Interstellar comet 3I/ATLAS is captured by Hubble and Juice in recent observations

Telescópio Espacial Hubble and the Juice probe, from Agência Espacial Europeia (ESA), recorded new images of the interstellar comet 3I/ATLAS. The observations took place in November, revealing details of the object’s coma and tails.

The comet, the third confirmed origin outside Sistema Solar, was discovered on July 1, 2025 by the ATLAS telescope at Chile. Ele follows a hyperbolic trajectory, confirming its interstellar origin.

The captures provide data on the composition and dynamics of bodies formed in other stellar systems.

• The Juice probe observed the comet on November 2, from about 66 million kilometers away.
• The navigation camera image shows the bright core surrounded by a coma of gas and dust.
• A plasma tail extends upward, formed by the ionization of gases by the solar wind.

Observations from probe Juice

The Juice mission, aimed at Júpiter, used five scientific instruments to study 3I/ATLAS.

Complete data will only reach Terra in February 2026, as the main antenna serves as a heat shield against Sol.

Engineers sent a partial preview via secondary antenna.

The observation occurred shortly after the comet’s perihelion, on October 30, when activity was intense.

Images of Telescópio Hubble

Hubble recorded the comet on November 30, 286 million kilometers from Terra.

Wide Field Camera 3 captured a bright central nucleus surrounded by dust.

Background stars appear as dashes as the telescope followed the comet’s rapid movement.

These images confirm continued activity, similar to initial observations in July.

Comet characteristics

3I/ATLAS presents atypical properties compared to Sistema Solar comets.

• Dust grains show different sizes from locations.
• High proportion of carbon dioxide in relation to water.
• Gases rich in nickel compared to iron.

These features suggest distinct formation conditions in another star system.

Trajectory and origin

The comet travels at high speed, with an orbit that will take it back to interstellar space.

Its entry speed indicates possible origin in an ancient planetary system.

Does not pose a risk to Terra, maintaining safe distances.

Details of the observed tails

The Juice images reveal two distinct tails.

The plasma tail points away from Sol, driven by the solar wind.

A more subtle dust tail extends in the opposite direction.

These structures highlight the interaction with solar radiation.

Scientific contributions

The combined observations of Hubble and Juice enrich the understanding of interstellar objects.

Data complements multiple mission campaigns, including ships in Marte and heliophysics.

Research focuses on the unusual chemistry and evolution of the activity.