We always have wondered whether or not we are alone in the universe. Mind blowing discovering like hydrogen plumes on Enceladus have given hope to scientists that we may find our neighbours one day.
However in the quest of theirs they have to remember some key points in mind such as the requirements of life. We are carbon based life forms that breathe oxygen and consume water. So logically that is what we must look for.
We all know that some elements are vital for the existence of life as we know it. Carbon is one of them and is the basis of all life on Earth. We are all made of carbon and it’s compounds. However it is not alone. Hydrogen, Oxygen, Nitrogen and Phosphorus are some other elements which are crucial for life on Earth.
Phosphorus is one such element that life depends heavily upon. And if you don’t know is hitting headlines recently. Why? Because of its rarity in the cosmos. This might not be a good sign for alien life.
Two scientists namely Jame Greaves and Phil Sigan were studying material that came out of supernovae, the explosive deaths of massive stars. It is theorised that most of the elements on the periodic table are either synthesised in the core of stars or in supernovae.
These elements are then scattered across the universe by supernovae which then form planets and maybe even support life.
Shockingly what they found was that the supernova explosions lacked phosphorous, a key ingredient for life as we know it. Earth has an abundance of it. But the rarity of this vital element in the cosmos might indicate that life on Earth may have been a fluke or may be very rare in our Universe.
This is called the Rare Earth hypothesis and is one of the many solutions to the Fermi paradox, which asks the question, “If alien life is abundant, why haven’t we met them yet?”
Of course there are many answers to that but the rarity of life on Earth is one of them. However we must not forget that there exist billions upon billions of galaxies in the known Universe and each galaxy hosts a million stars. Most of these stars have planets. Given the sheer number of planets that is, it is seems impossible we are alone.
And there is one more catch. We are looking for life as we know it. What about life as we do not know it?
Science is all about considering all the possibilities. For example life is carbon based because of a special property of carbon called catenation. This property allows it to bond with many other carbon atoms form long chains of hundreds of carbon atoms.
Another element that exhibits this property, though to a much lesser extent is silicon. Thus silicon-based life is a huge topic of debate in astrobiology.
Who knows what is out there. There maybe life that lives in harsh environments. Life forms that are not based off carbon. Maybe they drink liquid methane for living. We can never completely rule out any possibility without a proper scientific base to it.
Thus the phosphorus problem may be a problem for life forms like us but may not be a problem for silicon-based life. Do not panic alien enthusiasts.
As the famous Arthur C Clarke put it, “Two possibilities exist: Either we are alone in the universe or we are not. Both are equally terrifying”