LONDON: Red-faced astronomers have changed their minds about the colour of the universe. It is not a subtle cross between turquoise and aquamarine. It is vaguely beige. Or perhaps even mildly magnolia.

“I am embarrassed,” said Karl Glazebrook of Johns Hopkins University in Baltimore, Maryland. “I don’t like being wrong.” Dr Glazebrook and his colleague Ivan Baldry delighted the world in January when they combined the light from 200,000 galaxies within 2bn light years of Earth and calculated that the merged colour would be pale turquoise.

A rainbow is white sunlight split into separate colours by the prism of raindrops. By analysing the colours shining from different galaxies over the last 2bn years, collected by the Anglo-Australian Observatory in New South Wales, the two scientists were treating starlight as fossil information.

They combined the blue light from the young, hydrogen-burning stars with the russet tinge of the older “red giants” in the galaxies, and devised a computer programme that would convert the merged frequencies into the colour that a human eye might see. This proved unexpectedly to be a pale green. “It’s not my favourite colour,” Dr Glazebrook admitted at the time.

In fact, there had been a bug in the computer software. One starlight colour should have been interpreted as a kind of faded pink: the computer counted it as white.

“There was a huge green shift due to the erroneous white point,” the apologetic astronomer said. “It is our fault for not taking the colour science seriously enough.” —Dawn/The Guardian News Service.