Overview

I use samples from the meteorite collection at the American Museum of Natural History to examine the spectral characteristics, mineralogy, petrology, and trace element chemistry of ordinary and carbonaceous chondrites. I use a combination of analytic techniques to answer questions about the chemical and physical evolution in the early solar system, to constrain the relationship between 2D and 3D mineralogy and petrology of meteoritic samples, and the effect of variables such as grain size, temperature, and petrologic type on visible-near-infrared (VNIR) spectra of ordinary chondrites to better characterize remotely sensed asteroids. My broader research interests include: cosmochemistry/meteoritics, protoplanetary disk evolution, planet formation, comparative planetology, planetary spectroscopy, data visualization, and science communication.

My dissertation research spans three broad categories, which I outline below.

Trace Element Chemistry of Chondrites

Red-Green-Blue (RGB) composite element map of a slice of the Renazzo CR chondrite. Red = Mg, Green = Ca, Blue = Al. Common components of carbonaceous chondrites are labeled. Image 12.288 x 4.096 mm.
The origin of the earliest solids in the solar system, preserved for 4.56 billion years in primitive meteorites, is poorly understood, in part because of the lack of detailed chemical data on individual phases within representative populations of these solids. As part of my dissertation, I am completing a large scale survey of trace element abundances in modally dominant mineral phases across the component population of carbonaceous Renazzo-group (CR) and Vigarano-group (CV) chondrites using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Trace elements, and rare earth elements (REEs) in particular, are important because of their ability to reveal precursor characteristics, formation conditions, and processing histories of chondrite constituents. They are especially useful in assessing the origin of chondrules and chondrites because the REE patterns can survive the secondary processing (aqueous alteration, metamorphism, shock) that these rocks endure. Determining the large-scale distribution of trace elements across carbonaceous chondrite groups will provide evidence for either a single or multiple reservoir origin for these chondrites, and result in key constraints for dynamical accretion mechanisms in astrophysical models of the early solar system.

Presented at: 84th Annual Meeting of the Meteoritical Society

Multi-dimensional Analysis of Ordinary Chondrites

Left: 2D slice from 3D CT scan of Soko-Banja (LL4). Resolution = 8.8 microns/voxel. Middle: 3D volume rendered from tiff stack of X-ray maps from the CT scan. Right: Metal inclusions segmented from 3D volume of Soko-Banja.
Mineralogy within ordinary chondrite meteorites is highly variable, dependent on petrologic type, and the result of differing parent body processes. Quantifying representative mineralogy in meteorites often involves destructive techniques, which sacrifice petrographic context in the sample. Additionally, traditional methods such as point counting do not provide a realistic estimation of modal mineralogy in these ordinary chondrite samples due to their fine-grained nature. I have combined the non-destructive methods of 3D computed tomography (CT) with 2D X-ray element intensity mapping (via an electron microprobe) to quantitatively determine mineral modal abundances and variability across petrologic types of ordinary chondrites without losing petrographic context in each sample. This broad survey of the ordinary chondrites has provided a robust and seminal dataset that tracks mineralogy and petrology in 2 and 3 dimensions across all petrologic types of the ordinary chondrites, better characterizing the multi-dimensional effects of increasing degrees of parent body thermal metamorphism. This work is part of a broader effort to utilize precise mineral abundances in meteorites to quantitatively link laboratory spectroscopy of meteorites to spectroscopy of asteroids to better understand parent body and asteroid compositions.

Presented at: LPSC (2021), LPSC (2020), Goldschmidt (2019).

Laboratory Spectroscopy of Meteorites

Spectra of the four size fractions of the Zhovtnevyi (H6) meteorite, measured at 10°C.
Laboratory infrared spectral analysis of well-characterized meteorite samples can be employed to more quantitatively analyze asteroid remote sensing data in conjunction with returned samples. I am examining the combined effects of temperature, particle size, and petrologic type on visible and near-infrared (VNIR) spectra of equilibrated (petrologic types 4-6) samples from each ordinary chondrite meteorite group (H, L, LL). VNIR spectra of the ordinary chondrite material were measured under simulated asteroid surface conditions at a series of temperatures chosen to mimic near-Earth asteroid surfaces. In order to characterize changes in spectral features due to variations in mineralogy, I used X-ray element maps of meteorite thick sections taken with an electron microprobe to calculate the exact bulk mineral abundances for each meteorite, and X-Ray Diffraction (XRD) measurements of each meteorite powder to account for variations in mineralogy due to size fraction. Spectral studies of meteorites combined with detailed petrologic analysis of the samples will greatly enhance interpretation of current and future planetary remote sensing data sets. This work continues an effort to develop a comprehensive spectral library of materials relevant to airless bodies and contemporaneous asteroid missions.

Presented at: 53rd Annual Meeting of the AAS Division for Planetary Sciences (2021)

Research Experience

American Museum of Natural History
Department of Earth and Planetary Sciences
(2016-present)
Graduate Student Researcher
As part of my dissertation, I am characterizing the mineralogy of ordinary chondrite meteorites and trace element chemistry of carbonaceous chondrite meteorites with Denton S. Ebel.

Stony Brook University
Department of Geosciences
(2016-present)
Collaborating Researcher
Measured VNIR reflectance and MIR emissivity spectra of powdered ordinary chondrite meteorite samples as part of a joint AMNH/SBU project with Timothy D. Glotch.

American Museum of Natural History
Department of Earth and Planetary Sciences
(June 2015 - June 2016)
Research Assistant
Contributed to various projects that exposed me to planetary science topics and sample preparation and analysis methods. Learned how to operate an electron microprobe and a LA-ICP-MS.

American Museum of Natural History
Department of Astrophysics
(January 2014 - May 2015)
Research Assistant
Worked on the expansion of a one-dimensional numerical model, part of a larger numerical simulation examining the consequence of current sheet formation in protoplanetary disks.

MDM 2.4m Telescope
Kitt Peak, Arizona
(January 2014, January 2015)
Observing Assistant
Observed cataclysmic variable stars for 14 nights using the 2.4m telescope at the MDM Observatory on Kitt Peak in Arizona. Data collected was published in Mukadam et. al (2016).

SETI Institute REU Program
NASA Ames
(June 2014 - August 2014)
Research Intern
Validated Kepler planet candidates using speckle imaging from ground-based telescopes under the guidance of Kepler team scientists (Jason Rowe and Steve Howell) at NASA Ames.

Earth Intern Program
Lamont Doherty-Earth Observatory
Research Intern
(June 2013 - August 2013)
Analyzed a peat core from Arctic Siberia using macrofossil identification, LOI, leaf wax n-alkane extraction, and hydrogen isotope analysis to reconstruct the vegetation, climate, and carbon sequestration of the region over time.

Intel Independent Research
Research Grant Recipient
(July 2009 - June 2010)
As a high school junior, I received a $500 Intel Research Grant to develop a research project focusing on the eclipse of the Epsilon Aurigae star system. I observed then proposed a model for the system and presented a final paper at the 2010 Society for Astronomical Sciences Symposium.