Wonders of the Universe - Brian Cox [42]
When looking at a spectrum of light from our sun you can see hundreds of Fraunhofer lines, and each and every one of those corresponds to a different element in the solar atmosphere which absorbs light as it passes through. From sodium in the yellow, through iron, magnesium, and all the way across to the so-called hydrogen alpha line in the red, the signatures of each of the elements are encrypted in the solar code.
So by looking at these lines in precise detail you can work out exactly which elements are present in the Sun. This turns out to be roughly 70 per cent hydrogen, 28 per cent helium, and the remaining 2 per cent is made up of the other elements.
It is worth repeating here that you can apply this theory not only to the Sun, but for any of the stars you can see in the sky – which allows us to measure the constituents of their atmospheres with extraordinary accuracy. Isn’t it simply wonderful that just by looking at the light from those twinkling stars we can tell what those fiery worlds, so far away, are made of?
These spectrographic investigations of the light from the cosmos have confirmed what our scientific intuition suggested to us: wherever we look, we only ever see the signatures of the set of ninety-four naturally occurring elements that we have collected and identified here on Earth.
So it is clear that we are connected in a very real sense to the whole of the Universe – with its hundreds of billions of stars across billions of galaxies – because we are all intrinsically made of the same stuff. And, as we will explain, there is one very simple reason for that: everything in the Universe shares the same origin
THE EARLY UNIVERSE
In order to understand where we come from we have to understand events that happened in the first few seconds of the life of the Universe. When the Universe began it was unimaginably hot and dense – we literally don’t have the scientific language to describe it. It was beautiful in a very real sense. There was no structure, there was certainly no matter, and it was exactly the same whichever way you looked at it. It’s a difficult concept to grasp, but we can get some idea of what happened to the early Universe by looking at the behaviour of one of the most common substances on Earth: water.
Water is one of the most common substances on Earth, but it can produce some of the most spectacular geological wonders on our planet. The El Tatio Geysers in Chile are just one example of water’s awesome activity.
© Charles O’Rear/CORBIS
One of Earth’s most incredible natural wonders, the El Tatio Geysers make up the largest geyser field in the world. As they are located at a height of 4,200 metres (13,800 feet) in the Chilean Andes, they are also the highest.
EL TATIO GEYSERS, CHILE
High in the Andes Mountains, in the far north of Chile, you will find the spectacular El Tatio Geysers. Erupting at 4,200 metres (13,800 feet) above sea level, this is one of the geological wonders of Earth’s Southern Hemisphere. Not only is it one of the largest geyser fields in the world, it is also one of the highest. For those who journey here to witness the eruption of the jets of water skywards there is only one time to visit – sunrise.
In the early morning, as the Sun begins to peer over the horizon, the combination of super-heated water and freezing cold air produces a rare phenomenon. Like all geysers, the boiling water delivered to the surface by the geological plumbing bursts out and flashes into steam, forming the majestic columns. But here, because of the high altitude