Strange Discovery on Titan Leads to Speculation of Alien Life
By Charles Q. Choi | Space.com
New findings have roused a great deal of hoopla over the possibility of life on Saturnís moon Titan, which some news reports have further hyped up as hints of extraterrestrials.
However, scientists also caution that aliens might have nothing to do with these findings.
All this excitement is rooted in analyses of chemical data returned by NASAís Cassini spacecraft. One study suggested that hydrogen was flowing down through Titanís atmosphere and disappearing at the surface. Astrobiologist Chris McKay at NASA Ames Research Center speculated this could be a tantalizing hint that hydrogen is getting consumed by life.
"Itís the obvious gas for life to consume on Titan, similar to the way we consume oxygen on Earth," McKay said.
Another study investigating hydrocarbons on Titanís surface found a lack of acetylene, a compound that could be consumed as food by life that relies on liquid methane instead of liquid water to live.
"If these signs do turn out to be a sign of life, it would be doubly exciting because it would represent a second form of life independent from water-based life on Earth," McKay said.
However, NASA scientists caution that aliens might not be involved at all.
"Scientific conservatism suggests that a biological explanation should be the last choice after all non-biological explanations are addressed," said Mark Allen, principal investigator with the NASA Astrobiology Institute Titan team. "We have a lot of work to do to rule out possible non-biological explanations. It is more likely that a chemical process, without biology, can explain these results."
"Both results are still preliminary," McKay told SPACE.com.
To date, methane-based life forms are only speculative, with McKay proposing a set of conditions necessary for these kinds of organisms on Titan in 2005. Scientists have not yet detected this form of life anywhere, although there are liquid-water-based microbes on Earth that thrive on methane or produce it as a waste product.
On Titan, where temperatures are around minus 290 degrees Fahrenheit (minus 179 degrees Celsius), any organisms would have to use a substance that is liquid as its medium for living processes. Water itself cannot do, because it is frozen solid on Titanís surface. The list of liquid candidates is very short -- liquid methane and related molecules such as ethane. Previous studies have found Titan to have lakes of liquid methane.
The dearth of hydrogen Cassini detected is consistent with conditions that could produce methane-based life, but do not conclusively prove its existence, cautioned researcher Darrell Strobel, a Cassini interdisciplinary scientist based at Johns Hopkins University in Baltimore, Md., who authored the paper on hydrogen appearing online in the journal Icarus.
Strobel looked at densities of hydrogen in different parts of the atmosphere and the surface. Previous models from scientists had predicted that hydrogen molecules, a byproduct of ultraviolet sunlight breaking apart acetylene and methane molecules in the upper atmosphere, should be distributed fairly evenly throughout the atmospheric layers.
Strobelís computer simulations suggest a hydrogen flow down to the surface at a rate of about 10,000 trillion trillion molecules per second.
"Itís as if you have a hose and youíre squirting hydrogen onto the ground, but itís disappearing," Strobel said. "I didnít expect this result, because molecular hydrogen is extremely chemically inert in the atmosphere, very light and buoyant. It should ífloatí to the top of the atmosphere and escape."
Strobel said it is not likely that hydrogen is being stored in a cave or underground space on Titan. An unknown mineral could be acting as a catalyst on Titanís surface to help convert hydrogen molecules and acetylene back to methane.
Although Allen commended Strobel, he noted "a more sophisticated model might be needed to look into what the flow of hydrogen is."
Scientists had expected the sunís interactions with chemicals in the atmosphere to produce acetylene that falls down to coat the Titan surface. But Cassini mapped hydrocarbons on Titanís surface, it detected no acetylene on the surface, findings appearing online in the Journal of Geophysical Research.
Instead of alien life on Titan, Allen said one possibility is that sunlight or cosmic rays are transforming the acetylene in icy aerosols in the atmosphere into more complex molecules that would fall to the ground with no acetylene signature.
In addition, Cassini detected an absence of water ice on the Titan surface, but loads of benzene and another as-yet-unidentified material, which appears to be an organic compound. The researchers that a film of organic compounds are covering the water ice that makes up Titanís bedrock. This layer of hydrocarbons is at least a few millimeters to centimeters thick, but possibly much deeper in some places.
