APOD: Mars Methane Mystery Deepens (2019 Apr 22)

[APOD Robot]

Mars Methane Mystery Deepens

Explanation: The methane mystery on Mars just got stranger. New results from ESA and Roscosmos' ExoMars Trace Gas Orbiter, has unexpectedly not detected methane in the atmosphere of Mars. This result follows the 2013 detection of methane by NASA's Curiosity rover, a result seemingly confirmed by ESA's orbiting Mars Express the next day. The issue is so interesting because life is a major producer of methane on Earth, leading to intriguing speculation that some sort of life -- possibly microbial life -- is creating methane beneath the surface of Mars. Non-biological sources of methane are also possible. Pictured is a visualization of the first claimed methane plume over Mars as detected from Earth in 2003. The new non-detection of methane by the ExoMars Orbiter could mean that Mars has some unexpected way of destroying methane, or that only some parts of Mars release methane -- and possibly only at certain times. As the mystery has now deepened, humanity's scrutiny of our neighboring planet's atmosphere will deepen as well.

<< Previous APOD

This Day in APOD

Next APOD >>

[Ann]

I find the video confusing. Why is some of it in color and some of it in black and white?

Yes, I realize that the colorized part of the video doesn't represent real color, just a measure of methane concentration. But why the dichotomy of one colorized hemisphere of Mars and one black and white one? If Mars now lacks methane, wouldn't it have been better to produce two side-by-side colorized hemispheres of Mars, where one hemisphere was "all blue" and lacked the red signal of high methane concentration?

The detection of methane on Mars in 2013 sparked renewed hope that the methane was produced by Martian life forms and that Mars therefore harbours life. Now that the signal is lacking, isn't it time to ask harder questions? Is it possible for methane produced by biological life to turn on and off, if the life forms are still alive? Are there other explanations for the periodical existence of methane in the Martian atmosphere that are more likely?

Ann

[Iksarfighter]

Maybe we already contamined Mars with some Terra bacteries.

[JohnD]

Anne,
Presunably, the colour is where the data are?

I'd criticise the video for showing nothing about the geography under the colour contours. What structres are assocaiated with the methan plumes?

John

[Nitpicker]

I'd criticise the video for showing nothing about the geography under the colour contours. What structres are assocaiated with the methan plumes?

John

Here is another image originally published with the video:

Click to view full size image

[orin stepanek]

Maybe the Methane on Mars is seasonal???????????????

[smitty]

This APOD raises at least one request for clarification and a couple of questions: the text refers to an earth-based detection of methane on Mars in 2003, but the article to which this claim is linked is dated 2009 (please see https://svs.gsfc.nasa.gov/3574 ). Since earth-based detection of methane on Mars was claimed previously (regardless of whether it was in 2003 or 2009), have there been subsequent earth-based looks at this? If so, what have they found? And if not, why not?

[Chris Peterson]

I find the video confusing. Why is some of it in color and some of it in black and white?

None of it is in black and white. If that's what your monitor is showing, it needs to be calibrated or replaced.

Yes, I realize that the colorized part of the video doesn't represent real color, just a measure of methane concentration. But why the dichotomy of one colorized hemisphere of Mars and one black and white one? If Mars now lacks methane, wouldn't it have been better to produce two side-by-side colorized hemispheres of Mars, where one hemisphere was "all blue" and lacked the red signal of high methane concentration?

The visualization was made by using a photographic map of Mars, overlaying it with methane data where data are available, and then mapping it onto a sphere and animating the rotation. There are, of course, static maps of the same data. The intent here was to add the rotation.

[Chris Peterson]

Maybe the Methane on Mars is seasonal??????????????? :roll: :shock: :?

Every indication suggests that it is. The mystery is related to the problem that even within that understanding, the detection results are not consistent.

[BDanielMayfield]

My hunch is that sporadic methane on Mars is from a non biological source.

[Chris Peterson]

My hunch is that sporadic methane on Mars is from a non biological source.

Probably true. But still an intriguing mystery.

[Ann]

I find the video confusing. Why is some of it in color and some of it in black and white?

None of it is in black and white. If that's what your monitor is showing, it needs to be calibrated or replaced.

Yes, I realize that the colorized part of the video doesn't represent real color, just a measure of methane concentration. But why the dichotomy of one colorized hemisphere of Mars and one black and white one? If Mars now lacks methane, wouldn't it have been better to produce two side-by-side colorized hemispheres of Mars, where one hemisphere was "all blue" and lacked the red signal of high methane concentration?

The visualization was made by using a photographic map of Mars, overlaying it with methane data where data are available, and then mapping it onto a sphere and animating the rotation. There are, of course, static maps of the same data. The intent here was to add the rotation.

Right. I need to restate what I said. None of the video is in black and white, but the contrast between the wildly colored colorized part and the bland sort of natural color Mars is more than striking.

Do I take it that methane has only ever been detected in (or over) certain locations on Mars? So that the idea of colorizing the parts of Mars where methane has never been detected seems stupid?

And do I take it, too, that an updated version of today's video would not show any colorized parts at all, since no methane has been detected lately on Mars, or in the Martian atmosphere?

Ann

[neufer]

.
Maybe the Methane on Mars is seasonal???????????????

Every indication suggests that it is. The mystery is related to the problem that even within that understanding, the detection results are not consistent.

