ESA | Space Science | Science & Technology | 2019 Jun 19
'Comet Interceptor' has been selected as ESA's new fast-class mission in its Cosmic Vision Programme. Comprising three spacecraft, it will be the first to visit a truly pristine comet or other interstellar object that is only just starting its journey into the inner Solar System.
The mission will travel to an as-yet undiscovered comet, making a flyby of the chosen target when it is on the approach to Earth's orbit. Its three spacecraft will perform simultaneous observations from multiple points around the comet, creating a 3D profile of a 'dynamically new' object that contains unprocessed material surviving from the dawn of the Solar System. ...
Comet Interceptor is a 'fast', or F-class mission. The 'fast' refers to the implementation time, with a total development duration from selection to launch readiness of about eight years. F-class missions, which have a launch mass of less than 1000 kg, will share the ride into space with a medium-class mission, taking advantage of additional space in the launcher and the boost to the Sun-Earth Lagrange point L2, which is 1.5 million kilometres 'behind' Earth as viewed from the Sun.
Comet Interceptor is foreseen for launch as co-passenger with ESA's exoplanet-studying ARIEL spacecraft in 2028. Both missions will be delivered to L2 and from there Comet Interceptor will journey onwards to the chosen target using its own propulsion system. ...
Comet Interceptor comprises three spacecraft. The composite spacecraft will wait at L2 for a suitable target, then travel together before the three modules separate a few weeks prior to intercepting the comet. Each module will be equipped with a complementary science payload, providing different perspectives of the comet’s nucleus and its gas, dust, and plasma environment. Such ‘multi-point’ measurements will greatly improve the 3D information needed to understand the dynamic nature of a pristine comet while it is interacting with the constantly changing solar wind environment.
The mission’s instrument suite will draw on heritage from other missions, including a camera based on the one currently flying on the ExoMars Trace Gas Orbiter, along with dust, fields and plasma instruments, as well as a mass spectrometer, like those that flew on ESA’s Rosetta. ...
Comet Interceptor is different because it will target a comet visiting the inner Solar System for the first time – perhaps from the vast Oort cloud that is thought to surround the outer reaches of the Sun's realm. As such, the comet will contain material that has not undergone much processing since the dawn of the Sun and planets. The mission will therefore offer a new insight into the evolution of comets as they migrate inwards from the periphery of the Solar System.
Although much rarer, another example of a potential target is an interstellar interloper from another star system, like the famed 'Oumuamua that flew past our Sun on a highly inclined orbit in 2017. Studying an interstellar object would offer the chance to explore how comet-like bodies form and evolve in other star systems. ...
Space Mission to Chase Comet Will Be Led by UK Scientists
UK Space Agency | 2019 Jun 20