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An example of the scintillating grid illusion. Dark dots seem to appear and disappear at intersections. The scintillating grid illusion is an optical illusion, discovered by E. and B. Lingelbach and M. Schrauf in 1994. [2]
The overlapping black arc segments appear to form a spiral; however, the arcs are a series of concentric circles. Gravity hill: Grid illusion: Any kind of grid that deceives a person's vision. The two most common types of grid illusions are the Hermann grid illusion (1870) and the scintillating grid illusion (1994).
The bumps on a toad are not warts and cannot cause warts on humans. Humans cannot catch warts from toads or other animals; the bumps on a toad are not warts. [314] Warts on human skin are caused by human papillomavirus, which is only known to affect humans. [315] Cracking one's knuckles does not cause osteoarthritis. [316] [317]
Astronauts who had recently returned from space missions to the Hubble Space Telescope, the International Space Station and Mir Space Station reported seeing the LF under different conditions. In order of decreasing frequency of reporting in a survey, they saw the LF in the dark, in dim light, in bright light and one reported that he saw them ...
White cells are larger than red blood cells and can be larger than the diameter of a capillary, so must deform to fit. As a large, deformed white blood cell goes through a capillary, a space opens up in front of it and red blood cells pile up behind. This makes the dots of light appear slightly elongated with dark tails.
American astronaut Marsha Ivins demonstrates the effects of microgravity on her hair in space. The effects of spaceflight on the human body are complex and largely harmful over both short and long term. [1] Significant adverse effects of long-term weightlessness include muscle atrophy and deterioration of the skeleton (spaceflight osteopenia). [2]
In many cultures, several pareidolic images of a human face, head or body are recognized in the disc of the full moon; they are generally known as the Man in the Moon. The images are based on the appearance of the dark areas (known as lunar maria) and the lighter-colored highlands (and some lowlands) of the lunar surface.
A random-dot stereogram (RDS) is stereo pair of images of random dots that, when viewed with the aid of a stereoscope, or with the eyes focused on a point in front of or behind the images, produces a sensation of depth due to stereopsis, with objects appearing to be in front of or behind the display level.