Cheryl Costa, one of the book’s authors, explained that the prevalence of UFO sightings does not say as much about the objects themselves as much as it says about the observers. “[The sightings] are about when observers are available to be outside in nice weather, and whether they have leisure time,” Costa said in an interview with 24/7 Wall St.
The states with the most UFO sightings, and the times of the year where such reports peak, both reflect the greater likelihood of observing the sky.
In Northern states with cold winters, sightings increase dramatically during summer months when more residents are spending their leisure time outdoors. During February in Minnesota, for example, only 69 UFO sightings have been reported since the beginning of the 21st century. In August, there are four times as many reports, at 284 sightings.
Alaska is a notable exception to seasonal trends across the North. Despite large variance in temperature between winter and summer months, sightings actually increase in Alaska during the winter and fall seasons compared to warmer months.
Of the dozens of shapes and types of sightings reported, the most commonly reported UFO appears as a light, which accounts for 13% of all sightings in the data set.
Costa explained that sightings are easier to see at night, which is much longer in Alaska during the winter months. At the summer solstice in Fairbanks, Alaska, the sun is up for more than 21 hours a day, while there are only four hours of sunlight at the winter solstice. Therefore, despite fewer residents out in winter, there are more UFO sightings during these darker months.
By comparison, UFO sighting levels are relatively flat during the year in Southern states, where weather and daylight conditions are also relatively consistent.
The history and culture of an area, which may influence how likely residents are to report a sighting, may further account for the variance between states. Costa noted that people in parts of New Mexico and California continue to share and discuss historic UFO sightings. For example, The Battle of Los Angeles, the name of the famous 1942 incident often cited by some conspiracy theorists as evidence of an alien visit, took place in LA County. The county, one of the most populated U.S. counties, is also home to the most UFO sightings of any county in California.
UFO sighting levels depend on not just the presence of unrecognizable objects, but also on the likelihood of actually reporting such observations. Nationwide, reports of UFO sightings spiked at the turn of the century for two primary reasons: first, the significant increase in broadband internet access made reporting considerably easier, making reporting considerably easier; and second, after the attacks on September 11, 2001 U.S. citizens were strongly encouraged to report everything they saw. “They said report what you see and this is what people said they saw,” Costa noted.