My primary interests lie in the field of exoplanet science, where I hope to assist in the pursuit to find
potentially habitable planets. My current work is focused on analysis tools for future direct
imaging observations and characterizing planets in reflected light. I am particularly interested
in how an exoplanet's photometry and atmospheric composition can assist in "deconfusing" directly
imaged multi-planet systems and inform our interpretation of reflected light observations of exoplanets.
You can find more about my research here.
When I'm not thinking about planets, I can be found hiking, playing piano, reading, and spending time with my two cats.
I also love to cook and especially enjoy learning about the science behind cooking!
My Background
I began my Ph.D. in the Fall of 2020. Before joining the Planetary Science program
at MIT, I pursued my undergraduate degree at Southeast Missouri State
University. I graduated with my Bachelor's degree in Physics in 2019.
During my last year at Southeast Missouri State, I worked on an
undergraduate research project with my research advisor, Dr. Michael
Cobb. We used ROCKE-3D , a 3-D general circulation model (GCM), to model
the atmosphere of an Earth-like planet in Mars' orbit and investigate
possible habitable conditions.
During my third year at Southeast, I also supported the
Continental-America Telescopic Eclipse (CATE) Experiment as a team member for Site 40, led by Dr. Margaret "Peggy" Hill.
This experiment gathered teams of scientists and citizen scientists across the United States,
with the goal of capturing a time sequence of observations of the solar corona during the
August 21, 2017 solar eclipse. I assisted Site 40 in data collection on the day of the
eclipse and promoted public outreach leading up to the event.
Site 40 Citizen CATE Student Team and the solar eclipse.
Research
During my PhD, I have worked on several different research projects.
My main interests lie in reflected light direct imaging of exoplanets, but I have
also worked on recovering serendpitous detections of Solar system small bodies
and validating observations from an Earth-observing weather-monitoring CubeSat mission.
Below you will find summaries of projects.
Observations of Uranus and Neptune at High Phase Angle from the New Horizons Mission
Ice giant sized exoplanets are among some of the most common planets to exist around other stars. In
order to better understand ice giant sized exoplanets, we can look to our Solar System ice giants
to provide "ground truth" observations and a baseline from which to interpret out data and test
our atmospheric models. As part of its second extended mission, the New Horizons spacecraft observed Uranus
and Neptune at high phase angles using its MVIC instrument. These observations offer an improvement over
previous Voyager observations, which were limited in wavelength range and signal-to-noise ratio.
With the New Horizons data, we aim to perform a phase curve and color analysis of each of the ice
giants, to better understand their atmospheres, energy balance, and scattering properties as analogs
for exoplanet studies.
New Horizons MVIC scans of Uranus from September of 2023 in four
filters. Each panel is centered on the detections of Uranus.
Initial results from the Uranus observations are presented here.
Using Exoplanet Photometry to Support Deconfusion of Directly Imaged Multi-Planet
Systems
To enable characterization of close-in planets orbiting Sun-like stars for
future direct imaging missions, we must first know which detection
corresponds to which planet over the course of multiple observations.
Multi-planet systems around Sun-like stars will experience a "confusion"
problem for future direct imaging surveys searching for habitable planets, due to the number
of planets visible per system, their shorter orbital periods, and their atmospheric characteristics. This
confusion problem makes it difficult to match detections to the correct planet.
The confusion problem. Simulated detections of a 2-planet system over a
period of 1.2 years, which result in two potential orbit combinations for the system (i.e., confusion). (Pogorelyuk
et al. 2022)
My colleagues in STAR Lab developed an algorithm to address this
confusion problem by performing fast orbit fitting and predicting confusion rates for directly imaged systems. This algorithm,
called the "deconfuser", uses astrometric (positional) information for planet detections and generates all possible combinations
of orbit matches for a planetary system.
My research aims to combine photometric information from an exoplanet observation, with the astrometric information that
the deconfuser already considers, to decrease the probability of confusion for a system. I developed a photometry model
to couple with the deconfuser, which calculates the expected brightness for a planet at any given time of detection. I then
implemented an additional ranking metric in the deconfuser to leverage this photometric information to rank orbit combinations
higher if they have more statistically likely orbital phase or brightness results. Preliminary analyses suggest
that the additional photometric information assists in decreasing a system's probability of confusion.
