About Us

My name is Lauren Ilsedore Cleeves (Ilse), and I am an Assistant Professor of Astronomy jointly appointed in the Department of Chemistry at the University of Virginia. I am also an Adjunct Assistant Astronomer at the National Radio Astronomy Observatory (NRAO) in Charlottesville, VA. Prior to joining UVa in 2018, I was a NASA Hubble Postdoctoral Fellow in the Radio & Geoastronomy Division of the Center for Astrophysics. 

My work has focused on bringing together and reconciling theoretical models of the chemistry of planet formation with observational constraints from ground and space based observatories. In addition to clues from the astronomical data, our group endeavors to connect all scales by incorporating our knowledge of the primitive solar nebula from the cometary and meteoritic record. 

Deryl Long joined the UVa Astro Graduate program in 2020 and is interested understanding key processes that alter the composition of the planet-forming region of disks - the midplane. Specifically Deryl uses novel observational and modeling techniques to ilucidate the key ionization mechanisms active in the midplane using a combination of spatially resolved data and large disk samples, through the ALMA Disk-Exoplanet C/Onnection (DECO) Large Program.

Website: https://derylong.github.io/

Rachel Gross joined the UVa Chemistry program in Fall 2020 as a UVa Origins Interdisciplinary Doctoral Fellow and is investigating the role of environment, especially external ultraviolet radiation, in setting the chemistry of planet forming disks. In collaboration with Cathy Dukes Lab in the UVA School of Engineering, Dept. of Materials Science, Rachel (co-supervised by Dr. Jeroen Terwisscha van Scheltinga) have recently built an ice experimental set up for exploring photo and particle driven solid-phase chemistry.

Amina Diop joined the Cleeves group in Fall 2021 as a John F. Angle Graduate Fellow. She is presently working on using astrochemical models of protoplanetary disks and machine learning techniques to understand the impact of the interplay between chemical and physical processes on CO chemistry. In the future, she is planning to use a combination of observations, astrochemical models, and machine learning to constrain accurately key disk properties such as disk masses and C/O ratios. She is also part of the ALMA DECO team. Amina was awarded a NASA FINESST Fellowship and a SigHPC Fellowship in 2024. 

Amanda Alvarado joined the UVa Chemistry department in Fall 2022 as a Bridge to the Doctorate Fellow. She has a Master’s degree in Chemistry from the University of Puerto Rico, where she had previously carried out research on the spectroscopy and mapping of water lines in star formation regions. Currently at the Cleeves group, she is modeling the structure of protoplanetary disks in order to explore the relationship between disk morphology and its spectra, especially for the hydrogen deuteride molecule. Amanda is carrying out the modeling necessary for the ASTHROS and POEMM NASA missions. 

Dr. Nick Ballering arrived to UVa as a VICO Postdoctoral Fellow in 2019. Nick is an expert on understanding the architectures and compositions of debris disks using a wide range of wavelength from Hubble Space Telescope to ALMA. He also works on younger disks still in the gas-rich phase via a survey of the young stars in Orion with ALMA with an eye toward understanding them as population. Now he is applying his expertise on solid state opacities to make observational predictions for ice composition(s) of disks with the upcoming James Webb Space Telescope.

Website: https://www.nickballering.com/

Dr. Jamila Pegues is a STScI Postdoctoral Fellow at the Space Telescope Science Institute in Baltimore. Her background is in Astronomy & Astrophysics (PhD) and Computational Science and Engineering (MS).  As part of her fellowship, she carries out research in collaboration with our group, specifically surveying and modeling photochemistry chemistry in protoplanetary disks.  

Website: https://www.jamilapegues.com/

Dr. Charles Law joined UVa as a NHFP Sagan Fellow in Fall 2023. Charles’ research employs high spatial resolution observations from (sub-)millimeter interferometers, such as the ALMA, SMA, and VLA, to characterize the environments in which young stars and planets are forming in fine detail. He is also interested in using chemical signatures to identify and characterize protoplanets still embedded in their disks.

Website: https://claw-astro.github.io/

Aashish Gupta, currently a PhD student at ESO Germany, will join UVa as a VICO Postdoctoral Fellow in January 2024. He is interested in investigating the interplay between star-forming environments and planet-forming disks. His recent research focuses on systematically studying the late-stage infall of material onto these disks, primarily using ALMA data.

Website: https://aashishgpta.github.io/

Kyle Gresko is a fourth-year undergraduate at UVA studying Astronomy and Physics. He joined the Cleeves Group through as a 2024 VICO Undergraduate summer research student, working with Charles Law using SMA observations to investigate HNC as a potential tracer in protoplanetary disks. He has previously worked studying meteorites as analogues for asteroids in reference to OSIRIS-REx and space weathering with the Laboratory for Astrophysics and Surface Physics under Cathy Dukes. Kyle will graduate from UVA in Spring 2025. 

Astra Vo is a fourth-year undergraduate at UVA studying Astronomy and Physics. She joined the group through the 2024 VICO Undergraduate summer research program. Astra modeled the survivability of ice in the outskirts of planet forming disks when exposed to strong UV fields from nearby stars in a cluster. She found ice was surprisingly resilient due to the high gas densities present in disks, promoting efficient and competitive freeze-out. This work was presented at the UVA VICO-CICO summer research symposium. 

Becky Williams graduated in 2024 from UVa double majoring in astronomy and biology. She began working with the group through the 2022 VICO Undergraduate Summer Research Fellowship Program, searching for weak emission from molecular oxygen in the protoplanetary disk around TW Hya. She is now modeling sulfur chemistry in disks to identify possible major sulfur-carrying species.

