In 1936, Albert Einstein penned a research paper on his theory of relativity predicting that the weight of stars can be measured by the bending of passing light, a phenomenon now called gravitational microlensing that scientists have since observed.
But in that paper, published in the journal “Science,” Einstein said, “Of course, there is no hope of observing this phenomenon directly,” largely because stars are so far apart from one another.
Contrary to Einstein’s statement, astronomers studying the skies with NASA’s Hubble Telescope did just that this week when they directly measured the mass of a white dwarf star using his gravitational lensing theory.
The team, led by astronomer Kailash Sahu of the Space Telescope Science Institute, directly measured the mass of the dwarf star Stein 2051B by putting it on an interstellar balance scale.
The scientists observed Stein 2051B and its partner star, Stein 2051A, with the Hubble Space Telescope.
According to Gizmodo, they measured shifts in light as Stein 2051B passed in front of light sources behind it and behind other random stars, gathered the data and used Einstein’s lensing equation to determine the star’s mass.
Read more here.