Planetary orbital phases (Credit: ESA)
Searching for Solar System Small Bodies
Solar System small bodies such as asteroids and comets provide a foundation for studying the Solar System.
Studying these bodies poses a technical challenge for observers, due to their small
size and distance from Earth causing them to be very faint on the sky. The synthetic tracking
technique was developed to overcome this observational challenge and identify moving
bodies in an image. My work in this area focused on finding Solar System
small bodies in data collected by the
SPECULOOS and
ASTEP surveys.
I developed and implemented a pipeline, referred to as the LUNA (Looking for
UNknown Asteroids) pipeline. The LUNA pipeline calibrates images, passes them into a publicly-available
synthetic tracker (Tycho Tracker ), and returns follow-up
parameters for each night of observations. On SPECULOOS data, the pipeline can run every day on the previous
night of observations, which allows for timely follow-up if any moving bodies are detected in the field of view.
The pipeline was then adapted to mine archival data from the Antarctic Search for Transiting ExoPlanets (ASTEP)
project.
Stacked images showing a detection of the known Main-Belt Asteroid 2002 NE23 using the LUNA Pipeline.
Additional Work: Earth Weather and Climate, NASA TROPICS Mission
The NASA TROPICS (Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation
of Smallsats) Mission is a mission designed to provide rapid-refresh microwave measurements of the Earth's
troposphere with a constellation of small satellites. The mission will provide nearly all-weather observations
of the temperatre structure, cloud ice, and precipitation horizontal structure of the Earth's atmosphere over the tropics.
The goal of the mission is to provide observations of the atmosphere at high temporal resolution to monitor the rapidly-evolving
features of tropical cyclones.
The TROPICS Pathfinder space vehicle was launched in June 30, 2021 into a sun-synchronous orbit, as a precursor to the full
TROPICS mission. During my time at MIT, I supported the calibration and validation process of the
on-orbit data collected by Pathfinder. I worked on a team in STAR Lab to develop a validation process using a known quality data source
(ERA5 ), a radiative transfer model
(CRTM ), and cloud maps
(GOES-16 & -17 )
to determine the accuracy of Pathfinder's observations. Our method can also be applied to the full satellite
constellation. For more about the TROPICS mission, see
here .
TROPICS Space Vehicle (Credit: MIT LL).
Publications
Major Contributions
Hasler, S. N.*, Pogorelyuk, L., et al. (in prep) The Influence of Photometry on Deconfusion of Directly Imaged Multi-Planet Systems.
Gagnon, A. and Hasler, S. N.*, et al. (in review). Data Validation of the NASA TROPICS Pathfinder Microwave Radiometer.
Hasler, S. N.*, Mayorga, L. C., et al. (accepted) Observations of Uranus at High Phase Angle as seen by New Horizons. Planetary Science Journal. arXiv:2411.04167
Hasler, S. N.*, Burdanov, A. Y., de Wit, J., Dransfield, G., et al. (2023). Small body harvest with the Antarctic Search for Transiting ExoPlanets (ASTEP) project. Monthly Notices of the Royal Astronomical Society, Volume 526, Issue 3, December 2023, Pages 3601–3609, https://doi.org/10.1093/mnras/stad2943.
Burdanov, A. Y., Hasler, S. N., de Wit, J. (2023). GPU-based framework for detecting small Solar System bodies in targeted exoplanet surveys. Monthly Notices of the Royal Astronomical Society, Volume 521, Issue 3, May 2023, Pages 4568–4578, https://doi.org/10.1093/mnras/stad808.
Gagnon, A., Hasler, S., Chew, J., Blackwell, W., Leslie, V., & Cahoy, K. (2022). Data Validation of the NASA Time-Resolved Observations of Precipitation Structure and Storm Intensity with a Constellation of Smallsats (TROPICS) Pathfinder Microwave Radiometer. Proceedings of the Small Satellite Conference, Weekend Session 2: Recent Launches - Research & Academia, SSC22-WKII-01, https://digitalcommons.usu.edu/smallsat/2022/all2022/51/.
*First author publications
Minor Contributions
Burdanov, A. Y., de Wit, J., Brož, M., ..., Hasler, S. N., et al. (accepted) Detections of decameter main-belt asteroids and in-situ characterization of meteorite source regions with JWST, Nat Astron.
