In our last post we took a glimpse at auroras in the making – a spectacular light show staged not by a Roman deity sadly, but by the solar wind. Today we will see where this solar wind originates from (the Sun, unsurprisingly) and see how the draughts of the stars yield the lights of the skies.
Last week we walked through the gallery of the universe to observe the majestic broad strokes found strewn across the canvas of interstellar space. This week we’re going to wander slightly closer to home, and take a look at the beautiful natural lights put on for us by our very own skies. However, they do get a little bit of help from a certain life-giving star, not to mention a lot of physics…
We begin our journey at the advent of the Stone Age. Human-like species, or hominids, aren’t able to run as fast as their prey, nor do they stand an earthly chance of surviving brawls with other predators. They can, however, yield a much more powerful weapon – their intelligence. They learn to utilise stone tools in order to gain a technological advantage, and they learn to yield stone weapons in order to exercise their superiority over other species. Here commences the birth of civilisation.
Fast-forward three and a half million years and we arrive at the Bronze Age. The Bronze Age is considered to have begun during the fourth millennium BC with the onset of the production of bronze – an alloy consisting of a copper majority with a supplement of tin. By combining the attributes of two metals, the homo sapiens concocts a metal with strength and durability unmatched by any other material at the time. Stone certainly cannot contend.
Fast-forward another mere three millennia and we arrive at the Iron Age. The Iron Age is considered to have begun during the early first millennium BC and to have ended by the Middle Ages. Iron, although simpler in structure than bronze, is a more difficult metal to extract from its ore. Nonetheless, the reward is immense. The discovery of steel, one of the strongest common materials on the planet, provides human civilisation with another rung in technological advancement.
This is the three-age system. Some say that we currently live in a fourth age – the Silicon Age. Nowadays we can scarcely step in any direction without being in close proximity to a silicon transistor – an essential component of every electronic circuit and which exists in masses of a few billions at a time in a smartphone.
Silicon extends its range of applications to photovoltaic technology. Silicon is by far the most prevalent material in solar cells, the building blocks of solar panels. However, a newer material, perovskite, has captivated the interest of many researchers in the field of semiconductor electronics. Its promisingly high efficiency could put an end to the days of silicon solar cells. For solar cells, could this be the start of the Perovskite Age?
We, as living creatures, rely upon the well-being of planet Earth for our own survival. A quick glance at the news and one will notice that we’re not doing such a great job at keeping ol’ Mother Nature healthy. Global warming this, pollution that – we’re not very good guests, are we? I say this, but it’s actually very difficult for our bustling, resource-reliant society to function without the things that do harm to the environment. Our only hope is to constantly be on the lookout for more efficient, cleaner methods that we will be able to sustain into the future. And, as always, science is the way forwards.