Astrometric Detectability of Habitable Exoplanets: An Open-Source Framework Using Gaia DR3

In this paper, I investigate the astrometric detection limits for potentially habitable exoplanets orbiting within 100 parsecs in the solar neighborhood. Using Gaia DR3 data, I developed a model that uses parallax, photometry, and stellar parameters to estimate the minimum detectable astrometric signature per star. The model assesses data across a range of stellar types with corresponding planetary data, accounting for instrumental uncertainty and a conservative jitter floor to model astrophysical noise. The pipeline reveals that while Gaia can currently detect habitable Jupiter-analogs around hundreds of nearby stars, Earth, Super-Earth, and Sub-Neptune analogs remain out of reach due to current astrometric detection thresholds. The objective of this paper, therefore, is to provide a snapshot of Gaia’s current detection limit and to assess the landscape of habitable worlds detection in the near future with this scalable framework.