Claire Thilenius graduated in 2024 in UVa's astronomy program. She developed tools to make interferometric imaging with clean more transparent, building a tutorial for junior scientists. She is interested in science and science education. 

Thomas Maher graduated from UVA in 2024 in UVa's astronomy program and is now pursuing a doctorate in Philosophy. While at UVA, Thomas worked with Dr. Charles Law on using novel techniques in the visibility plane to search for large scale winds that are below the noise limit in the image. This work is being submitted as a Research Note to AAS Journals. 

Abby Waggoner joined the UVa Chemistry department in Fall 2018 with an NSF GRFP Fellowship. During the 2017 Summer SAO REU program she investigated how bright X-ray flares might produce abundant bursts of water in the surface of protoplanetary disks. She continues this research to investigate how energetic events across the spectrum can influence the chemistry of disks, and by extension forming planets within them. She is also a writer for the science blog Astrobites. Abby will join University of Wisconsin's Department of Astronomy in Fall 2024 as a postdoctoral researcher with Professor Ke Zhang. 

Renato Mazzei joined the group in Fall 2018, co-advised with UVa Professor Zhi-Yun Li. He recently investigated future prospects for constraining magnetic fields in planet-forming disks using the Zeeman Effect with the Atacama Large Millimeter Array. In addition, he is using models to predict the observable polarization properties of magnetic fields threading larger scale molecular clouds, to compare to future BLASTPOL observations. Together, Renato will observationally constrain magnetic fields on all scales relevant for star and planet formation.

Dr. Jeroen Terwisscha van Scheltinga was part of the Cleeves group from January 2022 through March 2023. Jeroen is an expert in laboratory astrochemistry and in observations with the Atacama Large Millimeter Array, in particular in understanding the origins of organic molecules in disks using their ortho/para spins as a diagnostic of formation environment.

Dr. Dana Anderson was part of the group from 2019-2022. She received her PhD from Caltech in the GPS department. Dana is an expert in chemical modeling and radio observations of protoplanetary disks. Lately, she has been interested in the carbon and nitrogen depletion problem seen both in primordial disks as well as in solar system bodies. Dana is now a Carnegie EPL Postdoctoral Fellow in Washington, DC.

Jee-Ho Kim a final year UVa undergraduate double majoring in Astro and Media Studies. She joined the group via the 2020 Summer VICO Research Fellowship Program and continued work into the academic year. Jee-Ho is an expert in searching for asymmetric emission against a bright background with the hopes of finding young embedded protoplanets that are otherwise difficult to see. 

Dr. Ellen Price is a 51 Peg B fellow at U Chicago. Formerly she was a graduate student at Harvard working with Karin Oberg and myself. She modelled how the nature of gas accretion in disks can alter the disk's composition over time by transporting more or less volatile materials into different regions. By taking into account the viscous evolution of the disk and the time evolving properties of the young star, Ellen finds organic molecules can become enhanced in the inner few AU of disks, i.e., the terrestrial planet forming region. More recently, Ellen has investigating the chemical implications of radial pebble drift on ice composition in disks. 

Colette Levens worked with the Cleeves group while an undergraduate at Mary Baldwin University majoring in applied mathematics and minoring in physics. Under the supervision of Dr. Ballering, Colette investigated the dusty disk of the white dwarf system G29-38, which shows a peculiar SED. 

Jackson Baker is a fourth-year undergraduate at UVa double majoring in Astronomy and Environmental Sciences. He joined the Cleeves Group as part of the Undergraduate Thesis program and is carrying out work under the supervision of Ilse Cleeves. He is investigating the current understanding of sulfur molecules in space and their reactions in order to help build a more comprehensive database for sulfur astrochemistry, which presently does not exist.

Richard Seifert joined the UVA astronomy department and the Cleeves group in Fall 2018 coming from UT Austin, where he majored in Astrophysics and Mathematics. While at UT, he looked at the z>2 COSMOS field in 850μm to see how galaxy cluster formation affects the molecular gas content of galaxies, and wrote a python reduction pipeline for the Hydra multi-object spectrograph at Kitt Peak. As part of the Cleeves Group, he modeled the ionization chemistry of the enigmatic IM Lup system with the goal of mapping its disk ionization fraction. With data science training obtained in part at UVa he will be starting a position as a Data Scientist at General Motors, Austin in Spring 2021.

Fatimah Hussein was part of the Cleeves group from 2020-2021 as part of UVa's newly established Bridge to the Doctorate Program. She graduated in Fall 2020 from the University of the Virgin Islands, where she had previously carried out research on implications for C/O ratios with Dr. Christian Eistrup (through the VICO Summer Research Program). At UVa she is exploring how accretion outbursts 'leave their mark' on late phase protoplanetary disk chemistry via computational models. 

Dave Gutierrez worked with the Cleeves Group in Fall 2019. Dave explored the peculiar ammonia to water ratio observed with the Herschel Space Observatory in the TW Hya protoplanetary disk. The ratio observed in this disk was inconsistent with the ratios seen in interstellar clouds and comets. Dave found that the surface chemistry of the disk was likely not an accurate representation of the midplane, which he wrote up as his undergraduate thesis at UVa.

Christopher Pede worked with the Cleeves Group in Fall and Spring 2020. Chris set out to chemically map out the distribution of species like N2H+ and HCN in the TW Hya disk. He investigated whether a smooth scale emission pattern could be consistent with the observations of HCN, and instead found that there may be some underlying symmetric ring-like structure.