Related Experiment Video
Updated: Apr 19, 2026

05:00
Measuring Dissolved Methane in Aquatic Ecosystems Using An Optical Spectroscopy Gas Analyzer
Published on: July 26, 2024
1.2K
Mars atmosphere. Mars methane detection and variability at Gale crater.
Christopher R Webster1, Paul R Mahaffy2, Sushil K Atreya3
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. chris.r.webster@jpl.nasa.gov.
Summary
Mars has low background methane levels, but episodic high methane spikes suggest an unknown source. Curiosity
Area of Science:
- Planetary Science
- Astrobiology
- Atmospheric Chemistry
Background:
- Methane plumes on Mars have been observed but lack explanation.
- Previous models suggested methane from dust or meteorites, but these are insufficient.
- Understanding Martian methane is key to assessing potential habitability.
Purpose of the Study:
- To measure methane abundance in the Martian atmosphere using in situ data.
- To investigate the source of observed methane variations on Mars.
- To compare measurements with existing geochemical and atmospheric models.
Main Methods:
- Utilized the Tunable Laser Spectrometer (TLS) on the Sample Analysis at Mars (SAM) instrument suite.
- Conducted in situ measurements over a 20-month period at Gale Crater.
- Analyzed data for background methane levels and episodic high concentrations.
Main Results:
- Detected a mean background methane level of 0.69 ± 0.25 ppbv.
- Observed episodic methane spikes up to 7.2 ± 2.1 ppbv over 60 sols.
- Background levels are lower than predicted by ultraviolet degradation models.
Conclusions:
- Mars exhibits significantly lower background methane than previously modeled.
- Episodic methane releases indicate an active, unknown methane source on Mars.
- Further research is needed to identify the origin of this episodic methane.
Related Concept Videos
Microbes and Climate Change
73
Microorganisms are pivotal agents in Earth's biogeochemical cycles, significantly influencing climate dynamics through their metabolic activities. These microbes modulate the levels of key greenhouse gases by both contributing to and helping mitigate climate change.Microbial Contributions to Greenhouse Gas EmissionsRising global temperatures accelerate microbial metabolism, which, in turn, speeds up the decomposition of organic matter. This process releases carbon dioxide (CO₂) through...
73
Microbes and Methanogenesis
74
Methanogenesis is a critical microbial process in anaerobic ecosystems responsible for the biological production of methane, a potent greenhouse gas and valuable biofuel. This metabolic pathway is primarily facilitated by methanogenic archaea, which thrive in anoxic environments such as wetlands, sediments, and animal gastrointestinal tracts. The absence of oxygen in these habitats prevents aerobic respiration, thereby favoring alternative biochemical pathways for organic matter degradation.In...
74
Mass Spectrum
6.0K
A mass spectrum is the graphical representation of the relative abundance of the charged fragments in an analyte plotted against their mass-to-charge ratio (m/z). The plot's x-axis represents the ratio of the mass of the charged fragment to the number of charges it carries. The y axis of the plot represents the relative abundance of each charged species. The relative abundance is calculated from the signal intensity of each charged species recorded at the detector. The most intense signal (the...
6.0K
Volatilization
6.5K
Volatilization gravimetry is an analytical technique that measures the mass lost due to the volatilization of the substance. This technique is used to estimate the amount of volatile material in a sample. To perform this method, heat a known amount of the sample to a high temperature in a crucible or other suitable vessel. The volatile substance in the sample evaporates, and the vapor is completely expelled from the crucible either by heating the sample or bubbling a stream of inert gas through...
6.5K
IR Spectroscopy: Molecular Vibration Overview
6.7K
When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
6.7K
Global Climate Change
29.9K
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
29.9K

