If you live in East London, there's a probability of just under 50 percent that you believe there is life on other planets.

But if you live on Gauteng's West Rand you're almost certain to be sceptical.

These are some of the findings of a poll released by TNS Research Surveys on Wednesday, only days after NASA launched a probe to seek out potentially life-bearing planets around other stars.

The survey was conducted among 2000 adults in metropolitan areas, one in three of whom said they believed there was life out there.

A quarter of them gave a "don't know" response, while 43 percent said they did not believe, according to TNS spokesperson Neil Higgs.

Black and whites were more likely to believe than were coloureds and people of Asian origin.

East London had the highest percentage of believers — 47 percent — and the West Rand the lowest — a mere five percent.

Higgs said TNS had found that people with the least education were the most likely to say "don't know" and the least likely to believe.

The survey did not ask people what form they thought the life would take.

Higgs, himself an amateur astronomer, said he was "absolutely" convinced that there was life on other planets.

"I don't think there is a shadow of a question of doubt," he said.

"I'm very aware of the awesomeness of the universe, and its incredible size. There has to be something out there."

Scientists have already detected more than 340 planets circling stars beyond our solar system.

Sapa