2024 EiOB Kentucky

The 2024 iteration of Exoplanets in Our Backyard took place in Louisville, Kentucky, from 13-15 November.

The meeting was centered around four key themes in exoplanetary science (see below), included several invited speakers as well as poster sessions and discussion opportunities (read below for further descriptions on sessions). 

2024 EiOB Scientific Organizing Committee (SOC) Members:

Thomas Fauchez (Co-Chair), Erika Kohler (Co-Chair), Raphael Attié, Elsa Ducrot, Sarah Moran, Stephanie Olson, Eddie Schwieterman

2024 EiOB Local Organizing Committee (LOC) Members:

Timothy Dowling (Chair), Gerard Williger, Benne Holwerda

Workshop Description

The exploration of exoplanets is a vast and complex domain, requiring collective efforts from Solar System Science to Astrophysics to address the larger challenges it presents. Collaboration is the linchpin of addressing large problems in exoplanet research. We will examine successful collaborative efforts, both within and beyond the field, and distill the key ingredients for their success. This workshop will provide a platform for networking and connecting researchers from various backgrounds to foster interdisciplinary partnerships. Astrophysicists, solar physicists, Earth and planetary scientists interested in the intersections between exoplanetology and all other disciplines will find this workshop immensely beneficial. This workshop will foster a collaborative atmosphere (no pun intended) that encourages the sharing of cross-domain knowledge and expertise, ultimately aiding in the accurate detection and characterization of exoplanet atmospheres.

This workshop will heavily focus on discussion, collaboration, and developing cross discipline research. As such, the presenters will be invited speakers chosen to stimulate discussion amongst the workshop attendees.  Abstract submissions are not required and will be assigned a poster. The topics you see below are only “guidelines” topics. Abstracts are not required to strictly correspond to these topics as long as they relate to our general overview. 

Whether you are an experienced researcher or a budding enthusiast, this workshop session promises to inspire, educate, and spark new ideas. Come and be a part of the collective effort to uncover the secrets of these distant worlds and the processes that shape them.

Science Themes

Session 1: Star-Exoplanet Interactions Using Our Heliosphere as a Rosetta Stone

Overview

The study of exoplanets’ habitability do not just revolve around stellar and planetary characteristics taken in isolation. Interactions between the activity of the host star and a planet play a pivotal role in its ability to maintain an atmosphere, its plausible composition, and ultimately, its ability to host life. This session aims to utilize the well-characterized interactions within our heliosphere as a 'Rosetta Stone' for elucidating the complex star-planet interactions in distant systems. Leveraging a multidisciplinary approach involving heliophysics and solar physics, we will discuss how insights from our solar system can critically inform the methodologies for identifying and characterizing exoplanetary atmospheres. Topics will span from the influence of stellar variability to the ramifications of space weather on both atmospheric retrieval processes and habitability around stars. 

Topics 

Impact of Stellar Activity on Transmission Spectra: Understanding the variable behavior of stars from the solar physics perspective, such as sunspots and starspots, faculae, flares, and coronal mass ejections (CMEs), is crucial for interpreting transmission spectra related to atmospheric retrieval. The session will delve into how these factors complicate the transmission spectral lines, and the challenges posed in distinguishing stellar activity from planetary signals. Strategies to correct or mitigate these effects to enhance our ability to detect atmospheric signals in exoplanets will be discussed.

Space Weather Effects on the Habitable Zone: The Sun is known to be the main source of transient space weather phenomena such as flares and CMEs. When they interact with planetary magnetospheres, they lead to large-scale effects such as auroras, and large areas of enhanced hazardous radiation that can affect humans. By leveraging a wealth of data from our own solar system, this topic aims to extrapolate how stellar space weather effects can alter the definition and stability of habitable zones around other stars.

Planetary Magnetic Fields and Atmospheric Erosion: Earth’s magnetic field is well known to protect our atmosphere from being swept away by solar activity. Planetary magnetospheres can be a critical factor in protecting (exo)planets from atmospheric erosion, even in the harsh environment of M dwarf stars. Case studies can include (and do not restrict to) comparisons of Earth's magnetosphere to the case of Mars’ weak remnant magnetic field, which will shed light on how magnetospheres contribute to atmospheric and/or water retention and therefore to the habitability of a planet.

Session 2: Leveraging the history of the inner solar system to inform the search for habitable and inhabited exoplanets

Overview

One of the primary motivations for the Habitable Worlds Observatory is the search for habitable and inhabited worlds. However, fundamental questions remain regarding the initial establishment and long-term maintenance of planetary habitability and the nature of habitable but non-inhabited planets, a potentially necessary comparison point for successful biosignature searches. The evolutionary histories of Earth, Mars, and Venus hold promise to illuminate the critical factors involved in establishing conditions suitable for stable surface liquid water over geologic time. Moreover, the history of early Earth contains diverse chapters describing the transformation of a planet’s atmosphere and surface environment from one dominated by abiotic processes to one where life plays an inextricable role. This session welcomes diverse expertise including, but not limited to, simulating early terrestrial atmospheres in the laboratory and in silico, examining the geochemical proxy record of terrestrial planets to enhance our understanding of early planetary environments, and simulating the magnetospheres and atmospheric loss histories of the terrestrial planets.  Work relating to the evolution of planetary interiors as they relate to surface conditions or the role of orbital dynamics in shaping habitability is also encouraged.

