What the heck is taking all of these aliens so darn long to contact us here on Earth? Why with all of the programs and technology have we not found them? Well the answer might just surprise you. With alien gift shops, stores and restaurants you would think we are ready for first contact but our wait may have just been extended.
Space.com states that the speed of light is 186,282 miles per second while traveling through the vacuum of space. So what we see in space is delayed by the distance and the time it took the light to travel to us. For an example the distance between Earth and our moon is 238,857 miles which means that every time we gaze up to the moon though our telescopes we are seeing the moon about 1.3 seconds in the moons past. This works well for objects that are considered closer but what about the far reaches of the universe? The measurement we use for those distant objects is light years. Light travels about 6 trillion miles in a light year. So again for another example, the closes galaxy to the Milky Way is Andromeda. Andromeda is about 2.52 Million light years away from Earth so light would take the same 2.52 million years to reach us. When we look at Andromeda we are looking at it 2.52 million years into its history or past. The vast distance it the reason for this phenomena.
So the speed of light which our eye needs to see is the one item causing us the largest grief. We continue to do two things, one look for intelligent life and two look for locations that we believe are inhabitable planets bases on its physical make up. First let’s look at the search for intelligent life.
The SETI (search for extraterrestrial intelligence) is a non-profit institute that conducts experiments in the search of intelligent life. SETI transmits signals and listens for signals from space. Again we run into the same issue, sending radio waves can only travel as fast as the speed of light. SETI became operational in 1985 so let’s assume that they started sending signals that very second in the search for life, we would currently be sending signals as far as 26 light years away. 26 light years isn’t even close to getting to our nearest neighbor Andromeda which again is 2.52 million light years away. This problem works in reverse for SETI also. They are also scanning for radio waves being sent from far way galaxies also so our reach is still quite limited. There are only two true hopes for SETI right now and that intelligent life has learned to travel to Earth and we pick up their signals as they pass into our 26 Light year threshold or that the advanced civilization from Andromeda is at least 2.52 million light years old and advanced enough to emit radio waves. Andromeda is estimated to be about 4.6 Billion years old so there is room for hope but the window looks much smaller than it ever has before. We would most certainly have to wait for them to visit us.
The second problem with that would be why would they come here? If they were from the edge of Andromeda looking in to earth it would be 2.52 million years ago. Most research states that humans have only been on this planet 2 million years. Homo erectus is estimated to have evolved 1.9 million years ago. If an intelligent species is on its way to Earth it is not for a visit with humans, it is most likely due to Earths vast resources which may not turn out so well for us.
I present you with the same issue as we look for inhabitable planets in distant space. NASA has the Kepler program which stated in 2009. This program helps scientists determine just how many Earthlike planets may exist in our galactic neighborhood. I know I have used some drastic examples of distance talking about the next closest galaxy but the next closest solar system is 10.6 light years away and Keplers closest Earth like planet is Gliese 581 c which is estimated to be 20.3 light years away. So if we had the ability to look closely at Gliese 581 c we would see it as if it was 20.3 years ago in its past and other life like planets will just be further than that away increasing the space between us and only making life that much harder to find. So as we search for life like planets the odds drop dramatically based on distance. The further we look out the further in history we see these planets and the same goes for those searching for us.
Satellites shorten the space between but not by much or even enough to really change the result. I leave you with this though, if we were traveling at light speed towards a planet like Gliese 581 c that was 100 light years away you would see the last 100 years of development of that planet in fast forward. Time for those on the plants would travel as normal but the traveler would see the last 100 years of growth in fast forward while they traveled. On arrival you would join their “now” but until you reached your destination the view would be amazing. Just imagine how much progress the human race has made in our last 100 years.