Key Highlights
- Two ESA spacecraft, Hera and Europa Clipper, are set to pass through the tail of interstellar comet 3I/ATLAS.
- The mission aims to collect data on cometary ions from the comet’s spectacular tail as it approaches the Sun.
- The opportunity arises due to both spacecraft passing “downwind” of the comet in the next two weeks.
- Neither spacecraft was originally designed for this task, making the endeavor particularly challenging.
New Opportunity for Spacecraft to Sample Interstellar Comet’s Tail
The European Space Agency (ESA) is eyeing a unique opportunity: the upcoming passage of two of its spacecraft through the tail of interstellar comet 3I/ATLAS. This serendipitous event could provide unprecedented insights into the nature and composition of these rare celestial visitors.
Comet 3I/ATLAS – An Interstellar Intruder
Discovered in early June, 3I/ATLAS was initially hailed as a potential alien spacecraft due to its unusual behavior. However, subsequent observations revealed that it is an interstellar object, one of three known to have entered our solar system from beyond.
The comet’s tail has been consistently growing since its discovery and recent reports indicate that it is “gushing” water in massive amounts. This activity suggests the tail could be a rich source of data for scientists studying cometary science and the solar wind interaction.
ESA’s Hera and Europa Clipper
The two spacecraft at play here are Hera and Europa Clipper, both en route to their respective destinations. Hera is scheduled to impact the binary asteroid Didymos-Dimorphos in 2024, while Europa Clipper intends to study Jupiter’s moon Europa.
Both spacecraft will have a window of opportunity within the next two weeks to potentially sample ions from the comet’s tail. Hera has a window between October 25th and November 1st, while Europa Clipper’s window is between October 30th and November 6th.
A Challenge in the Making
The plan hinges on the spacecraft detecting cometary ions as they spread over millions of kilometers from the comet. Hera lacks the necessary instruments to detect these ions, but Europa Clipper has the plasma instrument and magnetometer needed for such a mission.
However, the timing is critical. The model used by scientists suggests that the spacecraft would need to pass within 8 million kilometers of the central axis of the comet’s tail to collect data. This distance, while close enough to be viable, poses significant challenges in terms of planning and execution.
The Scientific Potential
If successful, this mission could mark a historic first: directly sampling an interstellar comet’s tail. The implications are vast, offering new insights into the composition and behavior of these rare visitors from beyond our solar system. Such data could rewrite what we know about the early Milky Way and the origins of life in the cosmos.
The opportunity is fleeting, with mission controllers for Hera and Europa Clipper having a narrow window to act. Whether they choose to capitalize on this chance will determine if these spacecraft can provide groundbreaking science or remain focused on their original missions.
