Other Life in the Universe?

If there is intelligent life elsewhere in the Universe, why haven’t they contacted us?

To understand our place in the Universe, consider the following.

The diameter of the Sun is over 100 times that of the Earth and the distance between them is 93 million miles. However, in relation to the rest of the Universe, the Sun is very small compared to some of the other stars, for example, VY Canis Majoris in the Milky Way galaxy! The diameter of that star is 3600 times that of the Sun.

There are thought to be over 200 billion (200 000 000 000) galaxies in the Universe, each with between 100 and 200 billion stars.

Each of these 20 to 40 000 billion, billion stars is surrounded by multiple planets which could potentially hold intelligent life and even civilizations, perhaps, for the sake of argument, 100’s of millions of them.

Assume 1 million of these civilizations can travel or send messages through outer space.

Assuming also that these space-exploring civilizations are evenly spread throughout a spherical Universe, how far apart are they?

The current estimate of the diameter of the observable Universe is 91 billion light years. Therefore, the volume of the Universe is approximately 500 000 billion cubic light years.

The average volume occupied by each space-exploring civilization would be approximately 500 million cubic light years. Consequently, the average distance between 2 neighbouring space-exploring civilizations would be approximately 8 million light years.

So, if our nearest space-exploring civilization wanted to contact us, on average it would take 8 million years to get here at the speed of light (186 000 miles/second)!