Platinum, iridium and the rest are expensive precisely because they are rare.

正因为稀有，铂、铱等矿物才价格不菲。

If I run the hydrazine over an iridium catalyst, it'll separate into N2 and H2.

假如我用铱催化剂解联氨，解成氮气和氢气。

I'm going to delete " cretaceous, " I'm going to delete " Cenozoic" and I'm going to delete " iridium."

我要删除“白垩纪”、“新生代”、“铱”。

The metre was the distance between two scratches on a bar composed of a special alloy of platinum and iridium.

1米是指一根铂铱特殊合金杆两端划痕间的距离。

Iridium...What do they need the iridium for? -It's a stabilising agent.

铱...他们要铱干什么？-用来做稳定剂。

Yeah, iridium. It's found in meteorites. It forms anti-protons.

是的，金属铱。这种西是从陨石中发现的。可以形成反质子。

Iridium is an element that’s rare on Earth, but very common in asteroids and comets.

铱是地球上稀有的元素， 但在小行星和彗星中却很常见。

The earth has Iridium in it, but because it is a heavy metal, most of it settles towards the center of the planet.

地球也有铱，但因为是重金属，多数都沉降到行星的中心。

It's about 65 million years old and contains a lot of iridium, an element that's usually rare on Earth's surface.

约有 6500 万年的历史，含有的铱，这种元素在地球表面通常很稀有。

Iraq reported the theft of up to 10 grams of iridium isotope used to treat cancer to the International Atomic Energy Agency late last year.

伊拉克报道称去年年底报道称国际原子能机构用来治疗癌症的铱同位素丢失了10克。

There must have been a long time, between the impact below the core and the arrival of the Iridium at the top.

所以岩芯下的碰撞坑和顶部的铱元素层必然间隔了很长一段时间。

A hunk of platinum and iridium known as the International Prototype Kilogram or IPK. The IPK isn't just how much a kilogram weighs.

一块铂和铱，称为国际原型千克或 IPK。 IPK 不仅仅是一公斤的重。

Indeed, the discovery of a layer of iridium-rich rock (iridium being one of platinum's relatives) was the first sign geologists found of the asteroid impact that is believed to have killed the dinosaurs.

实际上，地质学家们提出小行星曾撞击地球的第一个证据就是发现了富含铱的岩层（铱是铂的同族元素之一）。人们认为恐龙就是因小行星撞击地球而灭绝的。

Among these is the element iridium, which is a thousand times more abundant in space than in the Earth's crust (because, it is thought, most of the iridium on Earth sank to the core when the planet was young).

其中有元素铱。这种元素在太空里要比在地壳里丰富100倍(据认为，这是因为部铱在地球形成之初已经沉入地心)。

And um, anything else that looks like it may not appear, " iridium" is an element, probably not going to get that on the test, so I am going to delete it, that's I don't want to waste my time studying that.

其他任何看起来可能不会出现的西，“铱”是一种元素，可能不会出现在考试中，所以我要删除，因为我不想浪费时间研究。