The study investigates the production and loss of hydrogen (H₂) and oxygen (O₂) from Europa's water-ice surface, which is modified by exposure to Jupiter's space environment. Charged particles break molecular bonds in the surface ice, dissociating water into H₂ and O₂. These species are expected to be the primary atmospheric constituents. Remote observations have provided global constraints on Europa's atmosphere, but the molecular O₂ abundance has been inferred from atomic O emissions, with estimates ranging over several orders of magnitude. The Juno mission's observations directly confirm the presence of H₂⁺ and O₂⁺ pickup ions from the dissociation of Europa's water-ice surface, confirming them as primary atmospheric constituents. Contrary to expectations, the H₂ neutral atmosphere is dominated by a non-thermal, escaping population. The study finds that 12 ± 6 kg s⁻¹ (2.2 ± 1.2 × 10²⁶ s⁻¹) of O₂ are produced within Europa's surface, which is less than previously thought and supports a narrower range for habitability in Europa's ocean. This process is identified as the dominant exogenic surface erosion mechanism over meteoroid bombardment. The findings also suggest that the atmospheric neutral population is not thermalized, and the H₂ neutral altitude profile and total derived H₂ loss rates are independently consistent, indicating that the H₂ population is heated after release from the surface by an additional mechanism. The overall budget of 12 ± 6 kg s⁻¹ total O₂ produced in the surface is partitioned into atmospheric loss and potential sequestration into the surface ice, providing constraints on the pathways for O₂ production and its availability to the subsurface ocean.The study investigates the production and loss of hydrogen (H₂) and oxygen (O₂) from Europa's water-ice surface, which is modified by exposure to Jupiter's space environment. Charged particles break molecular bonds in the surface ice, dissociating water into H₂ and O₂. These species are expected to be the primary atmospheric constituents. Remote observations have provided global constraints on Europa's atmosphere, but the molecular O₂ abundance has been inferred from atomic O emissions, with estimates ranging over several orders of magnitude. The Juno mission's observations directly confirm the presence of H₂⁺ and O₂⁺ pickup ions from the dissociation of Europa's water-ice surface, confirming them as primary atmospheric constituents. Contrary to expectations, the H₂ neutral atmosphere is dominated by a non-thermal, escaping population. The study finds that 12 ± 6 kg s⁻¹ (2.2 ± 1.2 × 10²⁶ s⁻¹) of O₂ are produced within Europa's surface, which is less than previously thought and supports a narrower range for habitability in Europa's ocean. This process is identified as the dominant exogenic surface erosion mechanism over meteoroid bombardment. The findings also suggest that the atmospheric neutral population is not thermalized, and the H₂ neutral altitude profile and total derived H₂ loss rates are independently consistent, indicating that the H₂ population is heated after release from the surface by an additional mechanism. The overall budget of 12 ± 6 kg s⁻¹ total O₂ produced in the surface is partitioned into atmospheric loss and potential sequestration into the surface ice, providing constraints on the pathways for O₂ production and its availability to the subsurface ocean.