Space aliens DO exist – here's why
David Ramshaw, Border Astronomical Society
I would say there's definitely life elsewhere in the universe.
Technology is improving all the time. Every week they're finding stars that have planets around them that are the right size and distance from the star to have similar conditions to Earth. There must be life there.
They could house very basic life, like we started out with millions of years ago, or it could be much further on.
There's a lot more out there than just us. We're a small planet orbiting a small sun in the massive universe.
You just have to look at the photographs taken from the Cassini spacecraft from Saturn. You can see the Earth in the distance as a tiny little dot.
I would say we should search for intelligent life but it's impossible that we'll ever find it in a reasonable length of time.
The nearest planet with life could be thousands of light years away.
By the time they get a message from us and interpret it, it might take thousands of years.
In 1972 we sent out the Pioneer space probe which included a plaque with various symbols that indicated we are an intelligent life form.
Even now that's just moving beyond our solar system.
John Wickham, chairman of British UFO Research Association
There are millions of planets that contain the same things that are abundant on Earth.
So it's plausible that some form of life could exist elsewhere. It could be something like vegetation or bacteria.
We're an unbiased organisation. We can't treat reports as a believer or a non-believer. We just base our investigations on the available evidence.
Normally there's insufficient information. Sometimes you can identify it as an aeroplane that was flying there at that time, and it becomes an IFO - an identified flying object.
Ninety nine times out of 100 people say "Thank you, we just wanted to know what it was."
Sometimes they refuse to believe it and insist that it was extra-terrestrial.
It's not impossible for alien life to exist. There's a lot of anecdotal evidence, but no definitive proof.
We've been sending messages into space for years. It could take 100,000 years to get a reply.
Is it intelligent enough to reply? How would we decipher a reply? It's not going to be in English. If it's a radio message we might have missed it.
Stuart Atkinson, outreach worker and astronomer
I'm a firm believer in alien life. It would be a waste of space if it was just us.
I don't believe in UFOs that is a different thing.
Intelligent life is probably very, very rare, but life such as bacteria and fungus is more likely.
Cassini has found water on Saturn's moon Enceladus and where there is water there is usually life.
It is very promising. The chemicals are there, but they have to be in the right order. The building blocks are there.
Anything we find out now is promising, but it is small steps.
I have got some hope for Mars. It has water beneath its surface and there will micro-organisms there. In the Antarctic you find organisms in rocks that you crack open.
There is ice and permafrost on Mars, so there is a good chance there will be life, but we won't know until people go and explore.
Robots are good, but there is only so much that they can do. It takes people with intuition and an ability to spot something out of the ordinary.
In the Milky Way there are 400,000 million stars and for each one there is a galaxy, so it can't be just us.
Robin Leadbeater, internationally accredited astronomer, Wigton
The search for life is one of those key questions.
It is interesting to see that the conditions for life might exist independent of needing a lot of light from a star.
Normally, people talk of the 'Goldilocks' zone, where a planet is a certain distance from a star so it is not too hot or too cold and needing water to start life.
That limits the range of planets to us, Mars and Venus, but Cassini has discovered Saturn's moon Enceladus.
From a distance, it looks like a frozen snowball but they have found that there is liquid water underneath the ice and an ocean layer there which is created by thermal heat.
There is no evidence at all that there is any life anywhere else.
What we can say is that there are conditions for life to exist elsewhere in our solar system, but there is a big difference between having those conditions for life and life actually starting.