The sky is suddenly purple in Arizona

Lights from a marijuana farm in Arizona, USA have spread across the sky, causing many people to be concerned about light pollution but there are also many people interested in it.

Strange purple light from a medical marijuana farm filled the sky of Snowflake, Arizona, USA on a foggy morning on January 10, CNN reported.

Cara Smith captured the scene around 6:30 am on January 10 on her way to work to Copperstate Farms, Arizona's largest medical marijuana provider.

Ms Smith's home is 3 km west of the farm and she says the light is often invisible from her home.

"There was always a purple light there, but it usually didn't glow in the sky like this," she told CNN. "It was snowing that morning. There was still a lot of fog and clouds."

A photo of the purple light of a farm needed by Ms. Cara Smith.(Photo: CNN).

Snowflake is located in Navajo County, Arizona, 280 km northeast of Phoenix and 80 km southwest of Petrified Forest National Park.

Navajo County posted Smith's photo on his Facebook page and the photo received many comments from the public.

Some people complain about light pollution caused by lights, while others say that the light is very beautiful.

The Copperstate farm has more than 160,000 square meters of greenhouses - the equivalent of 30 football fields - that incorporate red and green lights at night to help grow crops, according to the company's spokesperson.

From a distance, the light seemed to be purple. However, often the light will not be so strong as the photo Ms. Smith took.

The water droplets in the low-level fog reflected the light and made it spread throughout the sky.

The farm is producing 70 strains of marijuana, another 40 are under development and have been planted since 2017.

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