While many of us have been led to believe that the atmosphere is a protective bubble keeping things both in and out of earth, according to experts that’s not exactly the case.
Technically, a bubble is something with a reasonably clear edge which is not the case when it comes to the earth’s atmosphere.
The atmosphere actually becomes thinner as you travel further through it until at around 10,000km above earth – it begins to blend with space. This means that things can get in and that they can get out.
One element in particular regularly exits the earth atmosphere, and that element is helium.
To better understand how this all works, let’s travel back to the beginning of time.
“After the Earth formed 4.5 billion years ago, volcanoes spewed a bunch of gasses like methane, carbon dioxide, and sulfur above the planet, and Earth’s gravity kept them hanging around,” Cosmos Magazine Journalist Ellen Phiddian said.
“Earth marinated in this carbony soup for another two billion years, during which it formed life.”
Should we care about the finite supply of helium?
According to Ellen, this is when an event called the Great Oxygen Nation occurred.
“Little organisms called Cyanobacteria started belching oxygen into the atmosphere as a byproduct of their CO2 consumption, and oxygen levels started to increase,” she said.
“For the next couple of billion years, oxygen levels were mostly on the rise until they got to a maximum about 300 million years ago.”
This is when fires and other natural events that consumed oxygen at a rapid rate began to occur and oxygen levels began to drop to our current level. As this was happening nitrogen gas was also leaking out of the earth’s crust along with a gas called Argon.
While Argon, nitrogen and oxygen account for a majority of the earth’s gases, 0.05 percent is made up of other elements including carbon dioxide, hydrogen and helium.
Experts believe that because these gases can exit and enter the earth’s atmosphere at different speeds, helium could be shorter supply.
Cosmos Magazine journalist Ellen Phiddian explores the chemistry of gases, revealing whether we can turn air into food and whether the world could be running out of helium.
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