The Castalia Space Mission

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Castalia is a proposed mission for the ESA M5 (medium sized mission) call.

The Castalia Space Mission will be launched in the late-2020s, to go and explore Comet 133P/Elst-Pizarro, a Main Belt Comet.

Main Belt Comets (MBCs) are a newly identified population in the Asteroid Main Belt. Their orbit are undistinguishable from those of the asteroids, but they display cometary activity —a dust coma or a dust tail.  133P/Elst-Pizarro behaves like a normal comet: its cometary activity happens regularly while it passes through perihelion, i.e. when it is closest to the Sun. The most likely explanation is that some water ice is buried in its nucleus, and starts sublimating when it is heated by the Sun.

Comet 133P/Elst-Pizarro
NTT, ESO La Silla, 3 September 2013

Castalia  will study the nature of this comet, and illuminate the role of the MBCs in the overall planetary formation and during the early ages of the solar system. Furthermore, Castallia will explore the connection of MBCs with the origin of water on Earth.

The mission will be launched towards the end of the 2020s. The spacecraft will travel 5-10 years before reaching the comet several months before the cometary activity starts. It will study the nucleus and observe the onset of the activity, and then will probe the dust and gas released by the comet.

The technology for the spacecraft and for the instrument is either available today , or is at a suitable level of readiness for successful implementation
The spacecraft envelope and financial budget of the Castalia mission is at the level of a typical ESA M-class mission.

The design of the mission and the spacecraft were developed by the science team and by the Institute of Space Systems / System Analysis Space Segment (DLR) and OHB System.


These pages present the key questions that the mission will address, the spacecraft and its instrumentation, and the profile of the space mission:
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