The European Space Agency's JUICE mission pointed its instruments at 3I/ATLAS. This body, only the third of its kind ever detected, is currently leaving our Solar System after passing through it.
To gather information, JUICE deployed five of its instruments, including the JANUS camera. During November 2025, these tools recorded images and spectrometric data, in order to determine the nature of this cosmic visitor. The probe's position, located on the far side of the Sun from Earth, complicated data transmission. Scientists had to wait several weeks before they could analyze the first images, delaying the initial analysis.
The European Space Agency's JUICE probe obtained its first detailed image of the interstellar comet 3I/ATLAS, capturing a bright coma and a long tail.
Image credit: ESA/Juice/JANUS The obtained image reveals a comet with a bright coma and an extended tail. These features form when ice in the cometary nucleus heats up due to the Sun, releasing a cloud of gas and dust that stretches out into space.
Interstellar comets like 3I/ATLAS are rare, but their examination allows for comparing their composition with that of comets originating in our own Solar System. Such an approach helps determine whether planetary formation processes are similar elsewhere in the galaxy.
The research teams plan to meet in late March to discuss their findings. A thorough examination of the comet's composition could yield clues about the materials present in other star systems.
Space Data Transmission
Space probes like JUICE send information to Earth via radio signals. These transmissions must travel vast distances, which can take several minutes, or even hours, depending on the relative position. For JUICE, during the observation of comet 3I/ATLAS, the distance was about 41 million miles (approximately 66 million kilometers).
Engineers use large, sensitive parabolic antennas to capture these weak signals. The transmission rate depends on the available bandwidth and power on the probe. In JUICE's case, the presence of the Sun between the probe and Earth created interference, requiring additional delays to ensure reception.
Once the data is received on Earth, it is decoded and verified to avoid errors. Engineers then analyze it with specialized software, looking for patterns or anomalies. This entire process can take weeks, as it did for the 3I/ATLAS images, before the results are shared with the scientific community.
These communication methods are fundamental for all exploration missions, enabling the reporting of discoveries from the far reaches of the Solar System. They are constantly evolving with technological advances, improving the reliability and speed of exchanges.