2 green comets shine bright. How to spot them in the night sky

Two bright green comets streak across the sky and are visible to skywatchers in the Northern Hemisphere. Both originate in the outer limits of our solar system. Comet Lemmon will make its closest contact with Earth on or around Tuesday. To spot the pair, go outside just after sunset and look north for Comet Lemmon near the horizon. Comet SWAN is moving away from the sun and will also be near the horizon, but to the southwest. Comets appear green because of gases escaping from their surface. From Earth, they will look like gray, fuzzy spots.