Lunar halo (Moondogs)

A moon dog (or moondog) or mock moon, also called a paraselene[1] (plural paraselenae) in meteorology, is an atmospheric optical phenomenon that consists of a bright spot to one or both sides of the Moon. They are exactly analogous to sun dogs.

Moon dogs are caused by the refraction of moonlight by hexagonal-plate-shaped ice crystals in cirrus or cirrostratus clouds. They typically appear as a pair of faint patches of light, at around 22° to the left and right of the Moon, and at the same altitude above the horizon as the Moon. They may also appear alongside 22° halos.

Moon dogs are rarer than sun dogs because the Moon must be bright, about quarter moon or more, for the moon dogs to be observed. Moon dogs show little color to the unaided human eye because their light is not bright enough to activate the eye’s cone cells.[citation needed]

There are many potential explanations for sightings. We recommend eliminating the most common and mundane before jumping to less probable conclusions or you submit a report.


Object Trackers

Live flight tracking maps are available for monitoring airline traffic and trajectories in real-time or historically around the world.



ADS-B Exchange

Marine Traffic

Space Launches

Planned launches occur regularly all over the globe. These tracks can help identify the potential missions or launches in your area.


Satellite Trackers

Satellite tracking can also be done in real-time with the aid of tracking maps. They are also helpful for tracking Starlink launches.

Heavens Above

Space Weather

There are a number of sites which track solar flares, magnetic storms, and other events which are helpful for eliminating explanations related to astronomic phenomena.

Méprises Du Ciel

French site (with English translations) with resources and examples covering the most commonly observed phenomena and explanations for UFOs.