Two spacecraft, Hera and Europa Clipper, are poised to embark on a groundbreaking mission, passing through the tail of comet 3I/ATLAS. This interstellar visitor, discovered in early June, has captivated scientists with its growing tail, which is now gushing water and leaving a trail of ions behind. The comet's tail has been consistently expanding as it approaches the Sun, and it is expected to reach its peak on October 29th, when it reaches perihelion. The challenge lies in the comet's unique path; as it moves through the solar system, the solar wind pushes particles out in a curved path, creating a complex trajectory for the spacecraft to follow. The authors of a recent paper, Samuel Grand and Geraint Jones, propose a daring plan to utilize these spacecraft to study the comet's tail. The spacecraft will have to pass through a specific region of the tail, where the solar wind's impact on particles is crucial to understanding the comet's behavior. The 'Tailcatcher' model, used to estimate the path of cometary ions, indicates that the spacecraft must be positioned at a precise distance from the central axis of the tail. Despite the limited time available, the mission could provide invaluable insights into the comet's composition and its interaction with the solar wind. However, the plan is not without challenges. One spacecraft, Hera, lacks the necessary instruments to detect the ions and magnetic field changes in the comet's tail. Europa Clipper, on the other hand, is equipped with a plasma instrument and magnetometer, making it the ideal candidate for this mission. The success of this endeavor hinges on the swift action of mission controllers, who must recognize the potential of this opportunity. If they act promptly, these spacecraft could become the first to directly sample an interstellar comet's tail, marking a significant achievement in space exploration.
