据说,这是世界上最后两趟窄轨蒸汽小火车,它们因时代的进步而隐秘在丛山峻岭中,又阴差阳错的成为当地的生命线,而行驶至今,古老的机器仍在改变着一群人的生活,它们成为一段传奇。。NASA's Jet Propulsion Laboratory to follow the birth of the Perseverance rover, whose primary mission is to search for traces of life in an ancient river delta on Mars and collect samples for eventual return to Earth.。