Bioverse: a simulation framework to assess the statistical power of future biosignature surveys

TL;DR

Bioverse is a simulation framework designed to evaluate the statistical power of future space observatories in detecting population-level properties of terrestrial exoplanets and assessing planetary habitability.

Contribution

It introduces a novel simulation and hypothesis testing framework that combines exoplanet statistics with survey modeling to inform the design of next-generation biosignature surveys.

Findings

Large search volumes are necessary to study rare Earth-like habitable zone planets.

Bioverse can evaluate the capability of proposed surveys to detect statistical relationships.

The framework aids in optimizing future observatory designs for population-level exoplanet studies.

Abstract

Next-generation space observatories will conduct the first systematic surveys of terrestrial exoplanet atmospheres and search for evidence of life beyond Earth. While in-depth observations of the nearest habitable worlds may yield enticing results, there are fundamental questions about planetary habitability and evolution which can only be answered through population-level studies of dozens to hundreds of terrestrial planets. To determine the requirements for next-generation observatories to address these questions, we have developed Bioverse. Bioverse combines existing knowledge of exoplanet statistics with a survey simulation and hypothesis testing framework to determine whether proposed space-based direct imaging and transit spectroscopy surveys will be capable of detecting various hypothetical statistical relationships between the properties of terrestrial exoplanets. Following a description of the code, we apply Bioverse to determine whether an ambitious direct imaging or transit survey would be able to determine the extent of the circumstellar habitable zone and study the evolution of Earth-like planets. Given recent evidence that Earth-sized habitable zone planets are likely much rarer than previously believed (Pascucci et al. 2019), we find that space missions with large search volumes will be necessary to study the population of terrestrial and habitable worlds. Moving forward, Bioverse provides a methodology for performing trade studies of future observatory concepts to maximize their ability to address population-level questions, including and beyond the specific examples explored here.