Are MER photographs showing extant Martian organisms?

27 April 2004: This was published in Marsbugs, in two parts: the first came out on the 20th of April (Vol. 11, issue 17); the second in issue 18, on the 27th. In between, I received some interesting feedback that prompted me to expand the Discussion section. (Thank you Editor, Dr. Thomas!)

2 May 2004: Hay versión en castellano. The Spanish version is more a retelling than a translation, and prompted minor improvements and corrections to this here English version. A striking example of a marine living organism whose shape can be imitated by a freshwater calcium deposit can be found here. The document you are viewing is formatted according to w3.org specifications [6].

DO MER PHOTOS SHOW EXTANT MARTIAN ORGANISMS?
By Francisco J Oyarzun (francisco-o@earthink.net)

Introduction

The Mars Global Surveyor satellite has found intricately-branched formations of approximately radial symmetry (popularly known as "Clarke Trees" [1], "Fractal Forests" or "Martian Spiders" [2]) at latitudes between about 60 and 82 degrees south, whose photographs have been posted on the Malin Space Science Systems' website since October 2000. In the scientific literature, few are the authors (notably Ness and Orme [2]) who have dared to suggest that these might actually be gigantic living organisms, sprawling hundreds of meters in every direction. In the case of the annually recurring "Dark Dune Spots," also photographed from Mars orbit at similar latitudes, also suspected by some to represent (colonies of) living organisms, the Hungarian team of Horváth et al [3] have proposed a very plausible mechanism for habitability, namely: that Autumn and Winter (in South Polar regions) deposit a thick layer of water ice, followed by CO₂-ice, which in Spring evaporate (in last-in-first-out sequence) leaving, for several months each year, a layer of liquid water under the water-ice and over the dark spots, warmed by 24-hour sunshine. Yet, despite their observations and explanation, in numerous papers and conference presentations, the whole topic of extant life on Mars is still being treated as "taboo" by most planetary scientists.

I hereby make a plea for ending said taboo, based on recent photographs taken by the MER rovers "Spirit" (in Gusev crater) and "Opportunity" (on Meridiani Planum), photographs available on NASA's "raw image" galleries [4]. I present my case, as of mid-April, 2004.

Materials and Methods

The photographs I show here are all clippings from NASA's gallery of raw images at their Mars rovers website [4], particularly from the Microscopic Imager. These are offered to the public in jpg format, 32-bit grayscale, 72 dots per inch, and various degrees of compression (some with quite noticeable compression artifacts). For viewing originals online, I recommend setting the screen resolution to 72 dpi, which probably gives the best viewing experience. Unfortunately, the cameras were not equipped with autofocus zoom, so most of the originals are badly out of focus; the rover teams have attempted to compensate for this by photographing each scene several times, with different focal settings at each take, and much of the viewer's search time can be devoted to selecting the take that is least blurred. Even with the best focus, however, many of the details I wish to highlight here are small (in number of pixels) and/or have poor contrast. For this reason, I have in many cases taken the liberty of including, alongside the unretouched clipping, a 15% normal edge sharpening (in the parlance of GraphicConverter, which has been my sole image editing tool [5]): wherever a clipping appears twice, the reader may assume that the rightmost instance has been enhanced in this manner.

Results

The NASA-posted rover images (over 25 thousand as of April 20th) contain a number of striking, though so far sporadic, instances of organic (even bizarre [7]) shapes which I am not including here; in this report I wish to emphasize that there are motifs that not only look organic, but recur, with variations, across many images, and usually from both rover sites. To wit:

Arced filaments in radial pattern, detached from substrate. Figure 1 shows a detail from 3 images delivered by Spirit on Sol 66 (March 11th) at the rim of Bonneville (a 200m crater within the larger Gusev). Hopefully, the reader can see (bottom left) arced filaments in a radial pattern, at least two of which cross a shadow, indicating that the arcs clear the stone from which they seem to emanate.

