Today, Joel's team
今天乔尔的团队
are testing the wheels of Curiosity's twin.
要测试好奇号复制品的车轮
They're low class.
它们是低级的
Is that what we call them?
我们就这样叫它们吗
That's what we call them.
没错 就这样叫
It's just one of hundreds of tests
过去九个月中
the rover has been through
火星车经历了上百种测试
in the past nine months.
这只是其中一项
That's great.
不错
The scientists want to land on Mars and explore.
科学家想要在火星着陆并进行探索
They want to explore where we land
他们想要探索降落点
and then also explore kilometres away from where we land,
然后再探索数公里外的区域
and that means we have to drive.
这意味着火星车必须能移动
We'd like to be able to drive over big rocks
我们希望它能够跨过大石头
so that we can drive close to a straight line,
那样就能直线行驶
not too much meandering around,
不需要绕远
and therefore we designed a big rover.
因此我们设计了一个大型火星车
That makes it tricky.
这也令它变得棘手
The reason Curiosity is so big and expensive
好奇号体型巨大且价格昂贵的原因在于
is because of the science it will be conducting on Mars.
它将在火星上进行的科学研究
It will have to drive across difficult terrain
它必须搭载满是仪器的小型实验室
while carrying a lab full of equipment.
穿过崎岖的地形
The scientists would like an infinitely capable vehicle.
科学家希望拥有一辆全能的交通工具
But in the real world,
但在现实中
the machine has to fit within a certain volume.
这个机器必须小于一定的体积
It has to fit within a certain mass.
以及小于一定的质量

重点解释：

1.hundreds of 许许多多的

例句：There were hundreds of slaves in the plantation.
这个种植园里有数百名奴隶。

2.away from 远离, 从某地离开

例句：The poor man ran away from his creditors.
这个穷人躲避他的债主。

3.be able to 会； 能

例句：You'll be able to come, won't you?
你能来的，对吗?