瑞奇·阿诺德：教师和宇航员
NASA astronaut Ricky Arnold takes an out of this world “space-selfie” while conducting a spacewalk on March 29, 2018. Before he joined the Astronaut Corps, Arnold was a teacher, who taught all over the world from Malaysia to Romania. As an astronaut he served on STS-119 and aboard the International Space Station’s Expedition 55/56. #Teacher...