Such fragile structures could not possibly have survived ejection when Bonneville was formed, so they must have formed in situ. Moreover, they look so fragile that they can hardly be "ancient" in any geological sense. They must therefore have grown there, recently.

I have yet to find (April 14th) another example of such filaments in Gusev panoramas, but Figure 2, from Opportunity's Microscopic Imager (Sol 73 = April 8th) shows several instances of neighboring pebbles connected to each other by wispy bridges, and, in several instances, a tenuous radial pattern over a pebble can be discerned.

Silky filaments resembling cobwebs. There exist "flowing" and even "lacy" patterns in some rocks, on Earth as well as Mars. Figure 3, however, shows a cobweb-like structure, in profile (lower right), that wraps around features of the underlying rock, and is therefore more recent than the rock that it covers. Strands of this webbing ("silk") are too fine to be seen individually, even at the magnification of the microscopic imager, but their presence can be inferred by the fact that they trap particles that can be seen suspended over cavities, in mid-air, sometimes forming "dotted lines." Strands so thin are of necessity very fragile; considering that Mars has two windy seasons every year, one has to infer that some process renews these strands, year in, year out. The dearth of oxygen in the Martian atmosphere (0.13%) makes it hard to believe that there could be animals moving about. And yet, if one posited that the filaments grow on their own (like hyphae, or by some peculiar geological process), one would have to explain how they manage to bridge a gap, in different orientations, with enough tension and adhesiveness to make those dotted lines.

In Figure 4, we see two instances of a cocoon-shape, much larger than the particles of Figure 3, suspended by invisible "silk" inside a rock cavity. We also see "squiggles" projecting from the cavity wall.

Figure 5 shows more suspended (sequestered?) and apparently silk-wrapped miscellanea, from the same "sweet spot" on Meridiani Planum (Opportunity, Sol 65).

Heads at the end of thin stalks ("sporophytes"). In some cases, the "miscellanea" that project from cavity walls take on the appearance of moss sporophytes (seta + sporangium): Figure 6 shows thin semirigid stalks capped by ovoid heads, but two of the heads are constricted in the middle. Sometimes such structures fan out in tight bunches (top right, and inset).

Figure 7 shows an exceptionally large head, dangling from a (relatively) white thread. I challenge the reader to show an example of a mineral growing that way without biological assistance, although biogenic cave deposits do come to mind.

Curls. A larger squiggle than the ones surrounding the "cocoon" of Figure 4, can be seen in Figure 8, photographed at Gusev, in sun and in shade, two-and-a-half hours apart. It appears crescent-shaped in both cases, except the crescent's opening is in opposite directions. I surmise that the shape is helicoidal, slightly more than a full turn, with one (lower) end attached to the rock, and that the apparent movement is an illusion caused by the differing illumination.

Extrusions and "star mouths." Even before Spirit left its landing pad, rover team members were struck by the unexpected degree of cohesiveness or "muddiness" of the Gusev regolith. But it takes more than cohesiveness to explain the extruded appearance, with obvious directionality, of the silt(?) in Figure 10A, also from Gusev. Now that we have seen filaments, is it not reasonable to suspect that these "worm droppings" are being held together by some kind of hyphae or tissue that had some reason to orient themselves in a preferred direction?

Actually, there is more to these extrusions(?) than directionality. Figure 10B is from the exact same take as 10A, and shows similar textures, in the shape of mouths, with cross- or star-shaped operculi. Are we looking at organisms, that start out as "mouths" and end up as silt-covered squiggles?

Monolayer of pebbles over sand. Speaking of cohesiveness, is it not remarkable that, when Spirit dug into the sand bank named "Serpent" on Sol 73, it would find that the sand bank was capped by a monolayer of round pebbles(?), of almost uniform size, but that there were none such in the sand below? Could such "pebbles" have grown in situ, in a light-dependent process? Figure 11 shows that most of these are far from simple!

