Economist GMAT Reading Comprehension Challenge #16

Welcome to the 16th edition of the GMAT Reading Comprehension Challenge! If you’re just getting started with these articles go ahead and read the instructions on the GMAT reading comprehension challenge home page.

Article: New results suggest there is no methane on Mars

Link: https://www.economist.com/science-and-technology/2018/12/22/new-results-suggest-there-is-no-methane-on-mars

On earth…methane in its atmosphere.

• Most methane in earth’s atmosphere comes from living organisms.
• Presence of methane in Mars’s atmosphere could indicate presence of living organisms.
• Recent data shows no methane in Mars atmosphere, thus less likely that there are living organisms on Mars.

Previous observations…with spikes up to 7.0ppbn.

• Previous data from orbit, telescopes, and the Mars rover (Curiosity) indicated some Methane on Mars
• Data from Curiosity indicated that methane quantity increased and decreased with the seasons.

That cyclical pattern…under the planet’s surface.

• The methane ups and downs have intrigued researchers
• 2 possible sources of methane: carbon rich molecules from outer space space (meteors) or under the planet’s surface.

Methane from both sources will mix…lucky breaks do happen.

• Both sources would eventually mix in the atmosphere
• BUT, underground sources would be more concentrated near the ground and could be seasonal affected by geological, geochemical, or biological cycles.
• Biological cycles would indicate life on Mars.

Regardless of their source…this is bad news.

• Methane in Mars’s atmosphere would be expected to last for centuries
• The spectroscopic instrument called nomad was designed to detect this but found nothing
• Nomad was 20 times more sensitive than Curiosity,

The findings are still under review…taking accurate readings.

• The findings from Nomad are still under review
• At least some scientists not surprised as Curiosities readings were barely above control measurements.
• It is hypothesized that the methane that Curiosity detected was emitted by Curiosity itself but how is unknown.

The optimists will not be deflected…neither side is willing to give way.

• However, “optimists” point out that Nomad can only probe the upper part of the atmosphere and that a dust storm obstructed some of the data from being properly gathered.
• Still, Nomad shows that Mars methane is rare and confined to lower levels of the atmosphere.

Main Idea

New data indicates no methane in Mars’s upper atmosphere and casts doubt on whether Mars has any methane, a would be indicator of life on the planet.

Primary Purpose

To discuss the importance of a new finding.