An optical illusion is a visual phenomenon where our perception of an image differs from objective reality. This image is perceived as a visual impression of a swirling tunnel or vortex effect. These ...

The last time Texas experienced a “polar vortex effect” was last winter, when a cold front brought frigid temperatures and wind chills down to -15 degrees. David Montesino dmontesino@star-telegram.com ...

Researchers have found that a swirling water vortex can force opposing waves to form rotating lines of stillness across an ...