On 28 September, ESA’s Juice mission reached another important Jupiter-bound milestone with its penultimate gravity assist manoeuvre: a flyby of Earth. This encounter, however, was not only an essential step on the road to Jupiter, but an opportunity to rehearse the observations and operations that will define Juice’s exploration of the Jovian system.
ESA’s Jupiter Icy Moons Explorer (Juice) has successfully completed a world-first lunar-Earth flyby, using the gravity of Earth to send it Venus-bound, on a shortcut to Jupiter through the inner Solar System.
Enceladus is a prime target in the search for life in our solar system, having an active plume likely connected to a large liquid water subsurface ocean.
Using the sensitive NIRSpec instrument onboard JWST, we searched for organic compounds and characterized the plume’s composition and structure. The observations directly sample the fluorescence emissions of H2O and reveal an extraordinarily extensive plume (up to 10,000 km or 40 Enceladus radii) at cryogenic temperatures (25 K) embedded in a large bath of emission originating from Enceladus’ torus.
The instrument Jovis, Amorum ac Natorum Undique Scrutator (JANUS) passed the commissioning phase with full marks. It is a real test during which – 8 million km from the Earth – it opened its electronic “eyes”, sending the so-called “first light”, i.e. his first series of images, to the technicians and researchers
