ESA unveils new mission 'Comet Interceptor' to scrutinise inner solar system's space rocks

European Space Agency (ESA), on June 8, unveiled its new mission named 'Comet Interceptor,' which would scrutinise a comet that once lingered in inner solar system or is new to it. This mission was proposed in July 2018 and has now been opted after completion of its study phase. ESA revealed that it will soon begin development of mission after selecting a prime contractor for a spacecraft. 

When will mission Comet Interceptor launch?

Comet Interceptor spacecraft will be launched in 2029 in a ride-share mission with ESA's Ariel (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) probe. Ariel is being designed to study formation and evolution of exoplanets by surveying a diverse sample of about 1000 extrasolar planets, simultaneously in visible and infrared wavelengths. Notably, Ariel would be first mission dedicated to measuring chemical composition and rmal structures of exoplanets.

As for Comet Interceptor, it is a ‘fast’ or F-class mission, which weighs less than 1000 kg and takes only about eight years from option to launch. Once launched, both Interceptor and Ariel will be sent at second Lagrange point (L2), which is 1.5 million km behind Earth as viewed from sun. 

Mission profile

Interceptor spacecraft will be installed at L2 to spot and select a comet that has spent some time in inner solar system. Interceptor will be me of three components -- main spacecraft and two smaller probes. While one of probes will be developed by ESA, or will be a contribution by Japan Aerospace Exploration Agency (JAXA). 

After Interceptor spots a target, it will release two probes to extract information about nature of target comet through ir multiple high-tech instruments. During entire course of mission, Interceptor will characterise target's surface composition, shape and structure for first time ever, and investigate composition of its gas and dust. ESA says that this mission will build on progress of its Rosetta and Giotto probes that visited ‘short-period’ comets.

agency also highlighted that while Rosetta's target emerged from  rocky Kuiper Belt just beyond Neptune, Interceptor's target could hail from Oort cloud, which is far beyond our solar system. Scientists believe that studying a target from outside our solar system would offer chance to explore how comet-like bodies form and evolve in or star systems.

(Kuiper belt and Oort cloud illustration; Image: ESA)