Additionally, there are naked (and shiny) near-spherical pebbles, in a narrow range of sizes (dubbed "blueberries" by the Opportunity team), abundantly at both sites. They seem oddly incongruous amid the shards, pyramids, and jaggies of Gusev: see, for example, the splendid color photographs at keithlaney.com. Could it be that those are but the naked remnants of the filigreed "pebbles" of Figure 11?

Strings of what? From a distance, sand banks take on the color of the pervasive brick-colored dust, whereas the sand under the monolayer of "pebbles" is dark, as could be seen after the rover caused a little avalanche. Figure 12, from the same sand bank named "Serpent," shows a long vertical filament studded with bumps, that survived the avalanche, along with other similar filaments in the dark sand. Are these some kind of root, or are they organisms in their own right? (Thermodynamically, at least, a non-photosynthetic organism buried in sand could in principle make a living off the simultaneous presence of oxygen and carbon monoxide, continually replenished by the solar wind's interaction with the Martian ionosphere.)

"Belly-up pillbugs." On Sol 60, Spirit abraded a rock named "Humphrey" and, in so doing, uncovered the fossil-like patterns I show in Figure 13. These are bilaterally symmetric, with a segmented(?) line or cord in the plane of symmetry, from whence markings like ribs (veins? legs?) project.

Compare that with the much larger, dust-covered object in Figure 14 (Spirit, Sol 50). Do those all belong in the same phylum?

Do we have a jumble of such in Figure 15? If so, then here's a conundrum: the "belly-up pillbugs" of Figures 14 and 15 are bilaterally symmetric, yet the "jumble" (Fig. 15) comes from the same monolayer of "pebbles" as shown in the clippings of Fig. 11 A and B, where we saw a number of apparently similar features that are radially symmetric. The question is: are the "mouths" of Figure 11 a form intermediate between radially and bilaterally symmetric?

On Earth, the usual state of affairs is that a macroscopic organism does not, during the course of its macroscopic size, undergo a change of symmetry. Then again, consider the round seed (radially symmetric, at the resolution of these photographs) of a barrel cactus: it germinates to unfold a pair of cotyledons (bilateral symmetry), and subsequently grows into a radially symmetrical barrel.

Discussion

April 26: In the days since publication of Part 1, I have received feedback from paleontologists and others, to the effect that (a) the shapes shown here do not correspond with any known fossils from Earth; (b) biogenicity of these shapes is far from proven. I'll take (a) at face value, and agree, of course, with (b): in fact, I have posted, here, a striking example of calcium carbonate, on our planet, imitating a colony of tunicates.

What we do have right now, with respect to Mars, is a falsifiable hypothesis that claims that at least some of the shapes in figures 1 through 15 are biogenic ("hypothesis A"). To counter that, a different explanation ("hypothesis B") has to be offered that is at least as precise: "it could be anything" is not sufficient. For example (see figures 6 and 7): suggest a natural, nonbiological mechanism that produces a bunch of free-standing heads at the end of thin stalks anchored in rock (or, produces a head dangling from a filament), or, at the very least, show a specimen of such structures, known by scrutiny to be non-biogenic; then we'll have a valid counter to hypothesis A.

It used to be that hypothesis A could be ruled out a priori, on the grounds that

1. The planet is too cold, too dry, and the atmosphere too thin, for liquid water to exist at the surface, and therefore too dessicating for any life form that we know of.
Status: Said physics is true of pure water, but not necessarily of brines. A team of scientists (including Nathalie Cabrol, the original proponent of Gusev as a landing site, and currently part of the Spirit team [8]) found natural brine pools in Antarctica that stay liquid down to minus 50ºC —and, they do harbor life. Price and others [9] have confirmed metabolism down to at least minus 20ºC.

2. (Hitchcock and Lovelock's objection, 1967 [10]): the composition of the atmosphere does not reflect any photosynthetic activity.
Status: in a paper currently under review, I examine the ratio of two gases that had not been detected in 1967, namely, carbon monoxide and oxygen, reportedly generated in a 2:1 ratio in Mars' ionosphere, but present in the atmosphere at 800 and 1300ppm respectively. I conclude that the measured atmospheric ratio thereof is consistent with a low level of photosynthesis, especially one that fixes CO and releases CO₂.

