These disks are the remnants of planetary formation.

这些圆盘是行形成的剩余物质.

According to planetary formation models, that wasn't possible!

根据行形成的模型，这是不可能的！

Should Mercury be stripped of its planetary status?

那么水被剥夺其行地位吗？

It's going to some other planetary system.

而是去了其它系。

That's a very common shape for planetary nebulae.

这是行状云很常见的形状。

Only one planetary defense method has been tried against an asteroid.

目前只有一种行防御方法被尝试用来抵御小行。

The Smithsonian Institution says they were the first ever retrieved from another planetary body.

史密尼学会天文台说，这是有史以来第一次从另一个行体中找到它们。

So some planetary systems are aligned just so.

所以有些行系就是这样排列的。

Jay Melosh studies planetary impacts at Purdue University.

在普渡大学研究行撞击的杰伊·梅洛什说到。

Bruce Betts is chief scientist for the nonprofit Planetary Society.

布鲁·是非营利组织“行协会”的首席科学家。

Richard Moissl is head of the European Space Agency's (ESA) planetary defense office.

理查德·莫伊塞尔是欧洲航天局（ESA）行防御办公室负责人。

Mercury brushes against another planetary embryo.

水与另一颗胚胎期行擦肩而过。

This explosive planetary drama demands a dynamic human response.

这场爆炸性的地球戏剧需要人类作出积极的反。

The other, a planetary carcass gouged by millions of high velocity impacts.

另一个，一片死寂形成于大量碰撞。

So planetary astronomer, Heidi Hammel, submits a proposal to NASA.

行天文学家海蒂∙海莫向NASA递交了一项建议。

The timing issue has everything to do with planetary mechanics.

这一时间安排与行力学有很大关系。

Or is the planetary model of the atom doubly wrong?

或是行原子模型又错了?

The planetary safety boundary of 1.5 degrees has not been reached.

地球还没有达到1.5度的安全界限。

The rockets will be used to study physics and planetary science.

这些火箭将用于研究物理学和行科学。

And we see all the stars surrounded by completed planetary systems.

我们也知道所有恒都由完全形成的行系统环绕。