The Existence Of Oxygen Doesn't Mean Life Exists On Other Planets

The journey to find out another life outside the Earth brings us to unknown places. In addition to the looking at the solar system’s moons, other planets around neighboring stars also spark our interest.

Water, as well as oxygen, are the predominant elements in our search. However, according to recent research, this goal is groundless.

The results from research conducted by the Department of Earth and Planetary Sciences of Johns Hopkins University lead to the need to have new criteria for the search. In particular, scientists simulated the air of extrasolar planets in a laboratory to see whether life could exist.

The first author of the study, Chao He, said that they conducted experiments to produce organic molecules and oxygen which are able to be the foundation of life in the laboratory. However, the results were not like what they expected. Life could not exist in this ‘fake’ atmospheres that scientists imitated. Therefore, oxygen and water are not the primary factors to guarantee the existence of life. Instead, scientists should consider carefully about the procedure to produce the molecules.

Back to billions of years ago, although there was no oxygen content like today, life still existed on Earth. This theory was based on the appearance of cyanobacteria in oceanic areas surrounding the geothermal vents.

It could be said that these were, on the Earth, the first living things to create oxygen through photosynthesis process at that time. Oxygen first appeared at the bottom of the ocean before reaching a large area of land. At last, bubbles rose to our atmosphere to make it full of oxygen.

This event is called the Great Oxidation, which was the factor for the existence of other living forms on Earth. That explained the reason why oxygen is a biomarker. The presence of oxygen indicates that life has already existed, proving this latest study wrong.

Head of the research, Chao He with his team conducted their experiments in a Planetary HAZE room (PHAZER) with unique design in a laboratory of Sarah Hörst co-author. They tested 9 different kinds of gas mixtures like ammonia, water, methane, and carbon dioxide by the heating method at temperatures ranging from 26-371 degrees Celsius.

The gas mixtures were similar to those at Earth-like exoplanets that have already been discovered. Also, the team exposed 9 mixtures to two energy types which are UV light and plasma. They are naturally occurring energy that mimics the process to activate chemical reaction to form life.

After 3 days running the room continuously, which is equivalent to the period of the exposure of gas to sources of energy in space, they made an analysis of collected data. Their finding is that both organic molecules and oxygen were created and could act as the life’s raw materials in various chambers.

The oxygen was produced without the need for organic molecules, as well as microbes. This proves that the journey to find out oxygen in other planets could offer human another shelter to live in someday. However, it does not indicate that we will discover any living forms there, not even microscopic.

Chao He said that it used to be suggested that organics and oxygen are main substances for life. However, he and his team could abiotically produce them in numerous simulations. This proves that although there are oxygen and organics, it is unlikely that the existence of life exists.