As most might know, the gas giants in our solar system all have a multitude of moons and natural satellites surrounding. Saturn has a whopping 62 moons, including the moon Enceladus, which has recently been found to have the possibility of harboring life.
If so, this could be one of the most important discoveries of humankind. Just what is special about Enceladus and what kind of life could it support?
I was, I remember, I still remember when the first time I pointed the telescope at the sky and I saw Saturn with the rings. It was a beautiful image. – Umberto Guidoni
Saturn’s Moon Enceladus
Enceladus is one of Saturn’s many moons and was discovered in 1789 by William Herschel while he was using his new higher-powered telescope for the first time. Enceladus was named after the giant named Enceladus in Greek mythology, who fought in the war between Giants and the Greek gods. Very little was actually known about Enceladus until the two Voyager spacecraft did a fly-by of Saturn and its moons in 1980. In 2005 the Cassini spacecraft entered Saturn’s orbit and was able to study Enceladus considerably more than what we have ever been able to do in the past.
Enceladus is Saturn’s sixth largest moon, coming in at a diameter of 310 miles wide. The entire planet is covered in thick ice that covers liquid water, just like what we have here on Earth. As far as “we” know every living thing requires water, but having water outside of Earth does not necessarily mean that there is life on that planet or moon. It’s one of those situations that life needs water, but the water itself does not necessarily mean life exists wherever it is. So, while the water on Enceladus does not automatically point to life, it is what is happening in that water that could lead us to a belief in life outside of Earth.
Life on Enceladus?
So just what makes scientists believe that Enceladus could harbor life? This is not an actual proven fact, of course, but there is an indication that Enceladus could house extraterrestrial life because of hydrothermal vents in Enceladus’ water. In the illustration above you can see along the bottom of the ocean that Enceladus has hydrothermal vents created by circulation along the crust, just like what we have here on Earth. When these vents erupt it sends jets of water through the ice, like a geyser. The reasoning for these vents is because of the existence of oceanic ridges along Enceladus.
On Earth, our ocean ridges typically aren’t habitable, but our hydrothermal vents are. Vents can house these underwater worms that can live in very inhospitable places that survive off the heat produced by the Earth as opposed to the sun. At one point the Cassini spacecraft flew through one of those plumes that erupted and we learned that the water is very similar to the ocean water we have here on Earth. The water also had the organic molecules including carbon dioxide and methane. That methane, researchers believe, could be the proof of life. It is very possible that microbes are living on hydrogen and are producing methane.
Researchers at the University of Vienna have done an experiment that mimicked the environment on Enceladus and found that the microbes can survive on the hydrogen produced from these hydrothermal vents and produce methane as a byproduct. To be perfectly clear, the methane produced is not necessarily created by microbes and could be just geological in nature, but there is a possibility that the methane is produced biologically. While this isn’t concrete proof of life, it is an incredible step towards our long search for life outside of Earth.
Could Life Outside of Earth Be Real?
Life, uh, finds a way – Dr. Ian Malcolm, Jurassic Park
When we think of aliens or extraterrestrials we think of those aliens from our nightmares who harvest humans for food. What we seldom think about is that life outside of Earth can constitute of a single microbe on another planet, or moon, than Earth. When you think about the possibility of life being that, then the idea of life outside of Earth isn’t so daunting. The search for life outside of our planet has gone on actively since the 20th century, but that question “are we alone” has been around since people began looking to the stars.
The universe itself is infinite, an idea that is extremely difficult to comprehend. With that idea in mind, it would be pretty darn near impossible for humans to be the only living creatures in an infinite universe.
When the Voyager spacecraft was launched in 1977 it had a very special payload, the Golden Record. Voyager’s mission was to do a fly-by of the gas giants and then continue on to interstellar space travel, meaning going beyond our solar system. With the idea of Voyager leaving our solar system, NASA and JPL took that opportunity and placed the Golden Record on the spacecraft. It contains greetings, songs, and pictures from Earth for any intelligent extraterrestrial life to discover. Aliens will be treated to Chuck Berry, coordinates of Earth, pictures of humans, and greetings from hundreds of different languages. Sure, this Golden Record is a record of human existence, but its primary function (and hope) is that it will be discovered by some sort of intelligent lifeform. The record is protected and will last for millions of years in space, just flying and doing its own thing. In fact, the Golden Record and Voyager spacecraft will outlive Earth.
In 2012 Voyager 1 left our solar system, making it the first ever human-made item to enter interstellar space. Maybe in 500,000 years from now, it will get into the hands of some intelligent aliens and humanity will be forever remembered, and recognized. Currently, Voyager 1 is about 11,000,000 miles away from Earth, and each day it goes further and further out into deep space. By 2030 Voyager will stop transmitting, so it will then become a vessel for the Golden Record, ensuring that humanity is never forgotten.