Hernandez, who considers Stockton, Calif., his hometown, grew up in a migrant farming family, traveling each year between Mexico and California. He did not learn English until the age of 12.
"I was inspired to pursue a dream to one day work in space while listening to the radio news about space exploration while working in the fields of northern California," Hernandez said. "I hope to spread that excitement about space, science and engineering and inspire others to follow their dreams by sharing my activities and interacting with my followers on Twitter."
His tweets are available at http://www.twitter.com/astro_jose