Is it, for instance, mostly rock and ice with a few pockets of gas, or is it a loose pile of rubble held together by gravity?
例如，是由大量的石头、冰川和少量的气体构成还是由在重力作用下聚在一起的松散的碎石堆构成。
2
Anchoring to the surface will probably be necessary, but asteroids are made up of different materials - some solid metal, some piles of rubble and some, a combination of rock, pebbles and dust.