 In early 2014 , using data from the Herschel Space Observatory , it was discovered that there are several localized ( not more than 60 km in diameter ) mid @-@ latitude sources of water vapor on Ceres , which each give off approximately <unk> molecules ( or 3 kg ) of water per second . Two potential source regions , designated Piazzi ( 123 ° E , 21 ° N ) and Region A ( 231 ° E , 23 ° N ) , have been visualized in the near infrared as dark areas ( Region A also has a bright center ) by the W. M. Keck Observatory . Possible mechanisms for the vapor release are sublimation from approximately 0 @.@ 6 km2 of exposed surface ice , or <unk> eruptions resulting from <unk> internal heat or from <unk> of a subsurface ocean due to growth of an <unk> layer of ice . Surface sublimation would be expected to be lower when Ceres is farther from the Sun in its orbit , whereas internally powered emissions should not be affected by its orbital position . The limited data available are more consistent with <unk> @-@ style sublimation . 
