The discovery and characterization of thousands of exoplanets by missions such as Kepler, TESS, CHEOPS, and JWST, along with upcoming missions like PLATO and ARIEL, has revolutionized our understanding of planetary diversity. Among the detected exoplanets are intriguing rocky worlds within the habitable zone of their stars, where atmospheric conditions could play a decisive role in sustaining life. Characterizing these atmospheres is therefore critical, particularly in identifying potential biosignatures like oxygen and ozone, which on Earth are primarily associated with biological activity. However, abiotic pathways, such as the photolysis of CO₂, can also generate molecular oxygen, complicating the interpretation of observational data. To address these challenges, we employ the Berlin Atmospheric Simulation Experiment (BASE, figure 1 and Hofmann et al., 2024), a state-of-the-art chamber designed to recreate a variety of planetary atmospheric conditions, from environments like Venus' cloud deck to thin, Mars-like atmospheres. BASE enables precise control over pressure (ranging from 1 bar to a few mbar) and temperature (260–373 K) and incorporates a sophisticated gas mixing system to set specific atmospheric compositions, including trace gases and water vapor. A key feature of BASE is its capability to simultaneously expose gas mixtures to UV, Lyman-alpha radiation, and electron irradiation — an essential factor in studying photochemical and radiative processes relevant to exoplanetary atmospheres. Our latest results highlight the formation and destruction of ozone under varying conditions, offering valuable insight into its potential role as a biosignature. Ongoing and future studies under diverse stellar radiation fields, varying atmospheric compositions, and elevated temperatures provide further understanding of photochemical pathways. By combining experimental results with atmospheric modeling, BASE contributes to refining our understanding of exoplanetary atmospheres and their potential for habitability.