lthough we have never been able to reach Earth’s core due to its extreme temperature, we have been able to identify the different layers of our Planet and consider that in the middle we have the core which sustains Earth. For many years people have speculated that maybe something else is hidden within our Earth’s core, some theories say there lives a secret civilization that rules us all, but researchers from the Australian National University have found evidence of a secret structure within Earth’s core.
Earth’s not-so-simple core
School books teach us that our Earth is comprised of 4 specific layers which all play an important part in sustaining our planet’s ecosystem. The 4 different layers are:
- The Crust is represented from the surface to 70km (43 miles) in-depth and with a temperature of around 200 to 400 degrees Celcius (400 to 750 Fahrenheit).
- The Mantle is represented from the bottom of the crust to 2,900 Km (1,800 miles) in-depth and with a temperature of around 4,000 degrees Celcius (7,230 Fahrenheit).
- The Outer Core is represented from the bottom of the Mantle to 2,300 Km (1,400 Miles) in-depth and with a temperature of 4,000 degrees Celcius (7,230 Fahrenheit) at the top. Near the bottom, the temperature can reach 5,000 degrees Celcius.
- The Inner Core is represented from the bottom of the Outer core to 1,220 Km (750 Miles) in-depth and with a temperature of around 5,400 degrees Celcius (9,800 Fahrenheit).
Pretty simply right? What if I told you that there is a fifth layer within the Inner Core. The research was done by The Australian National University led by Ph.D. researcher Joanne Stephenson. The research consisted of running the dataset of about 100,000 earthquake waves through a very complex algorithm that would try to find the best scientific explanation to justify the data.
A Core inside the Core?
Each Earthquake wave changes the speed at which it travels based on the different layers it passes but maintains a similar angle. What the algorithm presented is that when the earthquake wave would reach the center of the inner core, the angle would not be parallel anymore with the equator, shifting at an angle of 54 degrees. Also, some of the waves were passing way more quicker than others.
This means that there is something within the Inner Core to which the authors of the paper are referring as the “inner-inner core” with a radius of 650 Km (400 Miles). This could actually explain why the different Ice Ages have taken place throughout history.
“We found evidence that may indicate a change in the structure of iron, which suggests perhaps two separate cooling events in Earth’s history,” (Quote by Joanne Stephenson)
Now we know for sure something is there, but we don’t know what exactly could be there. It is amazing to see how our knowledge of what is inside the Earth had changed. In 1936 a paper was written by Dr. Inge Lehmann who was the first to theorize that the Earth has two separate layers. After almost 30 years of research(1970), she had confirmed that there are actually 4 layers (the ones represented above).
Such a huge discovery will have exponential changes not only in the world of science but the way we see our world and most importantly, all textbooks are rewritten to represent the fifth layer of our Planet. This could also include some history textbooks once we identify more data about this fifth layer and the possible implications it could have had with cooling events from the past.
Is our Planet Expanding?
Right now, Dr. Joanne Stephenson and her team are working with mineral physicists and geodynamics from around the world to produce a model of what the inner-inner core is composed of or what it may actually be. An interesting theory that Dr. Stephenson offers is that this inner-inner core wasn’t here about 100 years ago, this may be a possibility of our Earth Slowly expanding. As the planet cools down, the inner core also cools making the iron from which it is made crystallize, therefore expand.
I will definitely keep up to date with this research and publish an article once a paper comes up with some interesting findings. Nevertheless, as insignificant as it may sound, this discovery is a great milestone within the world of science and I can’t wait to see how this will help us describe ancient historical events such as major volcanic eruptions or even Medieval Global Warming.