Eros is one of the planetoids which passes near the earth every now and then . 爱神星是一个时常靠近地球的小行星。
2.
There is a maximum size that mountains can attain that gets smaller as the planetoid gets more massive （山体能达到的高度是有限度的，而且小行星引力越大，山体能达到的高度就越低。 ）
3.
Solar system ' s main member includes : sun ( star ) , nine planets ( including earth ) , innumerable planetoids , multitudinous satellite ( including moon ) , but also has the comet , the meteor as well as the massive dust matter and the thin gaseous state matter 太阳系的主要成员有：太阳（恒星） 、九大行星（包括地球） 、无数小行星、众多卫星（包括月亮） ，还有彗星、流星以及大量尘埃物质和稀薄的气态物质。
