Manager David Holmes said the centre had decided to "brighten things up a bit" to contrast with the cold, grey winter outside.

As part of the theme, staff are running daily science shows about the human perception of colour.

The presentations, designed for primary school aged children, end with a big, bubbly science experiment, which draw a gasp or two from children and parents alike.

On Monday afternoon it was staff member James Pemberton's turn to play mad scientist and he turned a large test tube of blue water into a bright, bubbly purple colour.

Mr Pemberton explained the bright liquid was cabbage juice, mixed with water, with dry ice added to it to make a weak acid.

The acidity created a steaming, fizzling effect.

The liquid went from blue to purple and Mr Pemberton said it could even go pink with some added vinegar.

"People love the final experiment, which is colourful, bubbly and mad-scientist looking," manager David Holmes said.

Keen observers Abbie Grose, 7, and Jack Wells, 3, were particularly impressed by the experiment. 

Other colour-related amusements at the Discovery Centre include the planetarium show, "Jewels in the Sky", which explains to children why stars are different colours.

The science show runs seven days a week during the school holiday period, with two shows a day, at 12pm and 2pm.