"Titanís atmospheric chemistry is cranking out organic compounds that rain down on the surface so fast that even as streams of liquid methane and ethane at the surface wash the organics off, the ice gets quickly covered again," said Cassini team scientist Roger Clark based at the U.S. Geological Survey in Denver. "All that implies Titan is a dynamic place where organic chemistry is happening now."
Speculation íJumping the Guní
All this speculation "is jumping the gun, in my opinion," Allen said.
"Typically in the search for the existence of life, one looks for the presence of evidence -- say, the methane seen in the atmosphere of Mars, which canít be made by normal photochemical processes," Allen added. "Here weíre talking about absence of evidence rather than presence of evidence -- missing hydrogen and acetylene -- and often times there are many non-life processes that can explain why things are missing."
These findings are "still a long way from evidence of life," McKay said. "But it could be interesting."
Article from: Space.com
Video from: YouTube.com
Also tune into:
Richard C. Hoagland - Phobos an Ancient Alien Spaceship, Mars, NASA & Disclosure
Richard C. Hoagland - The Shemsu Hor (Sons of Horus), Ancient Cosmic War, Space Rituals & The Moon
Graham Hancock - Entangled, Supernatural, Shamanism & The Origins of Consciousness
Steven Greer - ET: Friend or Enemy? Disclosure & Free Energy
Joseph P Farrell - Cosmic War, Interplanetary Warfare & Mesopotamian Mythology
Walter Cruttenden - Lost Star of Myth and Time, Rise and Fall of Civilization and Consciousness
Wallace Thornhill - The Electric Universe
Seasons Discovered on Neptuneís Moon Triton
Moonís Water Comes in Three Flavors, Scientists Say
Google Liquid Galaxy Machine Sends Users on Immersive Tour of Earth, Moon, and Mars
Planet Triple Play: Saturn, Mars and Venus Appear Together
Can Planet X Nibiru Support Life? (Video)
Scientists discover Earth-like, water-rich planet: study
NASA: Evidence of life on Mars
Earth Microbes May Contaminate the Search for Life on Mars
Aliens íhijackí Nasaís Voyager 2 spacecraft, claims expert
Kuiper Belt Aliens and the 4th Reich - Stewart Swerdlow (Video)
Donít talk to aliens, warns Stephen Hawking
Microbes Could Travel from Venus to Earth
Mars rover finds signs of microbial life
The Hunt for Extraterrestrial Life Gets Weird
Latest News from our Front Page
Estonia must accept African & Middle Eastern immigrants says politician
Kalle Laanet, an Estonian politician, spoke at the International Migration Forum held in Tallinn. He told the audience that the question is not: Should Estonia take the African and the Middle Eastern immigrants (who illegally entered Southern Europe)? He said the question is: How will Estonia take the immigrants?
‚ÄúToday the issue is not whether Estonia should receive the refugees coming to ...
Rescuing Palmyra: History's lesson in how to save artefacts
With Islamic State militants now inside the historic town of Palmyra in Syria, the question, inevitably, is whether they will destroy the ancient ruins.
As IS continues to sweep through parts of Iraq and Syria, damage to centuries-old artefacts - because IS sees statues and shrines as idolatrous - is plentiful.
But history has shown that, when culturally important sites are under ...
Saudi Arabia Wants to Convert Sweden to Islam
Aje Carlbom is an Associate Professor of Social Anthropology, University of Malmö
Since the 1970s, Saudi Arabia has actively spread its interpretation of Islam, Wahhabism or Salafism, worldwide. It is the most literal version of Islam and affects many young Muslims, who regard society as a place to Islamize, writes social anthropologist Aje Carlbom.
Sweden's Foreign Minister Margot Wallstr√∂m was ...
Professor: If You Read To Your Kids, You're 'Unfairly Disadvantaging' Others
According to a professor at the University of Warwick in England, parents who read to their kids should be thinking about how they're "unfairly disadvantaging other people's children" by doing so.
In an interview with ABC Radio last week, philosopher and professor Adam Swift said that since "bedtime stories activities . . . do indeed foster and produce . . ...
If You Read About Conspiracies You're Just Like Osama Bin Laden Apparently
At its heart, the story of Osama bin Laden's time at his house in Abbottabad is surreal. The American image of bin Laden - leering at us from under his head wrap as he plots and schemes - is undermined by the mundane realities of his life. The guy was responsible for murdering thousands of Americans and orchestrating a global ...
|More News » |