Christina hammock koch[1] (/ kʊk / cook; Born january 29, 1979) is an american engineer and nasa astronaut of the class of 2013. [2][3] she received bachelor of science degrees.

Since the beginning of her career, christina aguilera's voice has been one of the most distinctive in pop, thanks to her out-of-this-world range and wise-beyond-her-years lyrical interpretations. Christina maría aguilera (born december 18, 1980) is an american singer, songwriter, record producer, actress and dancer. Aguilera is known for her strong voice, which can reach high notes, and for. In 1999 she had her breakthrough hit, genie in a bottle. since then she's made millions of fans, sold millions of records, and won many awards, including a grammy for best new female artist.