Europa Plus Water Does Not Equal Life
NASA gave one of its high-profile press releases this week to dazzle reporters: Europa, the icy moon of Jupiter, may have large lakes of liquid water under its icy shell, closer to the surface than the deep ocean long believed to exist miles down. The curious domes rising above the ice seem to indicate heating that suggests exchange of material from the core to the upper icy crust. Would the reporters resist the temptation to speculate about life?
Yes and No. Every source made the biological connection, some with reckless abandon, some with caution. PhysOrg blazed it in the headline, “Scientists find evidence for 'great lake' on Jupiter's moon Europa, potential new habitat for life.” The BBC News used life twice, telling readers that “Any liquid water could represent a potential habitat for life.” New Scientist was cautious, calling the possibility doubtful but not out of the question. Most restrained was Nola Taylor Redd at Live Science, who focused on the geology and merely ended with a quote from a planetary scientist who opined, “The material cycled into the ocean via these lakes may make Europa's ocean even more habitable than previously imagined. "The lakes may even be habitats themselves.” But NASA’s Astrobiology Magazine was ecstatic, using the L-word three times, claiming that the discovery is “bolstering arguments that Europa could support habitats for life.” The NASA press release itself mentioned life twice, biology once, and habitability twice.
As for liquid water, the elixir of life is turning up all over the place. Astrobiology Magazine claimed that even distant Pluto may have liquid water, along with Callisto, Ganymede (other moons of Jupiter), Enceladus, Titan (moons of Saturn), and Triton (the large moon of Neptune). Nola Taylor Redd, the author of this article, too, exercised similar restraint in this article about life. Although she stated that other liquid oceans in the outer planets extend the habitable zone, she said, "Such objects could contain not only liquid water but the necessary ingredients for life that Pluto probably lacks."
The next-generation Mars rover, the Mars Science Laboratory (MSL), nicknamed Curiosity, is set to launch November 25. True to form, reporters like Magee McKee at New Scientist tell readers that it is “ready to hunt for signs of life on Mars.” The JPL MSL Website states the mission objective: “The mission of Mars Science Laboratory, aka the Curiosity rover, is to search areas of Mars for past or present conditions favorable for life, and conditions capable of preserving a record of life.”
In another Astrobiology Magazine article, Keith Cooper won the prize for reckless use of the word life in a solar system article. Discussing the “methane habitable zone” that might make Titan a lively place [news flash: no life has been discovered on Titan], Cooper used the L-word 37 times. The secret to getting life from water is evolution: “We live on a planet where water is a liquid and we have adapted and evolved to work with that liquid,” an astrobiologist said in the article.
Three hypotheses can be constructed from the use of the word “life” by NASA and reporters: (1) Astrobiologists need to justify their existence; (2) Astrobiologists and reporters think the public is stupid; (3) It’s funding time again.
We are told that liquid water is a “potential habitat for life.” Louis Pasteur’s swan-necked flasks are even better habitats. Stocked with water and nutrients, they have been open to the air on a life-infested Earth for over a century, but remain sterile. Bottled water is a habitat for life, but if it were not clean, would you buy it?
By focusing on the potential for life on these distant, sterile worlds, scientists are distracting the public, like magicians stealing their wallets while they talk fast. The really interesting scientific question is how these worlds, all of them smaller than the Earth, could have any water after leaking heat for an alleged 4.5 billion years. Answer that, and quit the talk about life out there till you find some empirical evidence for it.