We are like passengers on board, travelling through the universe on earth. While most of us care little about the rest of our ship apart from our own cabins.                                                                        --S.P.Langley

Imagine a world in which very small amount of material is as heavy as Mount Everest (珠穆朗玛峰).The gravity of the celestial body's（天体） surface is so strong that a human visitor would be squeezed into a pie thinner than a atomic nucleus by his or her own weight.

Now imagine a star is torn by a bizarre gravitational funnel（漏斗） to gas tendril (气体卷须) . At that time, the sky of  the planet orbiting the star would be lighten by the light produced by that process. This area would not exist any creature alive because of the X-rays more than a fatal dose.

Imagine a planet hidden beneath a dense carbon dioxide atmosphere with  Sulfuric acid rain. Temperature here is astonishing high. Lead ( 铅) whose melting point is 328 Degrees Celsius would become liquid as that of a thermometer. In such a hell-like environment, human explorers would die of high temperature and asphyxia (窒息) .

Next, imagine there are two stars in one area.  In the strong gravitational effect, they are like dancing Waltz while millions of tons of gas matters are flowing between them. This tug of war (拉锯战) would be ended by one star's destruction by its explosion which would no doubt burns every single planet nearby.

All these scenes above do exist. That dense celestial body with super strong gravity is the core collapsed from an explosing star, called neutron star. The gravitational funnel is a massive black hole which is believe to be the central of our galaxy. That carbon dioxide greenhouse is Venus(金星) , the nearest planet of earth , which is the brightest celestial body in the night sky preceded only by（仅次于） the moon. The binary system（双星系统） is Lyra β（天琴座β） which is available  in the midsummer night. In a universe with hundreds of thousands of billions of billions of stars and ten thousands of billions of unknow planets, any attempt to comprehend of all diversities of universe is in vain.

For me, when I stand under the firmament（苍穹） decorated by stars, I always feel the endless charm of the universe and realise with fear that our earth is just one dust floating in the cosmos. Although our thoughts of our position in the cosmos makes the dust less ordinary, our curiosity of aliens makes the distanced celestial bodies more mysterious.