science

Behind the Auroras

The Aurora Borealis & Aurora Australis are both beautiful light shows as well as visual signs that the Earth’s magnetosphere is still protecting us from a constant barrage of destructive particles from the Sun.

The lights

In mythology & folklore the Northern Lights have been seen as both good and ill omens. This tended to depend on your degree of latitude which dictated how frequently you saw them. Northern people more accustomed to the lights such as those of Sweden, Norway, and Finland saw the lights as the energies of the departed and worthy of respect. Similarly, different peoples of Alaska saw the lights as the dancing spirits of humans or animals. Further south in ancient Rome, where the lights were seen less frequently, they were seen as a harbinger of war or famine.

Scientifically, the aurora are the result of charged particles from the sun (protons & electrons) interacting with oxygen & nitrogen in the Earth’s atmosphere. The different colors are the result of which gases the particles encounter at which altitudes. The most common color is yellow-green which is the sun’s particles interacting with oxygen at around 60 miles above the Earth. Nitrogen produces blue light below 60 miles in altitude but produces purple light above that. Red is also produced by oxygen but at altitudes above 150 miles. The light produced in these exchanges lasts only a second or less but the steady stream of particles from the sun can create long lasting light shows.

The aurora are the reaction of protons & electrons from the sun interacting with gases in our atmosphere.

Special Delivery

The sun is constantly emitting these charged particles. The solar wind regularly delivers a steady stream of particles to Earth but they are also unleashed in larger more powerful bursts through solar flares and coronal mass ejections (CMEs). When any of these charged particles approach Earth their path is directed by the Earth’s magnetosphere which is essentially a magnetic force-field generated by the Earth. The magnetosphere deflects most of these particles around & away from the Earth, however some particles are pulled down towards the magnetic northern and southern poles. It’s these particles pulled towards the poles that create the dazzling auroras.

Earth’s magnetosphere directs the sun’s particles towards the poles. It’s also what keeps us alive.

The Earth’s magnetosphere acts a shield, deflecting & directing particles from the sun.

So where is the danger?

The key to the aurora light shows, and our survival, is the magnetosphere. Without it, Earth would be subjected to the full brunt of the emissions from the sun. If left completely exposed these charged particles would gradually strip the Earth of its atmosphere. No atmosphere, no life. It has been theorized that Mars once had a magnetosphere but lost it approximately 4 billion years ago. As a result the atmosphere was carried off into space by the solar wind. With no atmosphere the water of Mars boiled off leaving Mars a barren wasteland.

So the light shows of the auroras are the direct result of the constant defensive protection of the Earth’s magnetosphere. This shield protects all life on Earth from the never-ending stream of charged particles that would otherwise end life on Earth as we know it.

Oil’s Origins

Oil doesn’t come from dinosaurs, it comes from plankton.

When people hear “fossil fuels” they sometimes think that oil (petroleum) came from dinosaur fossils. This isn’t out of left field. At the Chicago World’s Fair of 1933-34 Sinclair Oil sponsored an exhibit that taught people that oil was formed during the time of the dinosaurs. Reinforcing this idea there’s also the logo & mascot for Sinclair Oil, Dino the dinosaur. Sinclair again pushed this connection of dinosaurs & oil at the New York World’s Fair in 1964 even though the science had become pretty clear that oil wasn’t made from dinosaurs. So what makes oil? Plankton.

What are plankton?

Plankton are water dwelling life forms that (more or less) drift with the current. The name “plankton” actually comes from the Greek for “wanderer” or “drifter” which makes them sound like edgy antiheroes in a pulp novel. There are lots of different kinds and sizes of plankton, and they fill all sorts of ecological roles ranging from being food for larger organisms to producing 50% of the Earth’s oxygen. Bacterial plankton formed in the oceans 3 billion years ago and were basically the only form of life until 600 million years ago. That’s an enormous amount of time. So as plankton over that time died, most fell to the bottom of the sea floor and began the process of becoming oil.

Let’s make oil

Lots can happen during hundreds of millions of years. The plankton that fell to the bottom of the oceans continued to accumulate as well as other sediment. The plankton would decompose releasing most of their chemicals but the hydrogen & carbon would remain. This continuous process of plankton and other sediment falling to the ocean floor meant that the former material would be pushed further down and compacted under intense pressure over millions of years, generating heat. It was this pressure and heat that “cooked” all of those plankton into oil.

While it is certainly possible that some dinosaurs may have found themselves a part of this oil making process, it’s just very unlikely they made up much oil – they usually weren’t in the right places and there weren’t enough dinosaurs (not enough raw material to cook with). Instead of being made from some of the Earth’s largest creatures, oil was made from massive amounts of some of the smallest.