A halo, a striking atmospheric optical display reminiscent of a soft glow encircling a bright light, was observed over Moscow on Friday the sixth of December, noted by a leading specialist from the Phobos weather centre. The sight drew attention from local observers who described a luminous ring that seemed to hover in the cold winter air. The phenomenon offers a vivid reminder of how light and ice can collaborate to create unexpected wonders in the sky. Attribution: Phobos Weather Centre.
A halo arises when sunlight is refracted through countless tiny ice crystals suspended in high-altitude clouds. On very cold winter days these conditions occur with notable frequency, especially when clouds extend between roughly six thousand and ten thousand meters above the ground. When sunlight enters these randomly oriented crystals, it bends and disperses, producing a circular band around the Sun or, in some cases, around its apparent twin in the sky. This optical effect is most visible from clear vantage points and under specific lighting angles, offering a rare glimpse into the physics of Earth’s atmosphere. This description aligns with analyses from the Phobos weather centre, which emphasizes the role of ice crystal geometry and atmospheric layering in forming halos.
Residents of Moscow witnessed a rare weather event described as two suns appearing in the sky over the city. In meteorological terms, experts classify this as a parhelion, a type of halo that presents a secondary bright image at a short distance from the real Sun. The second light source can be striking enough to be mistaken for a second solar disk, particularly when the primary Sun is partially obscured by cloud cover. Similar light-guiding phenomena can also occur near the Moon, known in some observations as paraselene. These light effects reinforce the delicate interaction between sunlight, ice crystals, and the observer’s point of view, transforming the usual winter sky into a momentary spectacle. This explanation draws on established research from atmospheric science and observations reported by the Phobos weather centre.