In general, are carbonaceous chondrites (CC) or comets more water rich?
I know that evidence has suggested that both CC and comets are partly composed of water, but which body is generally more water rich?
Astronomy Stack Exchange is a question and answer site for astronomers and astrophysicists. It only takes a minute to sign up.Sign up to join this community
I compared C type asteroids and comets for this question. C type asteroids have around 30% of empty space, meaning that that much space can be for water.
Comets have around 40% of empty space.
Obviously, just because they have more empty space does not mean they have more water. However, evidence for water on Earth originally comes from comets. Not only that, but comets are occasionally balls of ice with some rock. Asteroids are known for being just rocks, and only have a limited amount of water.
In conclusion, comets are more water rich.
Hope that helps...?
Well, in response to the response of @MystaryPi.
"..However, evidence for water on Earth originally comes from comets.." The above statement is not 100% true, despite that fact that was the common belief how the Earth got its water until the recent Rosetta mission. This question can be partially answered by the ratio between the Deuterium and Hydrogen atoms of observed comets. The D/H isotope ratios of water measured on comet 67P/Churyumov-Gerasimenko by Rosetta and on other comets by other in-situ spacecraft have obtained accurate values, bringing up the prelude to the idea that water on terrestrial oceans may emanate from objects that were of non-cometary nature, simply because those D/H values do not correspond to the D/H values measured on terrestrial oceans. As such, it is thought now that the origin of water-brining objects to Earth to be more asteroid-like, which likely formed much closer to the Sun than the comets.
For more information please refer to Altwegg et al., 2014 (DOI: 10.1126/science.1261952)