JANUS, the optical camera on ESA's JUICE probe, captures stunning images during its first lunar and terrestrial flyby

JANUS, the optical camera on ESA's JUICE probe, captured stunning images of the Earth and Moon during its first lunar and terrestrial flyby. This high-risk manoeuvre, successfully completed between 19-20 August, allowed JUICE to alter its speed and direction for a close flyby of Venus in August 2025. This critical step is part of JUICE's journey through the inner Solar System towards its final destination: the moons of Jupiter. 

SETTING UP THE JANUS CAMERA

The JANUS (Jovis, Amorum ac Natorum Undique Scrutator) camera is designed to study the morphology of Jupiter's icy moons, their global, regional and local processes, and to map the surface of the gas giant's clouds. 

The Earth as seen at sunrise on 20 August 2024 by the JANUS optical camera on board JUICE.  Credit: JANUS team (INAF, ASI, DLR, IAA-CSIC, Open University, CISAS-University of Padua, and other international partners).

READY TO OBSERVE JUPITER'S ATMOSPHERE

As with the Moon, observing the surfaces of Jupiter's icy moons is not hampered by an atmosphere. On the contrary, Jupiter does have a massive, dynamic and turbulent atmosphere. The images of the Earth taken by JANUS, through different filters, serve as a test for future observations of the Jovian atmosphere. By simply changing the filter, it will be possible to observe various layers and components of Jupiter's atmosphere. This capability will allow the complex atmospheric dynamics of the planet to be studied in a way that is not possible with single-band images.

THIRTEEN FILTERS

The Italian instrument has 13 filters distributed over the spectral range from visible to near-infrared (0.34 - 1.08 microns). Having images of the same area in different filters allows much more than just ‘colour’ images: everyday cameras acquire images with three different filters (red, green and blue or RGB) arranged in a checkerboard pattern on the same sensor, while JANUS positions 13 filters in front of the detector, covering a wider range than is perceptible to the human eye.

JANUS will capture multispectral images of Jupiter's icy moons with 50 times the resolution and coverage of previous cameras sent to the Jupiter system. The camera is equipped with an on-board computer that manages all instrument functions, processes commands and sends telemetry and data back to Earth via JUICE's large dish antenna. This advanced capability will significantly improve the understanding of these distant celestial bodies.

The Moon as captured by the JANUS camera on board ESA's JUICE probe. Near the terminator (the line between day and night on the lunar surface), sunlight is grazing, highlighting valuable details for geological interpretation of the surface if the instrument's dynamic range (the ability to distinguish many levels of light intensity) is sufficiently wide. Credit: JANUS team (INAF, ASI, DLR, IAA-CSIC, Open University, CISAS-University of Padua, and other international partners).

ABOUT JANUS

Leonardo SpA is the industrial leader responsible for the design, integration and testing of the JANUS instrument, with subsystem contributions from DLR in Berlin, IAA-CSIC in Granada and CEI-Open University in Milton Keynes. The Italian, German and UK space agencies (ASI, DLR and UKSA), together with the Spanish Ministry of Research, are the main funders of the project. JANUS was developed by an international team composed of institutes and researchers from Italy, Germany, Spain, Great Britain, France, USA, Japan and Israel, demonstrating the power of global collaboration in advancing space exploration. INAF is leading the scientific team.

AUDIO-VISUAL MATERIAL

DISCLAIMER: THE IMAGES PUBLISHED TODAY ARE PRELIMINARY AND HAVE NOT BEEN PROCESSED FOR SCIENTIFIC USE.

You can download all the images here: https://drive.google.com/drive/folders/1tRCF35AUWWigsrgG-buOxgITpTaKlP9f?usp=drive_link

Description and Image Credits: https://docs.google.com/document/d/1gFVxnCKc5_X6vc0ZXmondyOStKT-jnYC/edit?usp=sharing&ouid=113982860598267029130&rtpof=true&sd=true

You can download videos here: https://drive.google.com/drive/folders/1a3mGnCywvnnQBXfn_ZfErZ_Bd3L_ILyT?usp=sharing