Chemistry it is dissolved in water, and a base is one that produces hydroxide ions when dissolved in water. According to Brønsted–Lowry acid-base theory, acids are substances that donate a positive hydrogen ion to another substance in a chemical reaction; by extension, a base is the substance which receives that hydrogen ion. A third common theory is Lewis acid-base theory, which is based on the formation of new chemical bonds. Lewis theory explains that an acid is a substance which is capable of accepting a pair of electrons from another substance during the process of bond formation, while a base is
NASA Star and Exoplanet Database public data to support the search for and characterization of extra-solar planets (exoplanets) and their host stars. The data include published light curves, images, spectra and parameters, and time-series data from surveys that aim to discover transiting exoplanets. All data are validated by the NStED science staff and traced to their sources. NStED is the U.S. data portal for the CoRoT mission. As of December 2011, SDtED is no longer in operation. Most data and services have been transferred to the NASA Exoplanet Archive. Data are searchable either for an individual star or by stellar and planetary properties. NStED offers