2012年商务英语考试媒体英语词汇（17）
Background: 科学杂志《自然》上的一项新的研究报告认为地球可能曾经拥两个月亮，不过在天体碰撞后，比较小的一个消失了。科研人员认为，碰撞过程可能相当缓慢导致月球上出现了鲜为人见的凹凸不平的高地结构。中 华 考 试 网
This new theory builds on the idea that around four billion years ago the Earth was struck by a Mars-like planet, but instead of the smash producing enough debris for one moon, this paper argues there was enough for two.
This small second moon became stuck in a gravitational tug of war between the Earth and its much larger sibling. After millions of years in this position the new moon was drawn into a collision at a speed of less than three kilometres per second.
The scientists say this slow paced crash may have caused a build up of material and the formation of highlands on the Moon's far side.
For decades scientists have been trying to understand why the visible near side of the Moon is covered in craters while the far side has mountain ranges higher than 3,000 metres.
The researchers hope that Nasa observational missions might prove this new theory within a year.
小编推荐：
下一篇：商务英语常用缩略词:I
一级建造师二级建造师二级建造师造价工程师土建职称公路检测工程师建筑八大员注册建筑师二级造价师监理工程师咨询工程师房地产估价师 城乡规划师结构工程师岩土工程师安全工程师设备监理师环境影响评价土地登记代理公路造价师公路监理师化工工程师暖通工程师给排水工程师计量工程师
执业药师执业医师卫生资格考试卫生高级职称执业护士初级护师主管护师住院医师临床执业医师临床助理医师中医执业医师中医助理医师中西医医师中西医助理口腔执业医师口腔助理医师公共卫生医师公卫助理医师实践技能内科主治医师外科主治医师中医内科主治儿科主治医师妇产科医师西药士/师中药士/师临床检验技师临床医学理论中医理论
