astrobiology (2)

Brine Europa...

Salt-laden water welling up from below gives Europa’s fissures and cracks their distinctive color.
Credit: NASA, JPL-Caltech and SETI Institute


Topics: Astrobiology, Exoplanets, Planetary Exploration, SETI

The sea sloshing beneath the icy surface of Jupiter’s moon Europa just might be the best incubator for extraterrestrial life in our solar system. And yet it is concealed by the moon’s frozen outer shell—presenting a challenge for astrobiologists who would love nothing more than to peer inside. Luckily they can catch a partial glimpse by analyzing the flavor of the surface. And the results are salty.

A new study published this week in Science Advances suggests that sodium chloride—the stuff of table salt—exists on Europa’s surface. Because the exterior is essentially formed from frozen seawater, the finding suggests that Europa’s hidden sea is drenched in table salt—a crucial fact for constraining the possibilities for life on the alien world.

Not that scientists have tasted a slice of the distant moon. To analyze Europa’s composition, astronomers study the light emanating from its surface, splitting it into a rainbow-like spectrum to search for any telltale absorption or emission lines that reveal the world’s chemistry. There is just one problem: Ordinary table salt is white and thus gives off a featureless spectrum. But harsh radiation—which exists at Europa’s surface in abundance—just might add a dash of color. That much was realized in 2015 when two NASA planetary scientists Kevin Hand and Robert Carlson published a study suggesting the yellowish-brown gunk on Europa might be table salt baked by radiation. To reach that conclusion, Hand and Carlson re-created the conditions on Europa within vacuum chambers—or as Hand calls them, “stainless steel shiny objects that are humming and whizzing.” Next, they placed table salt into those chambers, lowered the pressures and temperatures to simulate Europa’s surface, and blasted the samples with an electron gun to simulate the intense radiation.


Water on Europa—with a Pinch of Salt, Shannon Hall, Scientific American

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The Great Filter...

Image Source: Gizmodo and originally, Wait, But Why


Topics: Astrobiology, Carl Sagan, Climate Change, Drake Equation, Existentialism, Fermi Paradox, Nuclear Power

“The universe is a pretty big place. If it's just us, seems like an awful waste of space.” Carl Sagan

My First Contact scenario doesn't involve Vulcans, warp drive or impossible scenarios: it involves radio transmissions, as communication is a big part of the Drake Equation. Specifically audio, video and digital data (Internet?) of extraterrestrial origin as we would confirm before announcing to the world. Assuming the aliens developed their technology in an oxygen-nitrogen environment, the language we could hear might amount to a lot of "clicking" noises, that mathematicians - specifically specialists in cryptography, and linguists - would dive into deciphering. Eventually after coming up with a Rosetta Stone of syntax, we could translate what would amount to news, drama and sitcoms. Of specific interest might be their political climate and sectarian strife (if any). More particularly, did they successfully translate through their "Great Filter"...

...or, if they did not.


I'm a big fan of Jordon Peele's incarnation of The Twilight Zone, particularly the sixth episode: "Six Degrees of Freedom." It is unfortunate that popular show title describes our current political climate.

I won't give away the intriguing ending, but Peele has mastered the macabre plot twist of Rod Serling's writing style, and (my opinion) his surreal monologue delivery. It's streaming, so you may have to pay less than you would for a single movie ticket per month to view it. I've enjoyed it andother shows so far, and I get no monetary gain for the endorsement.

"The Great Filter, in the context of the Fermi paradox, is whatever prevents dead matter from undergoing abiogenesis, in time, to expanding lasting life as measured by the Kardashev scale.[1][2] The concept originates in Robin Hanson's argument that the failure to find any extraterrestrial civilizations in the observable universe implies the possibility something is wrong with one or more of the arguments from various scientific disciplines that the appearance of advanced intelligent life is probable; this observation is conceptualized in terms of a "Great Filter" which acts to reduce the great number of sites where intelligent life might arise to the tiny number of intelligent species with advanced civilizations actually observed (currently just one: human).[3] This probability threshold, which could lie behind us (in our past) or in front of us (in our future), might work as a barrier to the evolution of intelligent life, or as a high probability of self-destruction.[1][4] The main counter-intuitive conclusion of this observation is that the easier it was for life to evolve to our stage, the bleaker our future chances probably are.

The idea was first proposed in an online essay titled "The Great Filter - Are We Almost Past It?", written by economist Robin Hanson. The first version was written in August 1996 and the article was last updated on September 15, 1998. Since that time, Hanson's formulation has received recognition in several published sources discussing the Fermi paradox and its implications.

Using extinct civilizations such as Easter Island as models, a study conducted in 2018 posited that climate change induced by "energy intensive" civilizations may prevent sustainability within such civilizations, thus explaining the lack of evidence for intelligent extraterrestrial life.[5]" Source: Wikipedia/The Great Filter

The Great Filter is alluded to in science fiction with or without warp drive: Star Trek described global wars on Earth and the fictional Vulcan that involved their respective nuclear holocausts. For the Vulcans, recovery involved a relentless embrace of logic, or as I recall reading in a Trek novel, "reality-truth." For Earth, it essentially involved accepting help from the Vulcans after the human species was discovered warp capable through a singular genius with a funny name post self-induced Apocalypse, a Deus ex Machina plot device used since publicly performed Greek and Roman plays. We don't have warp drive, but we do have thermonuclear devices poised for Armageddon. We don't have Vulcans, but we once did have the Easter Islanders, just as once we had the Dodo.

I've often encapsulated The Great Filter in my own dictum: "intelligence is its own Entropy." I think when Carl Sagan was alive, the regressive forces we see now denying science, climate change; verifiable facts and reality were well engaged in his day of the original COSMOS. Slowly, shows like COSMOS lost their appeal to Game Shows cum Reality Shows, and as a country we reveled in our distractions, added as channels on cable and Internet multiplied like E. coli. and measles resurgence as well as our grasp of what is real and verifiable. In fact, we seek distractions in gadgets and online machinations in the constant need to fill "horror vacui."

In the east, nothing meant something, particularly in clarity of thought: Mu Shin No Shin - "the mind without mind" or more colloquially, "no mind." As translated from the martial battlefield to artists both martial and objective; and Zen philosophers, it offers a certain clarity that can be attained when not focused on minutiae detail, but accepted reality "as-is" after diligent practice. A practice like karate forms that takes years of repetition, dedication and study. That is the key to mastering anything, from martial arts to science to civics.

The stars are silent. Intelligence may be rare. Vulcans if existing may not be benevolent, and in the myopic attention span of the erect species of which I am member - "wise men"...fleeting in longevity.

We hope we're past The Great Filter. I'm not sure we are.


Related links:

The Great Filter Might Be What's Preventing Aliens from Reaching Us,
Joanie Faletto, Curiosity

The Reason We've Never Found Intelligent Life Might be Because We Are Already Going Extinct,
Climate change might be humanity’s "Great Filter." Karla Lant, Futurism

The Great Filter, a possible explanation for the Fermi Paradox – interview with Robin Hanson
Science, Technology, Future

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