Scientists at a US science conference have said it is now time to actively try to contact intelligent life on other worlds and are debating just what the message from Earth should be.
The first problem i forsee is that aliens would not have evolved and developed the same technology as us on Earth. We know there is no life except us Earthlings in our Solar System and the nearest solar system is Alpha Centuri which is 4.367 light years away, or a tad over 20 trillion miles, while we recently discovered the light from an 11 billion year-old star so what if life formed on one of the planets revolving around that particular star which would be so far advanced of us that our attempts at contacting them would be the equivalent of us sending smoke signals to their email account.
In the opposite direction, we will not have the technology to catch communications sent by a civilisation many millenniums further down the communications evolutionary time line than us.
The chances of an alien civilisation having the equipment to not only catch our 'Hello Universe' message but to be able to decipher it and answer us in a way we would understand is less than negligible.
For all we know they may be sending us messages daily but we are not far enough advanced to know what they are and ignore them.
Secondly, do we really want to announce ourselves to a hugely advanced civilisation that would view us with as much disdain as we view an irritating insect or judge that we are a waste of good atmosphere and incinerate us on sight.
Thirdly, if science fiction films are anything to go by, the first thing the alien life form asks is to be taken to our leader and that needs sorting out if we are going to send out invites to them to come check us out because it would just be embarrassing in front of our intergalactic brothers and sisters if we just stand there scratching our heads while trying to work out exactly who the Earths leader is.