London - It is a question that has vexed mankind for centuries: Are we alone in the universe?
And according to a survey, it still tops the list of mysteries we are most desperate to see solved.
In second place was a curiosity for when a cure for cancer will be found, followed by whether it will ever be proven that God exists.
Further down the chart were more down-to-earth issues such as wanting to know if the fridge light really does go off when the door is closed.
Other top concerns in the poll of 2,000 people by TV channel Eden were the size of space and whether time travel will ever be possible.
Also featured was the classic conundrum of which came first, the chicken or the egg. - Daily Mail