= Karel Schrijver Books =

Karel Schrijver is a retired space scientist living in the Portland area. 

== One of Ten Billion Earths, 2018, Oxford University Press ==

Purchased after an Exoplanet lecture at OMSI on November 13, 2018 

 .p078 penultimate paragraph: Eris is a "scattered disk" object.  The [[ https://en.wikipedia.org/wiki/Scattered_disc | scattered disk ]] reaches twice as far as the 50 AU Kuiper belt. 

 .p115 last paragraph: Ceres may be as much as 30% water, "possibly contains a few times as much as all water on Earth combined".  
  . '''''No'''''  [[ https://en.wikipedia.org/wiki/Ceres_(dwarf_planet) | Ceres ]] mass is 9.39e20 kg, 30% of that is 2.8e20 kg .  The mass of the Earth's hydrosphere is [[ https://en.wikipedia.org/wiki/Ocean#Physical_properties | 1.4e18 metric tonnes ]] or 1.4e21 kg.     [[ https://www.scientificamerican.com/article/rare-diamond-confirms-that-earths-mantle-holds-an-oceans-worth-of-water/ | According to this 2014 Scientific American article]], the mantle contains as much water (as mineral hydroxide) as the ocean.  So, Ceres contains less than 10% of the water that the Earth does.  Still, that is a huge amount of water, far more than the surface of Mars or the Moon, at the bottom of a 510 m/s gravity well, and may enable vast asteroid-belt settlement.