3. Viking's labeled release experiments came out negative.
Status: Since 1997, over a dozen peer-reviewed papers have come out to dispute that claim [11].

So the least we have, right now, is a loss of certainty that Mars is either dead, or at best harbors subterranean microbes. Perhaps 2004 will be remembered as a turning point. On January 1st, the mission planners had been so certain that they could not possibly find evidence for extant life on the surface of Mars, that there was not even a spectrometer on board capable of detecting organic pigments. Suddenly, images come back that challenge that assumption. We go from there's no way (there can be macroscopic organisms alive today on Gusev, or on Meridiani) to: "prove it!".

MER images have been coming in, almost daily since January, and are now expected to continue at least until September. I entreat anyone with a serious interest in actual organisms (Mars bugs!) to examine the originals with a collector's eye: even in the clippings I've shown here, there are organic shapes other than the ones I've pointed out (example: "tiny mouths," individually and packed). The amount of data coming in from the ground every week now, is more than all the ground-based data in existence on New Year's Day, 2004. But to maximize the return, we need to see more closeups of stones with holes in them, particularly from Gusev: stones like the ones I show in Figure 16, for example. If you, dear reader, think you can convince the Spirit team to do that, please do try!

Acknowledgements

I thank and congratulate all the scientists, engineers, and support personnel that have designed, built and monitored the MER rovers; the US Congress and taxpayers for footing the bill; my family for their tolerance of this obsession; and Dr. David J Thomas for publishing this paper in record time!

References and Endnotes

The document you are reading is at
http://homepage.mac.com/ttelos/BioMars/OrganisMER/orgA.html
The author would like to be contacted at francisco-o@earthlink.net

[2] Martian "spiders." Ness, P.K. and G.M. Orme:
Spider-Ravine Models and Plant-Like Features on Mars: Possible Geophysical and Biogeophysical Modes of Origin
Journal of the British Interplanetary Society, Vol 55 No 3/4, Pp 85-108 (March/April 2002).
That paper, its followups (including one in Marsbugs, 9 June 2003), related reports by other authors, and many remarkable images, can all be accessed from
http://www.martianspiders.com/

[3] Hungarian team. A. Horváth, T. Gánti, A. Gesztesi, Sz. Bérczi, E. Szathmáry, and recently T. Pócs, have been writing about seasonal "Dark Dune Spots" as possible biomarkers since 2001. A compilation of their analyses and observations over nearly two Martian years is in
Origins of Life and Evolution of the Biosphere 33, 515-577.
They presented three papers to the Lunar and Planetary Science Conference XXXV (March 15-19, 2004):
http://www.lpi.usra.edu/meetings/lpsc2004/home.html

[6] html et al.:

formatting commands for this document are in html 4.01 transitional, charset=utf-8, with css level 2, according to standards set forth by the World Wide Web Consortium:
http://www.w3.org/
Browsers that implement those standards can be downloaded for free, for various platforms; for example, at mozilla.org

[8] Subzero liquid. Antarctic hypersaline ponds, liquid to -50ºC; interstitial unfrozen water, down to -80ºC:
Wynn-Williams, D.D., N.A. Cabrol, E.A. Grin, R.M. Haberle, C.R. Stoker
Seepage Channels as Eluants for Subsurface Relict Biomolecules on Mars?
Astrobiology Vol 1, No. 2, pp 165-184 (2001).

[9] Subzero metabolism. For a recent review, see Price, B.F. and T. Sowers:
Temperature dependence of metabolic rates for microbial growth, maintenance, and survival
Proc. Nat. Acad. Sci. Vol. 101 No. 13, pp 4631-4636 (March 30, 2004).

[10] Dead atmosphere. Hitchcock, D. R., and J. E. Lovelock:
Life Detection by Atmospheric Analysis,
Icarus Vol. 7 pp 149-59 (1967).