis under low-temperature, circumneutral pH, rock-dominated aqueous...
Abstract The Curiosity rover has analyzed abundant light‐toned fracture‐fill material within the Yellowknife Bay sedimentary deposits. ChemCam instrument, coupled with Mastcam and ChemCam/Remote Micro Imager images, was able to demonstrate that these fracture fills consist of calcium sulfate veins, many which appear be hydrated at a level expected for gypsum bassanite. Anhydrite is locally present found in location characterized by nodular texture. An intricate assemblage veins crosses...
Perseverance images of a delta on Mars The rover landed in Jezero crater, Mars, February 2021. Earlier orbital showed that the crater contains an ancient river was deposited by water flowing into lake billions years ago. Mangold et al . analyzed taken shortly after landing show distant cliff faces at edge delta. exposed stratigraphy and sizes boulders allowed them to determine past level discharge rates. An initially steady flow transitioned intermittent floods as planet dried out. This...
The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below crater's sedimentary delta, finding that floor consists igneous rocks altered by water. lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at base magma body. Magnesium-iron carbonates along grain boundaries indicate reactions with carbon dioxide-rich water under water-poor conditions....
The Perseverance rover landed in Jezero crater, Mars, February 2021. We used the Scanning Habitable Environments with Raman and Luminescence for Organics Chemicals (SHERLOC) instrument to perform deep-ultraviolet fluorescence spectroscopy of three rocks within crater. identify evidence two distinct ancient aqueous environments at different times. Reactions liquid water formed carbonates an olivine-rich igneous rock. A sulfate-perchlorate mixture is present rocks, which probably by later...
Before Perseverance, Jezero crater's floor was variably hypothesized to have a lacustrine, lava, volcanic airfall, or aeolian origin. SuperCam observations in the first 286 Mars days on revealed and intrusive terrain with compositional density stratification. The dominant lithology along traverse is basaltic, plagioclase enrichment stratigraphically higher locations. Stratigraphically lower, layered rocks are richer normative pyroxene. lowest observed unit has highest inferred olivine-rich...
The geological units on the floor of Jezero crater, Mars, are part a wider regional stratigraphy olivine-rich rocks, which extends well beyond crater. We investigated petrology olivine and carbonate-bearing rocks Séítah formation in Jezero. Using multispectral images x-ray fluorescence data, acquired by Perseverance rover, we performed petrographic analysis Bastide Brac outcrops within this unit. found that these composed igneous rock, moderately altered aqueous fluid. mainly made...
Abstract The presence and distribution of preserved organic matter on the surface Mars can provide key information about Martian carbon cycle potential planet to host life throughout its history. Several types molecules have been previously detected in meteorites 1 at Gale crater, 2–4 . Evaluating diversity detectability elsewhere is important for understanding extent processes availability sources 1,5,6 Here we report detection Raman fluorescence spectra consistent with several species...
Abstract The first samples collected by the Mars 2020 mission represent units exposed on Jezero Crater floor, from potentially oldest Séítah formation outcrops to youngest rocks of heavily cratered Máaz formation. Surface investigations reveal landscape‐to‐microscopic textural, mineralogical, and geochemical evidence for igneous lithologies, some possibly emplaced as lava flows. contain major rock‐forming minerals such pyroxene, olivine, feldspar, accessory including oxides phosphates,...
Abstract Sedimentary fans are key targets of exploration on Mars because they record the history surface aqueous activity and habitability. The sedimentary fan extending from Neretva Vallis breach Jezero crater's western rim is one 2020 Perseverance rover's main targets. spent ∼250 sols exploring collecting seven rock cores lower ∼25 m exposed within fan's eastern scarp, a sequence informally named “Shenandoah” formation. This study describes sedimentology stratigraphy Shenandoah formation...
The NASA Mars 2020 Perseverance Rover Mission has collected samples of rock, regolith, and atmosphere within the Noachian-aged Jezero Crater, once site a delta-lake system with high potential for habitability biosignature preservation. Between sols 109 1,088 mission, 27 sample tubes have been sealed, including witness tubes. Each sealed tube along detailed documentation provided by instrument payload, preserving geological environmental context. Samples representative stratigraphy each four...
Abstract The first four rocks examined by the Mars Science Laboratory Alpha Particle X‐ray Spectrometer indicate that Curiosity landed in a lithologically diverse region of Mars. These rocks, collectively dubbed Bradbury assemblage, were studied along an eastward traverse (sols 46–102). Compositions range from Na‐ and Al‐rich mugearite Jake_Matijevic to Fe‐, Mg‐, Zn‐rich alkali‐rich basalt/hawaiite Bathurst_Inlet span nearly entire FeO* MnO data sets previous Martian missions meteorites....
Research Article| October 01, 2013 A hematite-bearing layer in Gale Crater, Mars: Mapping and implications for past aqueous conditions A.A. Fraeman; Fraeman 1Department of Earth Planetary Sciences, Washington University St. Louis, Missouri 63130, USA Search other works by this author on: GSW Google Scholar R.E. Arvidson; Arvidson J.G. Catalano; Catalano J.P. Grotzinger; Grotzinger 2Department Geological California Institute Technology, Pasadena, 91125, R.V. Morris; Morris 3NASA Johnson Space...
Abstract What allows a planet to be both within potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy ongoing discovery terrestrial‐type planets around other stars, our own solar system becomes key testing ground for ideas about what factors control planetary evolution. Mars provides system's longest record interplay physical chemical processes relevant on an accessible rocky with atmosphere hydrosphere. Here we review current...
Abstract Recent robotic missions to Mars have offered new insights into the extent, diversity and habitability of Martian sedimentary rock record. Since Curiosity rover landed in Gale crater August 2012, Science Laboratory Team has explored origins ancient fluvial, deltaic, lacustrine aeolian deposits preserved within crater. This study describes sedimentology a ca 13 m thick succession named Pahrump Hills member Murray formation, first fine‐grained deposit discovered situ on Mars. work...
Abstract For ~500 Martian solar days (sols), the Mars Science Laboratory team explored Vera Rubin ridge (VRR), a topographic feature on northwest slope of Aeolis Mons. Here we review sedimentary facies and stratigraphy observed during sols 1,800–2,300, covering more than 100 m stratigraphic thickness. Curiosity's traverse includes two transects across ridge, which enables investigation lateral variability over distance ~300 m. Three informally named members Murray formation are described:...
The Sheepbed member of the Yellowknife Bay formation in Gale crater contains millimeter-scale nodules that represent an array morphologies unlike those previously observed sedimentary deposits on Mars.Three types have been identified order decreasing abundance: solid nodules, hollow and filled a variant whose voids with sulfate minerals.This study uses Mast Camera (Mastcam) Mars Hand Lens Imager (MAHLI) images from Science Laboratory Curiosity rover to determine size, shape, spatial...
Mars Science Laboratory (MSL) Curiosity rover data are used to describe the morphology of desiccation cracks observed in ancient lacustrine strata at Gale crater, Mars, and interpret their paleoenvironmental setting. The indicate subaerial exposure facies Sutton Island member Murray formation. In association with ripple cross-stratification possible eolian cross-bedding, these a transition from longer-lived perennial lakes recorded by older younger characterized intermittent exposure....