Some other tennis venues, such as those used for the Australian Open have sliding roofs - but that tournament is on hard courts, which react differently to a living surface like grass.

BBC: SPORT | Tennis | The Wimbledon roof debate

Both are trying to make a living on a planetary surface and both are trying to do this as efficiently as possible without wrecking their living conditions.

CNN: How the search for aliens can help sustain life on Earth

Some scientists still defend those results: the soil may have had microbes living on ice beneath the surface, they say.

NEWYORKER: The Martian Chroniclers

Yes, they are 16 to 24 year olds playing video games for a living, which is on the surface, a seemingly laid back profession.

FORBES: Yes, eSports Needs Sportsmanship Too

The ozone layer protects living things on the Earth's surface from the Sun's ultra-violet radiation.

BBC: Ill wind 'killed dinosaurs'

Coral reefs are home to 25 percent of the world's marine fish species, and cover 1 percent of the Earth's surface, making them the largest single living structure on Earth.

CNN: All About: Coral Reefs

But the increased ultra-violet (UV) solar radiation which the damaged ozone allows through to the surface of the earth is a threat to all living things.

BBC: By Environment Correspondent Alex Kirby

It will also examine the general chemistry of the sub-surface layers, to see if it is within the limits tolerable by living things on Earth.

ECONOMIST: Exploring Mars

This is the theory that life is not merely a surface scum which clings to the outside of planet Earth, but that living things, in the form of so-called extremophile bacteria which can tolerate infernal heat, penetrate several kilometres into the planet's interior.

ECONOMIST: Obituary

Residents living near a busy road which runs between the counties of Wiltshire and Gloucestershire have begun a campaign against surface noise.

BBC: A419 campaigners want 'noisy' road surface to be replaced