French astronomers have launched a campaign to fight light pollution.

Scientists at the world-renowned Pic du Midi observatory in the Pyrenees say light from surrounding cities is preventing them from getting a good look at the heavens.

Astronomer Thierry Roudier said: "It is important to preserve the sky for scientists and the public at large.

"When we observe the sky and the Milky Way, we have an idea of where we are in the cosmos.

"When we cannot see the sky then we are living in the dark and cannot see where man fits into the universe."

City officials in Toulouse have promised to dim their lights and switch to more energy-efficient bulbs.

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