Humans are searching for an alternative habitat and Mars is the most popular candidate in this regard.

A lot of space missions have been sent to the red planet in recent years in order to extract as much information as possible. In these circumstances, what if you get to know that NASA found signs of life on Mars, about 40 years ago, but they were destroyed. The 2 Viking robots that visited the planet in the later parts of the 1970s were the explorers as well as the destructors of this precious information.

The officials at NASA were delighted when the Viking twins, Viking 1 and Viking 2, landed on the Martian surface for the first time. It was expected that they will study the soil for traces of organic life and it will confirm the presence of carbon-based molecules on this planet. The Curiosity Rover of NASA has confirmed the presence of organic molecules on Mars earlier this year but none of the Vikings managed to extract any information about that. A recent study published in the Journal of Geophysical Research: Planets has the explanation about what went wrong there 40 years ago. According to researchers, carbon was there all along but the Viking spacecraft set it all on fire. Ames Research Center of NASA and the Atmosphere, Media, Spatial Observations Laboratory (LATMOS) joined forces to reveal all this and said,

“A total of four [soil] samples were analyzed, each multiple times, by rapidly heating the sample to one of four temperature steps.”

The authors of the study mentioned that the officials at NASA didn’t consider the soil composition of the Mars before heating the samples. There was a highly-flammable fuel in it which crushed the carbon contents into bits once the heating process was initiated. The samples of the Martian soil were heated to a maximum temperature of 500^o C in order to release any volatile organic molecules. The fact that the Vikings failed to get any carbon in the vapors came out as a surprise but it seems as if this recent study has solved this long-lasting mystery.

The roots of this research go back to 2008 when Perchlorate was found on the red planet. This salt was found by the Phoenix Rover near the North Pole of the Mars. At that time, scientists knew that this rare salt was used as a source of energy by the ancient microorganisms on Earth and they thought that it could have served the same purpose on Mars as well. However, the researchers of this study were interested in another property of this unusual salt. It is extremely flammable and is used to burn fireworks faster and make rocket fuel, these days. It provided an accurate explanation for the burning of carbon contents in the Martian samples.

The combustion of carbon with Perchlorate produces a molecule called Chlorobenzene which can stay in the soil for months. If this theory is to be believed, then there would have been traces of this chemical in the Viking’s oven. The data extracted from the Curiosity Rover showed that Chlorobenzene was present in the Martian soil in 2013. In order to strengthen their claims, the researchers of this study decided to go back to the Viking. They reexamined the original data sets again in their quest for Chlorobenzene and acknowledged that in the following words:

“We searched the Viking data for a possible reaction product between the salt and organics in the Viking oven.”

Their findings confirmed all the propositions about the presence of organic matter on Mars. The samples taken by the Viking 2 had trace amounts of Chlorobenzene in its oven. This meant that the probe had a good look at the organic compounds before setting them on fire. Despite all that, a lot of doubts are still revolving in the minds of the researchers. Melissa Guzman, a study author who is a Doctoral Student at the LATMOS research, mentioned that this latest finding cannot be regarded as a definitive proof of Martian organics because it is very much possible that the carbon compounds burned in the oven of the Viking might have come from the Earth. Contrary to that, some of the scientists have sealed the deal as they think that no further research is needed to confirm this fact.  Whether it is true or not, only time can tell.