The search for extraterrestrial life has been one of the longest enduring fascinations of the space age. While some would argue that Earth has already been visited by intelligences from elsewhere, astronomers searching for evidence that will satisfy the rigors of academia have probed distant galaxies using the enhanced optics afforded us today with modern telescopes, searching for clues about how life might come to exist elsewhere in the universe.
Though the search continues, in recent years there have been a number of instances where hopeful scientific minds have stumbled onto what may yet prove to be evidences of life in space. If not evidence of true “extraterrestrial” life, there are at least some odd circumstances that may have helped show us how and where alien life might be able to thrive along the way.
Just one year ago, Russian scientists made a bold–and unusual–claim about something they claimed to have discovered outside the International Space Station: evidence of sea plankton, along with other microbial agents. Almost immediately, the NASA officials expressed skepticism, and shortly afterward German scientists weighed in, as reported by Alejandro Rojas for the Huffington Post:
At an extravehicular activity Russian cosmonauts took samples from the outside of the Russian module. Those samples were then analyzed in a laboratory on Earth. Within this sample bacterial DNA was discovered.
However, the method by which the samples were analyzed in this case is disputed, as it cannot detect all kinds of bacteria and it also can not test whether the discovered bacteria are living and thriving or not.
Also the biomass that can be extracted from such samples is strongly limited so that at the moment no further tests could have been conducted on it. To do this, more samples would be needed.
The determination may indeed have been a false alarm, but it was far from being the first time that eyebrows had been raised regarding the possible discovery of biological life that might thrive in space. As far back as April, 1967, reports of a colony of streptococus mitis discovered within insulating foam in the cameras from Surveyor 3, used by Apollo astronauts on the moon, inspired curiosity about how bacterial life might withstand the harshness of space travel.
Then in 1992, an item retrieved from he Arkansas Democrat-Gazette detailed how a strange, bacteria-like substance had been discovered growing on the exterior of a bus-sized satellite called the Long Duration Exposure Facility, launched into orbit by NASA in 1984. In a small area on the exterior of the satellite roughly the size of a toothpick, a strange “growth” had been found near a darkened area of Teflon.
When observed under an electron scanning microscope, small stalagmite-esque protruberances were found, which were roughly one-tenth the width of the average human hair. It was determined at that time that the substance had not been fungal, nor did any evidence of mold present itself.
Within the framework of searching for extraterrestrial life, the question of whether life is truly as rare as it seems often appears, along with questions such as whether all “life” we might expect to find in the universe would necessarily possess traits we have come to expect from our observations of Earth biology. In 2003, Neil DeGrass Tyson wrote for Astrobiology on the scientific and cultural importance of the search for alien life, outlining the debate over whether life on Earth is even chemically of great significance:
Is life chemically special? The Copernican principle suggests that it probably isn’t. Aliens need not look like us to resemble us in more fundamental ways. Consider that the four most common elements in the universe are hydrogen, helium, carbon, and oxygen. Helium is inert. So the three most abundant, chemically active ingredients in the cosmos are also the top three ingredients in life on Earth. For this reason, you can bet that if life is found on another planet, it will be made of a similar mix of elements. Conversely, if life on Earth were composed primarily of, for example, molybdenum, bismuth, and plutonium, then we would have excellent reason to suspect that we were something special in the universe.
Given such reason outlined by Tyson, we find that within five years, NASA scientists were further reporting on the possible discovery of inorganic (i.e. non-carbon based) molecules which appeared to arrange themselves in structural forms that might bear “life-like” qualities:
[A]n international team has discovered that under the right conditions, particles of inorganic dust can become organised into helical structures. These structures can then interact with each other in ways that are usually associated with organic compounds and life itself.
This, while not truly “life” or anything extraterrestrial in itself, eludes to that ever-fascinating further possibility that we may one day encounter things not of this world, which rather than resembling life we would recognize, might better constitute life not as we know it.
In a universe that is already recognized as virtually infinite, an equally expansive host of opportunities must be recognized in our continued search for what strange mysteries, whether living, or merely life-like, may await.
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