Other Life in the Universe?
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| Crab Nebula |
The idea that life is something that is unique to our planet has been perpetuated by various religions for a long time.
On the other hand, as our understandings of how things work has gradually increased, the number of people that believe that we are not alone increases exponentially. As the last two centuries have passed, science has helped us to grasp our place on this earth and shape our views of the universe and our place within it. Within the construct of our little blue planet, the framework where life can be found and is being found is continuing to expand.
Harsh environments which were once believed to be hostile to the advancement or continuance of life are now revealing to be thriving with life. Radiation, heat and extreme cold were thought to deter or eliminate life until recent discoveries. Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur.
As we know, what science once thought which were the necessities for life Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur the six essential elements has also been increasing. A recent discovery in a lake in California shows life can also survive with 5 of the basic ingredients of life and phosphorous being replaced by a toxic element “arsenic”.
In years prior cosmologists were only looking at planets which are known to be within what is called “the goldilocks zone”. These planets are not too hot, nor too cold and sit in an approximately same distance to their suns as earth does to ours. We now know that life can be found on the bottom of the ocean floor, without oxygenated water, extremely warm temperatures such as thermal vents with high pressure or within frozen lakes under glacial ice. Constant bombardment of radiation, or no light at all do not appear to stop life from surviving either.
Even if there is other life in the universe, is it intelligent? Is it possible that even if there is, can we make contact with them in some way?
Can life exist at the same time that human life on this planet is alive?
How long on other planets does life take to form?
Those are big questions that at this point no one can answer with absolute certainty.
According to Stephen Hawking and Carl Sagan, earth is in no way in a “unique” or “central” position in the universe. Based on the vast size and physical laws of the universe it would seem improbable for bacteria or some form of life not existing somewhere in the universe.
The odds are very high life exists somewhere outside of our solar system, but the chances seem low for contact at this time, especially with intelligent life based on the distances involved and the amount of time it takes for intelligent life to form.
In our one sample on earth, the first known fossils of life, are bacteria which are approximately 3.5 billion years old. If life has existed for that long, it was only since the 1970’s that we have started sending out radio signals and searching for signals from other intelligent life, it goes to show how small a window we have been looking and sending.
Imagine that life has existed previously somewhere in the universe or for a short amount of time only. Their planet could have been destroyed, their suns decayed, they could have annihilated each other in a nuclear war, or they could be in a solar system so far from us we will never reach them. The possibilities are mind blowing and yet so slim that we can interact with them.
Until we have a second sample of life or find ruins or evidence of other life, the countless theories are tantalizing but endless. With only one sample we can only make so many assumptions.
Even our assumptions through science have shown us that our range is much broader than once thought. With further research and advancements in technology we will make new discoveries that may help us to understand not only the cosmos, but on our own planet and surrounding planets which I believe will one day lead us to find a second sample of life.
As the saying goes “It would be a waste of space if we are the only life in this gigantic universe”. To the best of our knowledge the universe is expanding. At what point it will stop expanding, or starts to implode is difficult or perhaps impossible to calculate.
With projected proton decay we can theorize that eventually decay will destroy all stars or life. It's unlikely all life can survive forever. Eventually suns burn out, proton decay occurs and eliminates what was once in a specific solar system. Even if intelligent life did exist, there may be no proof of their existence remaining.
Is our earth on the fringe, and has other life has already existed in the past in other solar systems? Is there proof of it for us to ascertain? Even thinking about that is a huge concept. There are many questions we cannot answer and are unlikely to be able to answer. Until we are can explore our own small pocket of the universe before we can explore deeper areas of a gigantic place perhaps with no line of ending that we can ever cross.
Are we just the same beginnings of life which, left to repeat itself on certain planets set to certain conditions. It would be interesting if we find life which is similar or the same as ours. Based on recent discoveries there are planets which are very similar to earth is a number of aspects.
Is it possible they already contain life?
It's exciting to say the least. Can this question be answered within our lifetimes? Probably not.
Only continued endeavours will enable us to answer these questions and create new ones for future generations.
Our sample to this point has been so small. As I recently listened to a show with famous physicist Neil deGrasse Tyson in which he stated, “Our sample has been so small. Imagine taking looking into a cup of ocean water, you can’t state that there are are no whales in the Ocean based on that small sample”.
Panspermia theory states that life was brought to earth and other areas of the universe by asteroids, meteors and planetoids. Since we know that there is plenty of evidence of falling debris hitting earth and other planets, is it so hard to believe that if they contain or contained life, and that if the conditions are right life becomes active?
Seems highly plausible.
Evidence which may indicate life exists outside our earth. It is in no way conclusive.
-Martian meteorite ALH84001 has indications on the microscopic level of formations that appear to be have made by life. Has been debated to be real or possibly just appear to be made by microbes once on earth.
-Wow! Signal found by SETI in 1971. Since it has not been able to be duplicated, some people now believe it may have somehow been a reflection of a signal from earth or a naturally created phenomenon. Repeated attempts to listen to this area of the Universe have shown no more evidence.
-Nasa astrobiologists have found life at the bottom of a California lake which do not consist of the 6 basic ingredients thought to be required to make all life on earth. These 6 being carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus. In this case, arsenic which is considered toxic has replaced phosphorus.
One thing that we can all say regardless of religion or scientific beliefs is that the cosmos is an amazing place, which we have a lot more to learn about. Many unexplained phenomenon and theories cannot yet explain to us the astonishment one sees when looking at a distant star, the suns solar radiation eruption, the creation of a new Universe or the light up night sky.
In closing I can only say that theories help to give us possible explanations for why things exist and could be correct, but by no means conclusive until we have further evidence.
To think we are the only form of life is an archaic way of thinking as we used to believe the earth was flat, the dark was evil and the sun revolved around the earth. Science can help us explain our world in a way that is relevant across cultures and barriers.
We know for sure we are not the centre of the universe, and to think otherwise would be ethnocentric or (perhaps earthnocentric?), egotistical and erroneous. Perpetuating untruths is a sad aspect of humankind and hopefully as time goes by, more people will see that we no longer need to live in the dark, but can open our eyes and expand our horizons.
Biodiversity found here on earth is incredible, life in general is incredible and there is no definite answer to how it got here. The best theories supported by evidence are helping us to expand our knowledge and I hope one day we can answer the question is there other life within this vast and amazing universe we are just a small piece of.
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| The awe of the Universe is enough for me to contemplate our small place within it. |
Links you may find interesting
The ingredients required for Life
http://www.calacademy.org/exhibits/xtremelife/ingredients.php
Impossibly tight orbiting binary stars
http://www.latimes.com/news/science/sciencenow/la-sci-sn-binary-stars-20120706,0,6794019.story
Drilling on Mars for Ancient Life
http://zeenews.india.com/news/space/curiosity-rover-to-drill-into-mars-surface-to-find-proof-of-ancient-life_785955.html
Dust disk that appeared, suddenly disappears. Scientists baffled.
http://www.thestar.com/news/world/article/1221370--mysterious-dust-disk-in-space-suddenly-disappears-puzzling-scientists
Arsenic based life discovery in California Lake
http://io9.com/5704600/everything-you-need-to-know-about-nasas-new-life
