The largest asteroid is Ceres, which is about a quarter the size of the moon.

最大的小行星是谷神星，其体积大约是月球的四分之一。

《柯林斯英汉双解大词典》

It will probably be easier to do this on the moon than on an asteroid.

显然，在月球上完成这个任务比在小行星上完成要容易。

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Sans wheels, which were needed for last year’s simulations to the surface of the moon, the vehicle could be transformed for asteroid exploration by mounting it on a flying platform, says NASA.

美宇航局说，这个太空探索车是去年月球表面太空模拟的必备工具。 这一工具可以改造一下，安装在一个飞行平台来适应小行星探索。

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Flying in formation, they could map the gravitational field of an asteroid or moon by monitoring tiny changes in their relative positions.

ECONOMIST: Picosatellites

Every planet, asteroid, moon, mountain and crater has its name.

ECONOMIST: Time to start giving extrasolar planets proper names

Advances here will inform the more scifi-ish imponderables like a space elevator, and asteroid- or moon-mining.

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