The Earth and other terrestrial planets orbit the Sun within a cloud of interplanetary dust. This so-called zodiacal cloud is thought to comprise of dust of asteroidal, cometary and possibly interstellar origin. However, despite its proximity, the detailed structure of the zodiacal cloud is not well understood, and there remains considerable uncertainty over the dynamical processes that shape it. Better understanding of our zodiacal cloud is important not only in its own right, but also because such clouds are expected to be a common feature of exoplanetary systems.
Using long-term optical observations from the two spacecraft of the STEREO mission, we (a collaboration between the OU and UCLan) are studying the structure of the zodiacal cloud in greater detail than has ever been previously attempted. A notable success of this project was the first imaging of a dust ring around the orbit of Venus, a finding that has now led to the surprising finding that the structure of this ring varies with time. We are continuing this work to map the large-scale structure of the zodiacal cloud interior to the Earth’s orbit.