Basic Information
Life On Mars has been an exciting topic of debate for several centuries now.
- The polar ice caps of Mars were first observed in the 17th Century.
- In the 1890s and 1900s, it was a popular belief that the Martian canals were signs of an advanced civilization on Mars.
- In 1965 the probe Mariner 4 took photos of the planet as it passed by, and discovered that conditions on the planet are not favorable for multi-cellular life as we know it.
- In 1975 the Viking program landed probes on Mars. The Viking Biological Experiments produced mixed results. One experiment, Gilbert Levin's Viking Labeled Release Experiment gave results that strongly indicated the presence of biological life on the planet.
- In 1996, NASA announced that the Allan Hills 84001 meteorite, which originated on Mars, held fossilized nanobacteria.
- Since then, analysis of the Nakhla Meteorite and the Shergotty meteorite suggests martian-originated biological signs as well.
- In 1998, the Mars Global Surveyor captured images of mysterious Dark Dune Spots on Mars. Proposed explanations range from Geysers to microbial life.
- In 2003, methane was detected in the thin atmosphere of Mars.
- In 2005, formaldehyde was detected. This and the methane suggest that either mars is very active geologically (which doesn't appear to be the case), or it has life on it.
- In 2008, the Phoenix (spacecraft) discovered water ice permafrost just beneath the surface of the planet, beneath a few milimeters of dirt.
The Ongoing Debate
Despite these notions and developments, scientists remain divided about life on Mars. The planet has a very weak magnetic field. As a result, it's atmosphere has been blasted off by billions of years of coronal mass ejections from the Sun. Such a thin atmosphere means next to no pressure, and liquid surface water. The planet is cold, and has no plate tectonics. None of these conditions favors the survival or evolution of life as we know it.
However, those objections and difficulties are far from being a nail in Mars' coffin. The Viking Labeled Release Experiment produced results consistent with microbial life in soil samples. Levin, the experiment's designer, maintains firm belief that there is life on Mars, and his experiment detected it. Of the 3 other test types that were conducted by the Viking probes, 1 tested positive for life, and the other 2 didn't. One of the two that didn't detect life (the GCMS experiment) also had a malfunction that kept it from registering soil samples were even gathered. Just sayin'. Scientific papers released in 2006 reveal that the GCMS experiment equipment was also significantly less sensitive than it was promoted to be at the time - even if it wasn't malfunctioning, it might have just been too insensitive to detect a small sample of life. Other scientific minds who've looked over Levin's viking data have found a cycle to the gas release in his results. This cycle is the same length as the Martian day, which is exactly what you'd expect if the chemical changes were being caused by photosensitive life making use of the sun's energy.
Add the recent subsurface water and atmospheric methane discoveries to Levin's test, and you may want to conclude that life definitively exists on Mars. However, the scientific consensus is that we just don't know. The mixed results of the Viking Biological Experiments could be explained by a large amount of Hydrogen Peroxide in the soil. This is the official NASA position today - that naturally-occurring hydrogen peroxide in the soil prevents any possible life on Mars, and was also responsible for the Viking test results. 30 years later, though, NASA still hasn't detected any actual hydrogen peroxide on the planet either.
Recent work by biologists suggests that life on Mars might use or produce Hydrogen Peroxide. In this way, both camps can be satisfied - life on Mars may have been detected by Levin, and at the same time Hydrogen Peroxide may be behind the test results. Peroxide may end working as a biological solvent, and may also be a byproduct of an alien form of photosynthesis. See Hydrogen Peroxide as Biological Solvent for more information.
Regions of Interest
Places on Mars that might harbor life:
- Planum Australe - the Geysers on Mars, Dark Dune Spots and "martian spiders" are interlinked features of the south polar region of mars that may be a form of geyser. Or, they may be colonies of martian algae, buried beneath ice. When the ice melts (as it periodically does) the water they live in evaporates, and the algae dries up and turns black. These "dark dune spots" appear in the springtime on Mars.
- Cydonia (region of Mars) - famous for the Face On Mars, Martian Pyramids, and several other very unusual geological features, that in numerous conspiracy theories are signs and remnants of an ancient extraterrestrial civilization that is being hidden by a government conspiracy. If your game has the little green men or alien grey style of martians, they'll probably be found in Cydonia.
- Underground - If the official NASA consensus (that hydrogen peroxide is produced spontaneously by ultraviolet light hitting the planet) is correct, then any life on the planet would have to be in the shade, under rocks, under ice, or otherwise sheltered from the UV light and the hydrogen peroxide. In such a scenario, the only life possible on the planet would probably be single-celled extremophiles.
Sources
Game and Story Use
- Very common in science fiction - especially early sci-fi - is the theme of martians invading Earth because their own planet is drying out and dying. See alien invasion and little green men for more ideas that would fit well in a pulp genre campaign.
- Nearly as popular is the notion that multicellular life lived there once, and died off. Ancient Ruins and maybe even a Von Neumann Probe await those brave enough to visit.
- NASA chose to disregard Levin's experiment, then proposed the surface has hydrogen peroxide that would kill all life there anyway. Likewise, NASA has taken great pains to discredit the Face on Mars and other Cydonia (region of mars) features, including allegedly doctoring photos. Bill Clinton announced that ALH 84001 contained fossilized microbes from Mars, and then within a year the Lewinsky scandal broke. There's plenty of fuel for any goverment conspiracy you want to decide is true in your campaign.
- See also Disclosure Project, which is tons of fuel for your fire.
- Scientifically speaking, the most likely life on Mars is probably carbon-based, single-celled, subterranean, and utilizes Hydrogen Peroxide as Biological Solvent. If that's too mundane for you, check out the alien biology page for more ideas.
- Life on Mars may strike back against astronauts. See Curse of Mars.