Overview

• A peer-reviewed Nature Communications paper published on September 1, 2025 by a team led by Jonas Rabia reports the confirmed detection.
• The footprint was captured during Juno’s 22nd orbit in September 2019 when a high‑density solar stream pushed Jupiter’s main auroral oval toward the equator.
• At the same time, Juno crossed the magnetic field line connecting Callisto to Jupiter, allowing ultraviolet imaging linked to the moon.
• Juno’s instruments sampled charged particles, electromagnetic waves, and magnetic‑field variations associated with the interaction.
• The result completes the set of auroral signatures from Io, Europa, Ganymede, and Callisto, clarifying why Callisto’s faint signal had long been obscured by the brighter main oval.