NASA’s Curiosity rover is the first to ever breathe the sweet Martian air.
At least, it’s the first to whiff the Red Planet atmosphere in millions and millions of years.
The automobile-sized rover’s analysis of the Martian air will be a huge help for scientists in discovering how and why Mars lost much of the planet’s original atmosphere.
Of course, Curiosity doesn’t actually breathe anything. It is a machine. But it utilizes a series of instruments to collect and analyze surrounding gases, including a mass spectrometer and a gas chromatograph. The atmosphere Curiosity recently sampled is from Gale Crater, near the “Rocknest” site where the rover is currently parked. The complicated group of tools is part of Curiosity’s Sample Analysis at Mars (SAM) instruments.
"With these first atmospheric measurements we already can see the power of having a complex chemical laboratory like SAM on the surface of Mars," said SAM Principal Investigator Paul Mahaffy, "Both atmospheric and solid sample analyses are crucial for understanding Mars' habitability."
SAM’s findings suggest that some of the planet’s original atmosphere has disappeared, and this affected the planet significantly. Scientists think this because heavier isotopes of certain elements were retained (isotopes are deviations of the same element with varying atomic weights). From this evidence, NASA scientists believe the top of the Martian atmosphere was lost to space, releasing the lighter isotopes into the Solar System.
SAM’s analysis reveals that there is 5% increase in the heavier carbon isotopes comprising the carbon dioxide in the current atmosphere than in the estimated original Martian air. There are also more of the heavy isotopes of Argon in the atmosphere now than in the theoretical past.
Astronomers believe the Martian atmosphere, climate and surface were very different. The planet may have enjoyed a denser atmosphere and even liquid water. Specifically, scientists are looking for evidence of methane gas. If it were present, it could be more evidence of ancient life on Mars. Unfortunately, Curiosity detected little to no methane.
"Methane is clearly not an abundant gas at the Gale Crater site, if it is there at all. At this point in the mission we're just excited to be searching for it," said SAM TLS leader Chris Webster, working at NASA's Jet Propulsion Laboratory in Pasadena, California, "While we determine upper limits on low values, atmospheric variability in the Martian atmosphere could yet hold surprises for us.”
However, methane is hard to detect from Earth, too.