The US rocket company says the customers have already paid for the flight planned for late 2018.
Environmental groups have launched a legal challenge to the government's rule change.
Huge numbers of draughty homes could stop it meeting emissions targets by 2050, a report says.
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Fuelling the jet engine in a supersonic car
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Apollo 1 fire has had a far-reaching legacy
Tesla chief determined to engage with Trump White House
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What do they do inside the House of Lords?