Peace Signs Live Wallpaper v1.0
[by Urke]
Requirements: 2.1+
Find your own Âlucky star with Shiny Stars Live Wallpaper!
Enjoy watching little stars
twinkling and floating across your phone screen! Choose the background
color you like the most and create your new favorite live wallpaper!
Perfect live wallpaper for Android!
Interactive background-Tap anywhere on the screen and new stars will appear!
Full support for landscape mode and home-screen switching!
Interactive background-Tap anywhere on the screen and new stars will appear!
Full support for landscape mode and home-screen switching!
Enjoy this lovely, free and useful live wallpaper!
Installation instructions:
Home -> Menu -> Wallpapers -> Live Wallpapers
Home -> Menu -> Wallpapers -> Live Wallpapers
Due to their great distance from the Earth, all stars except the Sun appear to the human eye as shining points in the night sky
that twinkle because of the effect of the Earth’s atmosphere. The Sun
is also a star, but it is close enough to the Earth to appear as a disk
instead, and to provide daylight. Other than the Sun, the star with the largest apparent size is R Doradus, with an angular diameter of only 0.057 arcseconds.
The disks of most stars are much too small in angular size to be
observed with current ground-based optical telescopes, and so
interferometer telescopes are required to produce images of these
objects. Another technique for measuring the angular size of stars is
through occultation. By precisely measuring the drop in brightness of a star as it is occulted by the Moon (or the rise in brightness when it reappears), the star‘s angular diameter can be computed.
Stars range in size from neutron stars, which vary anywhere from 20
to 40 km (25 mi) in diameter, to supergiants like Betelgeuse in the
Orion constellation, which has a diameter approximately 650 times larger
than the SunÂabout 900,000,000 km (560,000,000 mi). However,
Betelgeuse has a much lower density than the Sun.
In astronomy, luminosity is the amount of light, and other forms of radiant energy, a star radiates per unit of time. The luminosity of a star
is determined by the radius and the surface temperature. However, many
stars do not radiate a uniform fluxÂthe amount of energy radiated per
unit areaÂacross their entire surface. The rapidly rotating star Vega, for example, has a higher energy flux at its poles than along its equator.
Surface patches with a lower temperature and luminosity than average
are known as starspots. Small, dwarf stars such as the Sun generally
have essentially featureless disks with only small starspots. Larger,
giant stars have much bigger, much more obvious starspots, and they also
exhibit strong stellar limb darkening. That is, the brightness
decreases towards the edge of the stellar disk. Red dwarf flare stars
such as UV Ceti may also possess prominent starspot features.
Stars always twinkle because theyÂre so far away from Earth that,
even through large telescopes, they appear only as pinpoints. And itÂs
easy for EarthÂs atmosphere to disturb the pinpoint light of a star.
As a starÂs light
pierces our atmosphere, each single stream of starlight is forced by the
atmosphere to zig and zag this way and that. . . . and so stars appear
to twinkle.
ItÂs pretty tough to figure out which objects are stars and which
are planets just by looking for the twinklers vs the non-twinklers. But
if you can recognize a planet in some other way, you might notice the
steadiness of its light by contrasting it to a nearby star.
By the way, if you could see them both stars and planets from outer
space, both would shine steadily. ThereÂd be no atmosphere to disturb
the steady streaming of their light.
WhatÂs more  while itÂs true that, for the most part, planets
donÂt twinkle  you might see them twinkling a little if you spot them
low in the sky. ThatÂs because, in the direction of any horizon,
youÂre looking through more atmosphere than when you look overhead.
Even planets canÂt withstand too much atmosphere, because itÂs the
atmosphere that makes them twinkle!
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