Savransky, D., Bailey, V. P., Wolff, S. G., Millar-Blanchaer, M. A., ..., Hasler, S. N., et al. (2024). The Nancy Grace Roman Space Telescope coronagraph community participation program. Proc. SPIE 13092, Space Telescopes and Instrumentation 2024: Optical, Infrared, and Millimeter Wave, 130921I.
Gillon, M., Pedersen, P. P., Rackham, B. V., Dransfield, G., Ducrot, E., ..., Hasler, S., et al. (2024) Detection of an Earth-sized Exoplanet Orbiting the Nearby Ultraool Dwarf Star SPECULOOS-3. Nat Astron., vol. 8, 865–878.
Grundy, W. M., Wenkert, D. D., Simon, A. A., ..., Hasler, S. N., et al. (2024) Recent New Horizons Ralph/MVIC High-Phase Time-Domain Observations of Uranus and Neptune. 55th Lunar and Planetary Science Conference, vol. 3040, Art. no. 2432.
Blackwell, W. J., Crompton, D., Cunningham, A., ..., Hasler, S., et al. (2022). The NASA Time-Resolved Observations of Precipitation Structure and Storm Intensity with a Constellation of Smallsats (TROPICS) Mission: Results from the Pathfinder Demonstration and Look Ahead to the Constellation Mission. Proceedings of the Small Satellite Conference, Weekday Session 5: Next on the Pad, SSC22-V-02, https://digitalcommons.usu.edu/smallsat/2022/all2022/162/.
Penn, M. J., Baer, R., Walter, D., Pierce, M., Gelderman, R., …, Hasler, S., et. al. (2019). Acceleration of Coronal Mass Ejection Plasma in the Low Corona as Measured by the Citizen CATE Experiment. PASP, 132, 014201.
High Phase Angle Observations of Uranus and the Implications for Exoplanet Direct Imaging New Horizons Science Spotlight Seminar
October 2024, Online talk
New Horions Ralph/MVIC Observations of Uranus at High Phase Angles Hasler, S., Mayorga, L. C., Grundy, W, Simon, A., Benecchi, S., et al. 56th Annual Meeting of the Division for Planetary Sciences
October 2024, Boise, Idaho, United States
Observations of Uranus at High Phase Angles as Seen by New Horizons Hasler, S., Mayorga, L. C., Grundy, W, Simon, A., Benecchi, S., et al. New Horizons Science Team Meeting #57
October 2024, Online talk
Addressing Challenges for Reflected Light Direct Imaging: Photometric Variation and Multiplanet System Confusion UCSC Planetary Lunch Seminar
April 2024, Santa Cruz, California, United States
Reducing Detection Confusion in Directly Imaged Multi-Planet Systems Hasler, S., Pogorelyuk, L., Fitzgerald, R., Vlahakis, S., Cahoy, K., Morgan, R. 242nd Meeting of the American Astronomical Society
Yield Modeling Tools Workshop
June 2023, Albuquerque, New Mexico, United States
Reducing Detection Confusion in Directly Imaged Multi-Planet Systems Hasler, S., Pogorelyuk, L., Fitzgerald, R., Vlahakis, S., Cahoy, K., Morgan, R. EMAC Workshop
February 2023, Online talk
Leveraging Photometry for Deconfusion of Directly Imaged Multi-Planet Systems Hasler, S., Pogorelyuk, L., Fitzgerald, R., Vlahakis, S., Cahoy, K., Morgan, R. 241st Meeting of the American Astronomical Society
January 2023, Seattle, Washington, United States [ADS]
The Role of Exoplanet Photometry in Orbit-Fitting of Directly Imaged Multi-Planet Systems Hasler, S., Pogorelyuk, L., Fitzgerald, R., Vlahakis, S., Cahoy, K., Morgan, R. Emerging Researchers in Exoplanet Science Symposium VII
August 2022, State College, Pennsylvia, United States
The Role of Exoplanet Photometry in Orbit-Fitting of Directly Imaged Multi-Planet Systems Hasler, S., Pogorelyuk, L., Fitzgerald, R., Vlahakis, S., Cahoy, K., Morgan, R. 240th Meeting of the American Astronomical Society
June 2022, Pasadena, California, United States [ADS]
The Influence of Photometry on Deconfusion of Directly Imaged Multi-Planet Systems Hasler, S., Pogorelyuk, L., et al. Exoplanets 5
June 2024, Leiden, Netherlands
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