这家直销公司通过会员制度销售健康产品。

This ___DSO sells health products through a membership system.

天文学家发现了一个新的深空天体，距离地球约500光年。

Astronomers discovered a new ___DSO about 500 light-years away from Earth.

这个数字存储示波器可以捕获高频信号。

This ___DSO can capture high-frequency signals.