More expeditions arrive.
（登陆火星）进行了更多探险。
Huge solar mirrors are put in orbit round Mars to heat the polar ice caps.
巨大的太阳反射镜被射入火星的轨道来给两级冰冠热量。
The ice caps are sprayed black, so that they do not reflect the heat away.
冰冠呈黑色雾状，这样就不会将热量反射掉。
Chemicals are released into the air.
化学物质释放到空气中。
As a result, the atmosphere becomes thicker and retains more of the Sun's heat.
结果，空气变得越来越厚，保留了更多的太阳热量。
If the greenhouse effect can be started, the ice caps will melt, releasing water vapour, and the temperature will rise to -40℃.
如果温室效应能够发生，冰冠就会融化，同时释放出水蒸气，温度将升高到零下40摄氏度。
Stage 3 (AD 2095-2130)
第三阶段（公元2095年－2130年）
Next, plants are introduced from Earth.
接下来，植物从地球中被引进。
If these plants can survive on Mars, carbon dioxide can be converted into oxygen.
如果这些植物能在火星上存活，二氧化碳就可以被转化为氧气。
The first clouds appear, and the sky slowly turns from pink to blue.
第一片云出现了，天空慢慢由粉红色变成蓝色。
The temperature goes up to -15℃.
气温上升到零下15摄氏度。
Stage 4 (AD 2130-2145)
第四阶段（公元2130年－2145年）
The warming continues, melting more ice. Rivers and small oceans are made.
温度继续上升，融化更多的冰。形成了很多河流和小海洋。
More people migrate from Earth and construct towns.
更多的人从地球上移居来此，建设城镇。
Forests of trees are planted.
人们种植很多树木。
Mars is looking greener. The temperature is 0℃.
火星看起来越来越绿。温度是零度。
Stage 5 (AD 2145-2185)
第五阶段（公元2145年－2185年）
Mars is getting more like Earth.
火星变得越来越像地球。
The amount of oxygen in the air rises, and the air becomes breathable.
空气中的氧气含量上升，空气随之变得可以呼吸。
The inhabitants can go outside without spacesuits.
居住者能够不穿太空服去外面。
The temperature reaches 10℃.
温度达到10摄氏度。
(Since Mars is 228 million kilometres from the Sun, it can never be as warm as Earth.)
（因为火星距离太阳2亿2千8百万公里，它就永远不可能和地球一样温暖。）
Cities, farms and industries are built all over Mars. The transformation is complete.
城市，农场和工厂在火星各个地方耸立而起。改造完成了。