英语翻译Many scientists today are convinced that life exists elsewhere in the universe—life probably much like that on our own planet.They reason in the following way.As far as astronomers can determine,the entire universe is built of the same

英语翻译Many scientists today are convinced that life exists elsewhere in the universe—life probably much like that on our own planet.They reason in the following way.As far as astronomers can determine,the entire universe is built of the same
英语翻译
Many scientists today are convinced that life exists elsewhere in the universe—life probably much like that on our own planet.They reason in the following way.
As far as astronomers can determine,the entire universe is built of the same matter.They have no reason to doubt that matter obeys the same laws in every part of the universe.Therefore,it is reasonable to guess that other stars,with their own planets,were born in the same way as our own solar system.What we know of life on earth suggests that life will arise wherever the proper conditions exist.
Life requires the right amount and kind of atmosphere.This eliminates all those planets in the universe that are not about the same size and weight as the earth.A smaller planet would lose its atmosphere,a larger one would hold too much of it.
Life also required a steady supply of heat and light.This eliminates double stars,or stars that flare up suddenly.Only single stars that are steady sources of heat and light like our sun would qualify.
Finally,life could evolve only if the planet is just the right distance from its sun.With a weaker sun than our own,the planet would have to be closer to it.With a stronger sun,it would have to be farther away.
If we suppose that every star in the universe has a family of planets,then how many planets might support life?First,eliminate those stars that are not like our sun.Next,eliminate most of their planets,they are either too far from or too close to their suns.

英语翻译Many scientists today are convinced that life exists elsewhere in the universe—life probably much like that on our own planet.They reason in the following way.As far as astronomers can determine,the entire universe is built of the same
许多科学家今天确信生命存在于宇宙的其他地方,生命的存在环境可能与我们生存的地球极为相像,理由如下：
就像天文学家能够确定的那样,宇宙全部是由相同的物质组成.他们不怀疑在宇宙的任何地方物质都遵从相同的法则.因此,有理由相信其他的星球,也像我们人类生存的地球一样伴随着她的卫星诞生在太阳系.地球上生命的存在这一现象已经告诉我们,生命诞生于适宜生存的环境.生命需要正确的量变和适宜的生存空间,这就排除了在宇宙中许多与地球质量与大小不相类似的星球.小的星球可能没有它自己的大气层,而大的星球可能有拥有更多的大气层.
生命也需要一定数量的能量和光照,这就排除了双体恒星,或者由能量燃烧后形成坍塌星球,因此,只有像我们太阳那样提供恒定的光照和能量那一类的星球,我们才可以确定它们为生命提供了存在的前提条件.
最后,生命的存在也取决于它所在星球与太阳（或理解为能量星球）之间的距离,如果能量星球光照弱,那么生命体所在星球就近,反之,则远.
如果,我们假设每一个星球都存在于一个星系中,那么有多少星球可能存在生命呢?首先,排除那些在没有像太阳一样提供能量的星系中星球,其次,再排除那些与能量星球太远或太近的星球.