The sun is not the only source of sun tan as a recent study suggest. As it turned out, some alien sunlight contributes to that golden glow that many aspire to achieve by basking under the sunlight.

On the usual, the body is exposed to "sextillion" photons of light per second but not all of that comes from the Earth's sun but from an alien source beyond the Milky Way galaxy. Although most of the small amounts of energy or photons originate from the Sun, a good number of photons also comes from alien light sources far away from the Earth.

Experts say that a small amount of energy in the form of photons traveled across the Universe but it will take billions of years for the energy tor each the Earth and touch a human skin. For the first time, astronomers were able to measure the light reaching the Earth from the alien source other than the Sun. It was measured over a wavelength range.

Although space radiation is considered deterrent to mankind, only a very small and safe amount reaches the Earth so there is nothing to worry about. A study said that the Earth receives about 10 billion photons per second and it originated outside Milky Way and coming from the deep crevices of the Universe.

"Most of the photons of light hitting us originate from the Sun, whether directly, scattered by the sky, or reflected off dust in the Solar System," astrophysicist professor Simon Driver said in a statement. "However, we're also bathed in radiation from beyond our galaxy, called the extra-galactic background light," Driver added.

Based on the study, the amount  of alien light source that can even cause suntans might sound too much, but in order for the alien sunlight to damage the skin, humans have to be exposed to it for trillions of years before any form of damage appears.

The Earth is also designed to withstand alien sunlight and other types of radiation that helps transform light from alien sources into a less damaging state.

The sun usually gives out 1 sextillion (1,000,000,000,000,000,000,000) of photons per second, according to Seeker. While alien sunlight that reaches the Earth is about 10,000,000,000 photons per square meter per second. Aside from that other light sources that reach the Earth includes leftover from the Big Bang and reflections off dust in the Solar System.