Even with modern technology it still is hard to detect all the elements of the vast cosmic space. The hardest celestial bodies to detect are the faint stars with low-mass.
Using microlensing, an astrophysicist from the University of Zurich accomplished such a hard task, observing a low-mass star situated in M22 globular cluster. Therefore, the theories according the existence of faint stars are now proven to be real.
The discovered faint star is believed to have less than a fifth of the mass of our star and it is situated 10 000 light-years away. This discovery was made using the best technical standards available: gravitational microlensing carried out by ESO VLT telescope.

Since the year 2000, scientists theorized that the light can be found in a curved path when near large masses instead of spreading in a straight line (phenomenon called gravitational microlensing); according to the hypotheses, the brightness of such a star can increase exponentially when a big object (in this case, a celestial body) crosses in front of it, acting like a lens. As proved recently, the increased brightness can be observed and studied for several days until the celestial body crosses the faint star.
This discovery has great value for astrophysics, as it redefines the entire structure of globular clusters found in deep space. In the past, the globular clusters’ masses could only be explained through the existence of dark matter, a subject that still remains unproven. Thanks to the discovery of faint stars with low-mass, the overall mass of globular clusters may now be explained with scientific proof, as a faint star can act as a lens within its own globular cluster.
Further observation of the process may reveal new and vital data regarding our understanding of the Universe.
Source: sciencedaily