Meanwhile, the search for methane is ongoing.
Two independent analyses were used to reach this conclusion, including computer simulations that assessed the probability of methane emissions from the Martian surface, and the identification of geological features within Gale Crater consistent with the associated methane spike. The probe has since found that the levels of the gas varies, rising and falling with Martian seasons.
Because methane gas dissipates relatively quickly - within around 12 years on Earth - and due to the difficulty of observing Mars' atmosphere, many scientists questioned previous studies that relied on a single data set.
On Earth, methanogenic microbes produce methane. Now the European Space Agency (ESA) has independently confirmed their findings, with methane eruption not only detected by Curiosity, but by the ESA's Mars Express orbiter as well. In the case of Mars, it's most likely that the methane is escaping from beneath the planet's surface.
Analysing the isotopic signature or atomic "strain" of carbon in the methane may help scientists determine whether or not the gas is sign of life.
It's difficulty to detect constantly suggests the methane is being released in intermittent spikes.
28 dead as rescuers struggle to reach storm-hit southern Nepal
Police official Sanu Ram Bhattarai said people were crushed by falling walls of their own homes and other debris. Further, the province government has urged the health institutions to provide free treatment to the injured.
Europe's Mars Express probe measured 15.5 parts per billion in the atmosphere above the Gale Crater on June 16, 2013.
Despite some speculation over methane on Mars, a group of scientists chose to conduct an independent investigation to see if the gas might exist on the Red Planet.
NASA's spacecraft have taken pictures of tens of thousands of those lakes out of orbit, and once rover Curiosity landed in 2012, it was sent back pictures of pebbles which were curved, campaigning for a quite long time in the bottom of a river.
Giuranna said, 'In general we did not detect any methane, aside from one definite detection of about 15 parts per billion by volume of methane in the atmosphere, which turned out to be a day after Curiosity reported a spike of about six parts per billion.
Curiosity's landing site in Gale Crater.
These riverbeds are a rich source of hints about the water flowing through them and the climate which generated it. "Let's just say it will make for an interesting discussion in the community as we seek to resolve the observations from existing and new measurements of methane on Mars". Meanwhile, geologists in the USA and Italy scrutinised the region around the crater for features that might release methane.
The ExoMars Trace Gas Orbiter, which is created to make a detailed inventory of the Martian atmosphere, was launched in 2016. Since permafrost is an excellent seal for methane, it is possible that the ice here could trap subsurface methane and release it episodically along the faults that break through this ice.