mountain profile Institute for Astronomy University of Hawaii



Maintained by WW

Does Earth's water originate from comets?

Comets provide one of the mechanisms for large-scale transport and delivery of water within our solar system, and asteroids provide another source of volatiles. However, neither comets nor asteroids can explain both Earth's water and its noble gas inventory. A recently discovered new class of icy bodies in the outer asteroid belt, the main-belt comets (MBCs), may be the key. Dynamics suggest they formed in situ, beyond the primordial snow line, and as such represent a class of icy bodies that formed at a distance from the Sun that has not yet been studied in detail and that could potentially hold the key to understanding the origin of water on terrestrial habitable worlds.  Karen Meech  and her team is developing a Discovery satellite mission concept to explore ices in the outer asteroid belt.



Manx Comets

Manx objects are small bodies following long-period comet orbits from the Oort cloud to the inner solar system, but which have little or no comet activity (i.e. tailless like the Manx cat). Spectroscopically, they are similar to rocky inner solar system asteroids, but they have a small level of comet activity.


The Pan-STARRS survey has been exceptional at discovering Manx comets with low activity levels at a variety of distances.   These may represent inner solar system material that built our habitable planet.  Karen Meech's team is studying all new Manxes discovered by PanSTARRS.