---

<<Astronomers saw some lighter or darker albedo features (for instance Syrtis Major) and believed that they were seeing oceans and continents. They also believed that Mars had a relatively substantial atmosphere. They knew that the rotation period of Mars (the length of its day) was almost the same as Earth's, and they knew that Mars' axial tilt was also almost the same as Earth's, which meant it had seasons in the astronomical and meteorological sense. They could also see Mars' polar ice caps shrinking and growing with these changing seasons. It was only when they interpreted changes in surface features as being due to the seasonal growth of plants that life was hypothesized by them.

During the [Mars] oppositions of 1892 and 1894, seasonal color changes were reported. The idea that Schiaparelli's canali were really irrigation canals made by intelligent beings was first hinted at, and then adopted as the only intelligible explanation, by American astronomer Percival Lowell and a few others. The visible seasonal melting of Mars polar icecaps fueled speculation that an advanced alien race indigenous to Mars built canals to transport the water to drier equatorial regions. Newspaper and magazine articles about Martian canals and "Martians" captured the public imagination. Lowell published his views in three books: Mars (1895), Mars and Its Canals (1906), and Mars As the Abode of Life (1908). He remained a strong proponent for the rest of his life of the idea that the canals were built for irrigation by an intelligent civilization, going much further than Schiaparelli, who for his part considered much of the detail on Lowell's drawings to be imaginary. Some observers drew maps in which dozens if not hundreds of canals were shown with an elaborate nomenclature for all of them. Some observers saw a phenomenon they called "gemination", or doubling – two parallel canals. The late 19th century was a time of construction of giant infrastructure projects of all kinds, and particularly canal building. For instance, the Suez Canal was completed in 1869, and the abortive French attempt to build the Panama Canal began in 1880. It is understandable that 19th century people who accepted the idea of a Mars inhabited by a civilization might interpret the canal features as giant engineering works.

[Chris Peterson]

Do I take it that methane has only ever been detected in (or over) certain locations on Mars? So that the idea of colorizing the parts of Mars where methane has never been detected seems stupid?

I don't think it's a question of where methane has been detected, but of where data exist. My interpretation would be that the uncolorized regions lack data, not that they show a zero methane level.

[TheZuke!]

Space faring cows briefly stopped on Mars back in 2013.

[BDanielMayfield]

My hunch is that sporadic methane on Mars is from a non biological source.

Probably true. But still an intriguing mystery.

It's nice when divergent thinkers are drawn toward the same thoughts.

Some salient info on possible non-biologic methane production, from wikipedia's Methane article:

The two main routes for geological methane generation are (i) organic (thermally generated, or thermogenic) and (ii) inorganic (abiotic)[28]. ... The more important source of methane at depth (crystalline bedrock) is abiotic. Abiotic means that the methane formation took place involving inorganic compounds, without biological activity, either through magmatic processes or via water-rock reactions that occur at low temperatures and pressures, like serpentinization.[29][30]

And from wiki's article on serpentinite:

Serpentinite is a rock composed of one or more serpentine group minerals, the name originating from the similarity of the texture of the rock to that of the skin of a snake.[1] Minerals in this group, which are rich in magnesium and water, light to dark green, greasy looking and slippery feeling, are formed by serpentinization, a hydration and metamorphic transformation of ultramafic rock from the Earth's mantle. The mineral alteration is particularly important at the sea floor at tectonic plate boundaries.[2]
...
Serpentinization is a geological low-temperature metamorphic process involving heat and water in which low-silica mafic and ultramafic rocks are oxidized (anaerobic oxidation of Fe2+ by the protons of water leading to the formation of H2) and hydrolyzed with water into serpentinite. Peridotite, including dunite, at and near the seafloor and in mountain belts is converted to serpentine, brucite, magnetite, and other minerals — some rare, such as awaruite (Ni3Fe), and even native iron. In the process large amounts of water are absorbed into the rock increasing the volume, reducing the density and destroying the structure.[3]

The density changes from 3.3 to 2.7 g/cm3 with a concurrent volume increase on the order of 30-40%. The reaction is highly exothermic and rock temperatures can be raised by about 260 °C (500 °F),[3] providing an energy source for formation of non-volcanic hydrothermal vents. The magnetite-forming chemical reactions produce hydrogen gas under anaerobic conditions prevailing deep in the mantle, far from the Earth's atmosphere. Carbonates and sulfates are subsequently reduced by hydrogen and form methane and hydrogen sulfide. The hydrogen, methane, and hydrogen sulfide provide energy sources for deep sea chemotroph microorganisms.[3]
...
Abiotic methane production on Mars by serpentinization

The presence of traces of methane in the atmosphere of Mars has been hypothesized to be a possible evidence for life on Mars if methane was produced by bacterial activity. Serpentinization has been proposed as an alternative non-biological source for the observed methane traces.[7][8]

[bystander]

ESA: First Results from the ExoMars Trace Gas Orbiter
ESA: Mars Express Matches Methane Spike Measured by Curiosity

[revloren]

Maybe the rovers ran over and killed the methane producing life on Mars?

[Boomer12k]

I am wondering if the recent DUST STORM messed with the current data...as it might dissipate the Methane...

:---[===] *

[smitty]

My earlier post here didn't generate a response, so I'm trying again (if at first you don't succeed, etc.). This APOD raises one request for clarification and a couple of questions: the text refers to an earth-based detection of methane on Mars in 2003, but the article to which this claim is linked is dated 2009 (please see https://svs.gsfc.nasa.gov/3574 ); which of these two dates is correct? And since earth-based detection of methane on Mars was claimed previously (regardless of whether it was in 2003 or 2009), have there been subsequent earth-based looks at this? If so, what have they found? And if not, why not? Thanks for any clarification on these points.