Topics

Atmospheric and Habitability Evolution of Inner Solar System Planets: This session focuses on the atmospheric evolution of Earth, Mars, and Venus, exploring the conditions and processes that allowed for or restricted the presence of stable surface liquid water over geologic timescales. These histories are illuminated by examining the geochemical proxy record, remote or in situ morphological or atmospheric analyses, and computational simulations.

Intrinsic Factors: Planetary Interiors and Habitability: This topic interrogates how the evolution of planetary interiors impacts surface conditions and overall habitability. Emphasis will be on the connection between planetary cores, mantles, and crusts, and their influence on factors critical for life at the surface. For example, this topic includes investigations into the importance of Earth’s magnetic field or volcanic processes for habitability and life.

Extrinsic Factors: Orbital Dynamics and Habitability: This session examines the significant role of planetary orbits and gravitational interactions in determining habitability. Entries to this topic will show how orbital dynamics influence atmospheric conditions, the potential for surface water, and other essential conditions for life. This includes, but is not limited to, investigations into the role of Earth’s moon in shaping Earth environments or how obliquity variations affected the habitability of early Mars.  

The Search for Remote Biosignatures: This session focuses on the potential for detecting distant signs of life on exoplanets, including both the origin of biosignatures, the fate of biosignatures, and observational challenges/requirements for detecting biosignatures. For example, we welcome presentations relating to biosignatures arising from Earth life throughout its history, methods for identifying possible abiotic biosignature mimics (“false positives”), or studies of the planetary scenarios most conducive to remotely detectable biospheres. While primarily centered on biosignatures, the possibility of technosignatures is within the scope of this segment.

Session 3: Cross-Domain Machine Learning Methods for Applications to Exoplanetary Atmospheric Retrieval

Overview

Building on the foundational understanding of star-exoplanet interactions, this session is more technical and gives the spotlight  to cross-domain, cutting-edge machine learning (ML) techniques that can help with the identification of exoplanetary atmospheres. This session widens the scope to other domains of application of ML  (e.g., biology, medicine, finance)  where it can surmount the challenges posed by noisy or ambiguous data contaminated by unwanted sources. We seek cross-domain fertilization to yield more accurate atmospheric detections and characterizations, as atmospheric retrieval so far comes down to finding the needle in a stellar-contaminated haystack. This session will foster interdisciplinary dialogue and collaboration among data scientists from all domains, astrophysicists, and planetary scientists. We invite you to join this stimulating session to identify future avenues of research where ML can make a significant impact in the field of exoplanetary atmospheric study.

Topics

Machine Learning for Spectral Analysis and Classification: This segment will focus on how machine learning techniques, particularly supervised algorithms like Support Vector Machines (SVM) and Random Forests, can be used to analyze and classify exoplanetary atmospheres based on their spectral data. This topic will also touch upon feature extraction and the importance of identifying relevant spectral lines for accurate classification.

Neural Networks for Atmospheric Parameter Estimation: The session will explore the application of neural network architectures, including convolutional and recurrent neural networks, for estimating key atmospheric parameters. These can range from temperature profiles to chemical compositions, providing a comprehensive characterization of the exoplanetary atmosphere.

Unsupervised Learning and Anomaly Detection: Without in-situ measurements of an exo-atmosphere, there is no such thing as “ground truth” that we can give to an advanced ML method to perfectly evaluate its accuracy. Thus this session must also delve into unsupervised learning methods such as clustering and outlier detection algorithms for identifying unique or anomalous atmospheric signatures. This topic aims to highlight the utility of machine learning in discovering new phenomena or rare atmospheric configurations that may not be easily discernible through conventional methods.

Session 4: Bridging Communities: Theory and Experiments Collide to Tackle Exoplanet Research Challenges

Overview

In this session, we will shift our focus towards the critical needs in the exoplanet -- and solar system! -- research communities that could be addressed with enhancing communication and collaboration between theoretical and experimental scientists. In addition, this session will offer insights into the experimental side of exoplanet research, where cutting-edge technology and techniques bring us closer to interpreting the valuable data gathered with space and ground-based telescopes. We will work towards identifying the specific needs within the theoretical and experimental communities and by recognizing these needs we can pinpoint areas for prioritization, improvement, and innovation. This session will encourage an open dialogue between theorists and experimentalists, fostering collaboration and knowledge sharing. Together, we will identify the research needs that will drive our understanding of exoplanet atmospheres and formation to new frontiers.

Topics

Techniques necessary to simulate the environments of exoplanets: Explore the latest techniques in laboratory spectroscopy measuring their composition, temperature, and physical properties. Gain insights into the controlled experiments conducted in laboratories to mimic the extreme conditions found on exoplanets. These experiments allow researchers to test theoretical models and refine their understanding of exoplanetary processes. Explore the innovative technologies and instruments that scientists are designing to improve exoplanet observations, from advanced spectrographs to specialized telescopes.

Chemistry is a way of life: Join us for an in-depth exploration of the chemical composition and processes that shape exoplanets, and the essential laboratory techniques required. Explore the laboratory experiments that replicate the extreme conditions found on exoplanets, including high pressures and temperatures. Understand how these experiments reveal the chemistry that occurs in exoplanetary atmospheres and interiors.