Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere,the heat radiates back into space. 白天，那裡的溫度可以達到零上，但因為包裹火星的大氣層極為稀薄，熱量又會輻射回宇宙中。
This afternoon's sunshine could nudge the temperature above freezing. 今天下午的陽光可使溫度達到冰點以上。
On a cloudless night, frost may form on horizontal surfaces even when the temperature of the air is above freezing. 在晴朗的夜晚，即使空氣的溫度在冰點以上，地平面上也能結霜。
