Don't Dismiss Life on Mars Just Yet.

 

NASA's rover Curiosity was sent to Mars to explore Gale's crater, looking for the most part for the chemical markers that could indicate that in Mars' distant past, the Martian environment could have supported life.

Goldilock Zone Redefined

The Goldilocks Zone, according to the Wikipedia, is: 

• In astronomy and astrobiology, habitable zone (more accurately, circumstellar habitable zone ) is the scientific term for the region around a star within which it is theoretically possible for a planet with sufficient atmospheric pressure to maintain liquid water on its surface.

In the past this has been fairly easy to determine as, where ever the Earth was in reference to a yellow dwarf star, that was the habitual zone, and all other calculations could be made from this generality.  

Well Space.Com has an article that seems to throw a bit of a monkey wrench in to the mix.

In a recent article:

• Now scientists have redefined the boundaries of the habitable zone for alien planets, potentially kicking out some exoplanaets that were thought to fall within it, and maybe allowing a few that had been excluded to squeeze in.

What surprised me however was the redefined low end (how close a planet can be) for an Earth style system  was .99 AU.  Earth at 1 AU just barely makes the cut as a world almost too hot to maintain liquid water without it boiling away.  

Many astrobiologists are surprised at the closeness of Earth to the inside edge.  Plus with the new definition, many planets now fall into a to hot class not likely to harbor life.  

Read the Dvice article 

And a microbe shall lead them....

Past futurologist Timothy Leary is vindicated. As he predicted in 1977, genetic reproduction in a gravity free environment does indeed unlock or activate great swathes of the Terran genome, hitherto unexpressed.

At least that's what the results of a study recently released by the National Academy of Sciences suggest.

In "Space Flight alters Bacterial Gene Expression" the forty (yes 40) authors observed that:

"Salmonella bacteria grown aboard the Space Shuttle on its STS 115 mission showed changes in the expression of 160 genes, with the RNA-binding protein Hfq in command....Global microarray and proteomic analyses revealed that 167 transcripts and 73 proteins changed expression with the conserved RNA-binding protein Hfq identified as a likely global regulator involved in the response to this environment."

The researchers concluded that it was the absence of gravity that precipitated the novel gene expression.

Similarly in Exo-Psychology Leary wrote that "[t]he significance of extraterrestrial flight has not yet been fully understood. Just as land-dwelling organisms rapidly develop neural and physiological equipment for the new environment, this transition to zero-gravity and extraterrestrial radiation will trigger off genetic and neurological changes necessary to adapt to interstellar life.

But as microbiologist Elio notes in his Small Things Considered blog, zero gravity is likely but one of the environmental changes the E Coli aboard the Shuttle went through:

"Besides gravity, which is clearly the focus of this paper, they really should control for a less obvious but potentially much more important factor: radiation. Our atmosphere shields us from an enormous amount of the stuff. The bacterial cultures that flew got exposed to much higher levels of radiation than the cultures that stayed on the ground, so it's entirely possible that the increased virulence is due to a mutation and/or general stress on the DNA repair machinery.

Dove suspects that "the reason they didn't look at this is that it was much easier to do gene expression chip profiling, rather than doing whole-genome sequencing on both cultures."

In a related vein, the High Priest of Psychedelia described psychological/philosophical impacts of zero G on several veterans of the lunar expeditions, who experienced it for extended periods:

"The beginnings of exo-psychological adaptation can be noted in several lunar veterans who returned claiming cosmic insights (Mitchell), philo­sophic revelations (Schweickart), and rebirth symptoms (Aldrin). "

How, one wonders, has that held up for the new generation of International Space Stationeers? Ten years along, any neo-philosophers among them? What about their post- space station progeny?

(Image courtesy NASA and public domain)