
Take a look at this!! This is nicked from the bbc.co.uk website today and shows some real (exo)-planets orbiting a star only 25 light years away!! Now for those non-scientists out there, 25 light years is the distance light would travel in 25 years - light travels at 300 million metres per second, so it goes an awful long way in 25 years.....BUT, this distance is actually very short in astronomical terms. Many galaxies are about 100,000 light years across*, and there are millions of galaxies that fit into our Universe...... you get the picture. We're looking at real planets here that are still there - ie the light from many distant galaxies that we observe from Earth now, actually left those galaxies millions of light years ago and hence by now, they may have completely changed or even collided with neighbouring galaxies. In the case of these planets, the light left them 25 years ago in 1983!! Any intelligent (or it may be more accurate to say non-intelligent) lifeforms may just be watching the very early episodes of The Bill! It's unlikely there is life on these particular planets, however, but you never know! After all, they have found thriving bacteria populations at the centre of volcanoes on Earth and even in nuclear reactor vaults, so life can certainly exist in hostile environments.
*A colleague of mine, Susan C, has just told me that the distance from the Earth to the centre of our Galaxy is about 25,000 light years and we are only about half way in.
Have a great weekend!