3I/ATLAS mission: ESA spacecraft set to fly through interstellar tail

s per new study, two ESA spacecraft, Hera and Europa Clipper, will fly through 3I/ATLAS

By Aqsa Qaddus Tahir
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October 25, 2025
3I/ATLAS mission: ESA spacecraft set to fly through interstellar tail

Since its discovery on July 1, mysterious interstellar object 3I/ATLAS have baffled the scientists with its origin and nature of tail, whether it is comet or alien probe.

To solve the perplexing nature, two European Space Agency (ESA) spacecraft are poised for a rare fly-through of 3I/ATLAS to detect ions emitted from interstellar’s tail as it approaches the sun on October 29, suggested by a new research study.

Two spacecrafts named as Hera and Europa Clipper, are on their way to missions in our solar systems.

Hera is responsible for observing Didymos-Dimorphos, a binary asteroid affected by the Dart mission in 2022.

On the other hand, Europa Clipper, is studying the ice on Europa, one of Jupiter's four Galilean moons.

Fortunately, both spacecraft will pass “downwind” of 3I/ATLAS within the next two weeks. Hera’s window will be between October 25th to November 1st and Europa Clipper will have a window between October 30th and November 6th.

Since interstellar comet discovery, its tail has constantly been growing and showing unusual features, such as gushing of water and releasing of ions. Its tail is expected to grow until the comet reaches perihelion on October 29th.

Here is the catch! Tail’s trajectory is not a simple path as it is riddled with solar winds. These winds can push tail particles away from the sun and cause them to follow curved pathways.

Therefore, the speed of solar wind will be a major roadblock in determining the path of tail particles and collecting direct data.