Search results
Results from the WOW.Com Content Network
Red Moon is a free software [1] application for the Android operating system, designed to filter blue light from the device's display, helping reduce eye strain during night-time use and disruption of sleep patterns.
minimum brightness during transits. −2.94: planet Jupiter: seen from Earth maximum brightness [42] −2.94: planet Mars: seen from Earth maximum brightness [42] −2.5: Faintest objects visible during the day with naked eye when Sun is less than 10° above the horizon: −2.50: new moon: seen from Earth minimum brightness −2.50: planet ...
Luminous flux is the total amount of light coming from a source, such as a lighting device. Luminance, the original meaning of brightness, is the amount of light per solid angle coming from an area, such as the sky. The table below shows the standard ways of indicating the amount of light.
Because Solar System bodies are illuminated by the Sun, their brightness varies as a function of illumination conditions, described by the phase angle. This relationship is referred to as the phase curve. The absolute magnitude is the brightness at phase angle zero, an arrangement known as opposition, from a distance of one AU.
It affects the results in a brightness-limited survey, where stars below a certain apparent brightness cannot be included. Since observed stars and galaxies appear dimmer when farther away, the brightness that is measured will fall off with distance until their brightness falls below the observational threshold.
When the Sun drops more than 18° below the horizon, the sky generally attains its minimum brightness. Several sources can be identified as the source of the intrinsic brightness of the sky, namely airglow, indirect scattering of sunlight, scattering of starlight, and artificial light pollution.
In addition to this brightness decrease from increased distance, there is an extra decrease of brightness due to extinction from intervening interstellar dust. [18] By measuring the width of certain absorption lines in the stellar spectrum, it is often possible to assign a certain luminosity class to a star without knowing its distance. Thus a ...
Photometry is a branch of optics that deals with measuring light in terms of its perceived brightness to the human eye. [1] It is concerned with quantifying the amount of light that is emitted, transmitted, or received by an object or a system.