The ESA has given the green light for a mission in which three spacecraft go deep into our solar system in 2028 towards a comet that is just entering our solar system. The goal is to make a 3D model of it and to find out more about the celestial body.
The mission is called Comet Interceptor and consists of three spacecraft. They initially form a whole, but they are split up for mapping out a comet or other object – it is not yet known exactly which Comet Interetor will investigate. By splitting into three vessels, photos are taken from different perspectives. On the basis of this, a 3D model will eventually be made, which should help the ESA to recognize material from the very beginning of the solar system. Various instruments are included, such as a mass spectrometer and a camera.
The intention is for Comet Interceptor to ride along with another ESA spacecraft launched in 2028. This concerns Ariel, a spacecraft that will study exoplanets. Both missions are on their way to LaGrange point L2, 1.5 million kilometers from Earth. From that point, the Comet Interceptor spacecraft, which has a total mass of less than 1000 kg, will continue to fly on its own with its propulsion system.
The ESA says that it is a unique mission, because for the first time a comet will be photographed that will visit the inner part of the solar system for the first time. Earlier comet missions, such as Giotto and Rosetta, studied comets that had traveled around the sun many times. Comet Interceptor, on the other hand, will focus on a ‘pristine’ comet that has changed little since the time the sun and the planets were formed. That could provide insight into the formation of comets when they fly to the center of the solar system. The object on which the mission focuses can come from the Oort cloud, a supposed large cloud around our solar system with billions of rocky objects.
No object has been selected as a target for this mission yet; the ESA says that the destination for the mission does not have to be known in advance, since the spacecraft can be in space standby, waiting for a good opportunity to intercept a comet. The detection capacity for scanning the space from the earth has also made considerable leaps. In the past, ‘new’ comets were discovered a few months or years before they came to the closest point to the sun in their orbit. That made planning a space mission such as that of Comet Interceptor impossible because there was insufficient time. Now, however, there would be enough time for the spacecraft to spontaneously take action if a suitable candidate is spotted from Earth.
This terrestrial capacity for mapping comets early is mainly about Pan-Starrs, a system specifically designed to detect near-Earth objects. The system consists of two 1.8 m telescopes and is located in the Haleakala Observatory in Hawaii, with which part of the sky is observed every night. The Large Synoptic Survey Telescope, currently being built in Chile, will also make a major contribution to finding new comets.