Objects resembling lichens and fungi

Lichens

Lichens are symbiotic organisms consisting of fungi combined with algae or cyanobacteria. There is close to 20 000 species of lichens in Earth. Lichens are extremophiles; they can live in very cold environments. The Lichen Buellia Frigida lives in rock surfaces in Antarctica. In images below are lichens resembling blue objects presented by Dr.Small.Opportunity Sol 2144, 2145, 2147 and Spirit Sol 327. In Curiosity Sol 1433 image there may be similar objects. Is the blue color caused by Blue Pigment, which would give cover in strong UV-light in Mars?

Opportunity Sol 2164

Opportunity Sol 2145

On Sol 1345 MAHLI images, Curiosity has driven over stones, which broke. Inside stones there is interesting patterns of white material. And on the non-broken part of stone there is lichens resembling brown object

In Curiosity Sol 890 images there is interesting structures on surface. Curiosity's laser has blown dust away from the surface of this structure. Usually the laser of Curiosity creates a hole to stone or sand. But in this case, has the material of this object expanded when heated? Martian lichens alive today? In Opportunity sol 3502 there is another lichens resembling structure

Lichens on Earth, Kirkkonummi, Finland.

See also very comprehensive article by Robert Walker, 2015: Places on Mars to Look for Microbes, Lichens, ... . Robert points out that for Earth microbes it has been previously thought that -20 degrees Celsius is the low limit life to survive. But recent studies show that bacterial activity inside glaciers survive -40 degrees Celsius. And there is even experiments with Colwellia psychrerythraea strain 34H to have activity at -196 degrees Celcius.

For the -20 degree Celsius limit for microbial life I have to point out one very simple and practical observation. I live in Finland where we have long cold winters. During the winter there can be several months long periods of -30..-20 degree Celsius temperatures. Both microbial life and macroscopic life have developed methods to easily survive these long cold periods. As example is image below from my backyard on winter (-30..-10 C) and on summer(+10..+30 C) and local wildlife surviving in these conditions.

Objects resembling fungi

Below left is Curiosity Sol 173 image, at site named John Klein. There is something white on the stone on the middle. On right is the same stone 13 mars days later, sol 186. The white material covers much larger area. In this place there are 4 of these white objects. One of them is in the low right corner under stone of this picture. And also look from middle of the picture to left to see one object in sideways. All of them are in shadow places, where the ultraviolet light of the Sun does not reach. Also they are under rock surfaces, which partly protect them from cosmic radiation. Could these shape changing white objects be related to white veins and nodules? From small images we can figure out that the object is there still 96 Sols later, Sol-269, when Curiosity came back again to investigate this area.

The temperature measurements of air by Curiosity indicated usually about +10..20 C on day and -80 C during the night. But twice, for some reason, the night temperature was only -5 C (Source: S.Djordjevic 2014: Simulating Martian conditions: Methanogen survivability during freeze-thaw cycles ). One of these cases is around Sol-190 where we now see growth in size of these white objects. The temperature of surface soil can reach +36 degrees Celsius for several hours during day at equator [63]. And salty Martian water is in liquid state in temperature range -70..+10 degrees Celsius [132,133].

For comparison to something similar on Earth: Below left and center: images of one species of fungi growing on a piece of wood on my own backyard during 15 days. In small image 28.3.2016 are the same fungi 5 months later after Finnish winter with snow and -20 degrees Celsius temperatures. Image on the right: Compare this fungus on the surface of a tree in Massachusetts, USA, to Sol 1103 object coming little further below. On Earth there are about 5 million species of fungi, and they have existed in Earth at least from Precambrian time 600 million years ago. The oldest fossil remains of Fungi on Earth are 2.4 billion years old, a discovery by Geologist Birger Rasmussen from Curtin University in Australia: Peter Dockrill April 2017, The World's Oldest Fungus Might Have Just Been Found Buried Under South Africa