They can also form around artificial lights in very cold weather when ice crystals called diamond dust are floating in the nearby air .
Many halos are positioned near the sun or moon , but others are elsewhere and even in the opposite part of the sky .
others can also form around artificial lights in very cold weather when ice crystals called diamond dust are floating in the nearby air .
Many halos are positioned near the sun or moon , but others are elsewhere and even in the opposite part of the sky .