The UK Space Agency mission will look for companies to build a spacecraft and a robotic probe for what will be the first mission from Earth to travel to a comet which has never previously encountered the inner solar system.
Today the Comet Interceptor mission was formally approved by the European Space Agency (ESA).
Carrying two robotic probes on board, the spacecraft will blast off and travel to a comet from the Oort Cloud – the most distant region of our solar system – in order to map it in three dimensions.
The exact comet has not yet been identified but the aim is to “not only further our understanding of the evolution of comets but help unlock the mysteries of the universe,” said Caroline Harper, head of space science at the UK Space Agency.
After being adopted by the ESA in Madrid today, the mission now moves from the design phase to implementation, with the selection of a contractor to build the spacecraft and one of the robotic probes, with the other already designed by Japan's JAXA space agency, ahead of planned launch in 2029.
Professor Geraint Jones, from the UCL Mullard Space Science Laboratory, said: “We should get our first glimpse of a truly pristine body with this mission – an invaluable example of the objects that came together to form the Earth and other planets.
“The comet’s surface will be largely unchanged since the time of the Solar System’s formation several billion years ago, and I can’t wait to see that uncharted territory sometime in the 2030s.”
ESA approval comes four years since its invitation was delivered.
Designing and building the spacecraft before the target is even discovered is a "completely new approach" for such space missions, said Professor Colin Snodgrass, from the University of Edinburgh.
He said it would open up "opportunities to visit space objects that were completely inaccessible before, such as comets entering the inner solar system for the very first time, or possibly even interstellar objects that formed around a distant star".
The UK Space Agency has so far provided £2.3mln in funding for the Fluxgate Magnetometer, being developed by Imperial College London, and a Modular InfraRed Molecules and Ices Sensor (MIRMIS) instrument, led by the University of Oxford.
MIRMIS will deliver a unique dataset, providing information such as the comet’s shape, size and rotation state, while the Fluxgate Magnetometer sensor aims to provide high accuracy and high-time resolution measurements of the comet’s magnetic field size and direction.
According to NASA, although comets observed among the planets are thought to originate in the Oort Cloud, "no object has been observed in the distant Oort Cloud itself, leaving it a theoretical concept for the time being".