The Universe is quite big... According to space.com, it is at least 156 billion light years wide. Travelling at speed of light one would need 156 billion years to move accross it.

Given the number galaxies, stars and planets, it would be very unlikely that our planet is the only one where conditions allow for development of intelligent life...

However, the distance between them and us would probably make any "visit" impossible. This is assuming no faster than light travel is possible, according to our current knowledge of physics.

Not only the Universe is big, but it's also very old - approximately 13.7 billion years ! If you compare that to the estimated age of human race (160'000 years) , or to the time our civilisation spent looking in the skies (7'000 years including the ancient Egyptians), you soon realise that our "presence" was shorter than a sneeze at Universe scale.

Even if life developped anywhere near our planet, it's unlikely that this takes place during our short existence...

The only thing that could make an extraterrestrial encounter more likely would be a spectacular change in our knowledge of physics. What makes the encounter unlikely are two limitations:

• It is not possible to move faster than speed of light
• It is not possible to travel backwards in time

If any of these becomes possible, not only we could be visited by an extraterestrial form of life, but we could also start our own exploration of this big universe.

Until then, I don't think this will happend... I would have more chances to win the lottery jackpot.

Sorry for this, but keep dreaming ;-)