The Rugby Football Union's head groundsman has lifted the lid on why the sky turned orange earlier this week.

Residents across Richmond borough were all wondering the same thing when the night's sky became a luminous orange on Thursday, December 10.

Some people even thought they saw smoke over Twickenham Stadium and called the fire brigade.

This turned out to be a false alarm. In fact, new grass seeds are being sewn into the turf and special lights are being used to stimulate their fast growth.

Jim Buttar of the RFU must have enjoyed a chuckle after watching everyone ask What the hell is this?

Read more: Firefighters attend as orange glow in the sky is seen across Richmond

Mr Buttar shared a photo of the lighting system on the grass at Twickenham.

Richmond Nub News understands that the lights are regularly turned on and perfect weather conditions on Thursday night allowed the glow to be captured in the clouds.

"This is why!," Mr Buttar said.

"Major light refraction but plenty of warmth to back up the under soil heating. A couple of degrees could mean an extra day on the other side!"

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