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作为最接近太阳的行星,水星在白天灼热难当,而到夜晚则冰冷严寒。如果在水星的日间那一侧着陆,太阳看上去足有从地球上看到的两倍半大,但天空看起来却是黑色的,因为水星上没有任何空气。而地球这颗行星,看起来像是一个大大的淡蓝色发光的“星”。太阳的引力使得水星沿着一个椭圆形的轨道围绕其公转,但这颗行星的自转却异常缓慢。水星的表面坑痕累累,这是因为它曾经被无数颗小行星和彗星撞击过,在其表面甚至还有陨石坑中套着坑,坑内还有坑的景象。
As the planet closest to the Sun, Mercury sever heat during the day and cold and cold at night. If you land on the daytime side of Mercury, the sun looks twice as large as it would have been seen on Earth, but the sky looks dark, because there is no air on Mercury. And the planet Earth, looks like a big light blue glowing “star.” The sun's gravity causes Mercury to revolve around an elliptical orbit, but the planet's rotation is unusually slow. Mercury's surface is full of pit marks because it has been hit by countless asteroids and comets, with craters on its surface and craters in the pit.