G8_ Are We Alone?_grade level_03

Now consider how long it takes light just to reach our nearest neighboring star, Proxima Centauri. This journey, at the speed of light, would take almost four years to complete. Imagine you had an alien friend living on a space station in the Proxima Centauri system. If you sent them a text message, you would not get a response for eight years. It’s hard to imagine that it would take a little over four years for a signal to reach them. It would then take the same amount of time to send a return signal. It’s a good thing your friend lives relatively close.

Our galaxy, the Milky Way Galaxy, spans around 100,000 light years. The Andromeda Galaxy is the closest galaxy to our own Milky Way Galaxy. It is over 110,000 light years away. To send a message just across the Milky Way Galaxy and expect to receive a response, if there were intelligent life somewhere, you would need to wait 200,000 years to find out.

Using this method would be like throwing a ball over a high fence and waiting to see if anyone would throw the ball back. Instead of trying to actively communicate, a group of scientists are now merely listening to search for extraterrestrial life. If there is intelligent life out there and they had similar or even more advanced technology, they too might be releasing detectable signs of their existence into space. This is exactly why a group of scientists have set out to listen for those signals.