Astronomy teaches us that celestial bodies like the sun and stars give off their own light. Other bodies like planets or the moon are visible as they reflect sun’s light. But little did we realize that stars reflect some of the light that falls on them too. The fact that all bodies reflect some light is an established phenomenon in physics. However, how stars reflect light is surprisingly under-examined.
This subject was taken up by researchers at the University of New South Wales (UNSW). Spica or Alpha Virginis is a binary star system with an orbital period of four days. Scientists at UNSW used this binary star system to study if stars reflect light off each other.
Polarization of Light Used to Determine Reflected Light
When light travels directly, it is unpolarized. This light oscillates along multiple planes simultaneously. After reflection, these light rays become polarized, and oscillate along a single plane. This property of light can help determine if the light rays are a part of reflected light or not.
The research team thus observed that Spica emanates polarized light waves. This leads to the conclusion that stars reflect some of the light that falls on them, too. However, the amount of reflection is quite poor. For instance, the research shows that the sun reflects only 0.1% of the light falling on it. This concurs with the reflected light model used for the study.
While Spica is a bigger star system, the amount of reflected light only rises by some percentage. This shows that the amount of light reflected from stars is still less than that from other bodies. .
Binary Star Systems to be Studied Further Using Light Reflection of Stars
Scientists also found that this experiment helps them understand stars better. Other systems cannot detect binary star systems,, hence, light reflection will be a key theory.. This study confirms that Spica orbits clock-wise. Consequently, further research can also help determine the mass of binary star systems. Using this research, a detailed study of binary star systems will be possible in the coming years.