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

史密森尼学会天文台说，这是有史以来第一次从另一个行星体中找到它们。

These disks are the remnants of planetary formation.

这些圆盘是行星形成的剩余物质.

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

根据行星形成的模型，这是不可能的！

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

另一个，一形成于大量碰撞。

That's a very common shape for planetary nebulae.

这是行星状星云很常见的形状。

Should Mercury be stripped of its planetary status?

那么水星应该被剥夺其行星地位吗？

It's going to some other planetary system.

是去了其它星系。

We who cannot even put our own planetary home in order.

我们，尚不能整治自己的星球的我们。

By the time we're ready to settle even the nearest other planetary systems.

到那时，我们准备好移民到即使是最近的星球的时候。

And from there, be able to map out a timeline of planetary development.

接着我们就能描绘出行星演变的整个过程。

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

我们也知道所有恒星都由完全形成的行星系统环绕。

The mission which launched months ago has been called humanity's first test of planetary defense.

几个月前发射的这一任务被称为人类对行星防御的第一次测试。

And so, this was NASA's first ever planetary defense test mission.

这是NASA的第一次行星防御测试任务。

So some planetary systems are aligned just so.

所以有些行星系就是这样排列的。

However, most planetary scientists still do, which is why we're using that terminology here.

但是，绝大部分行星科学家还是认为冥王星是行星，这就是我们使用这个术语的原因。

Jay Melosh studies planetary impacts at Purdue University.

在普渡大学研究行星撞击的杰伊·梅洛什说到。

We have found so many different kinds of planetary systems in the galaxy.

我们在这个星系中发现了很多不同种类的行星系统。

Mann added that he believes this pattern " is connected to human-caused planetary warming" .

曼恩补充说，他相信这种模式" 与人类造成的地球变暖有关" 。

That planetary heat causes all of this chaotic change, which we could call climate change.

行星的热量导致了所有这些混乱的变化，我们可以称之为气候变化。

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

行星天文学家海蒂∙海莫向NASA递交了一项建议。