Ceres Bright Spot is Salty -- SkyAndTelescope.com {actually, it's more like washing soda}
By: Camille M. Carlisle | June 30, 2016
Spectral observations by NASA’s Dawn spacecraft reveal that the dwarf planet’s mysterious beacon is made of salt.
Planetary scientists say they’ve finally solved the mystery of Ceres’ bright spot. The spot, a comparatively reflective blotch in the crater Occator, has been a mesmerizing topic of debate for several years now. JPL even ran a public poll asking people what they thought the spot was — with options of volcano, geyser, rock, ice, salt, and “other” — and has had more than 190,000 respondents. As of last month, the two most popular options were ice (about 28%) and other (38%).
Unfortunately for those voters, the winning answer is salt.
Scientists have suspected salts for a while. (Ice can’t survive on Ceres’ surface: it’ll sublimate.) Last December, scientists with NASA’s Dawn mission suggested the bright Occator splash — which isn’t the only one: there are many, lesser bright spots across the dwarf planet — contained magnesium sulfate. But Maria Cristina De Sanctis (National Institute of Astrophysics, Rome) and fellow Dawn scientists report June 29th in Nature that infrared spectral data instead reveal a different salt, sodium carbonate, with some ammonia mixed in.
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more: http://www.skyandtelescope.com/astronomy-news/ceres-bright-spot-is-salty-3006201623/?utm_source=newsletter&utm_campaign=sky-mya-nl-160701&utm_content=859424_SKY_HP_eNL_160701&utm_medium=email
On earth, the mineral form of sodium carbonate is known as natron, and was used by ancient Egyptians in the mummification process. It's commonly found (together with trona) in alkaline flats formed by evaporation of ancient lakes, and in current alkaline lakes, particularly those replenished by thermal springs. The chemical itself is commonly known as soda ash.
