Search results
Results from the WOW.Com Content Network
In human visual perception, the visual angle, denoted θ, subtended by a viewed object sometimes looks larger or smaller than its actual value. One approach to this phenomenon posits a subjective correlate to the visual angle: the perceived visual angle or perceived angular size. An optical illusion where the physical and subjective angles ...
The moving-cluster method relies on observing the proper motions and Doppler shift of each member of a group of stars known to form a cluster. The idea is that since all the stars share a common space velocity, they will appear to move towards a point of common convergence ("vanishing point") on the sky. This is essentially a perspective effect.
Perspective, relative size, occultation and texture gradients all contribute to the three-dimensional appearance of this photo. Depth perception is the ability to perceive distance to objects in the world using the visual system and visual perception. It is a major factor in perceiving the world in three dimensions.
Photometry (astronomy) In astronomy, photometry, from Greek photo- ("light") and -metry ("measure"), is a technique used in astronomy that is concerned with measuring the flux or intensity of light radiated by astronomical objects. [1] This light is measured through a telescope using a photometer, often made using electronic devices such as a ...
The Golovin–Sivtsev table ( Russian: Таблица Головина-Сивцева) is a standardized table for testing visual acuity, which was developed in 1923 by Soviet ophthalmologists Sergei Golovin and D. A. Sivtsev. [1] In the USSR, it was the most common table of its kind, and as of 2008 its use is still widespread in several post ...
Ultimately, however, it appears that the size of a patch of cortical tissue in visual area V1 that processes a given location in the visual field (a concept known as cortical magnification) is equally important in determining visual acuity. In particular, that size is largest in the fovea's center, and decreases with increasing distance from there.
It contains Ursa Major and the Hyades star cluster, among others. The Local Bubble also contains the neighboring G-Cloud, which contains the stars Alpha Centauri and Altair. In the galactic context, the Local Bubble is a small part of the Orion Arm, which contains most stars that we can see without a telescope.
Stellar age estimation. Young star ejecting two jets of energised gas [1] Various methods and tools are involved in stellar age estimation, an attempt to identify within reasonable degrees of confidence what the age of a star is. These methods include stellar evolutionary models, membership in a given star cluster or system, fitting the star ...