What is the significance of the Einstein Ring discovered by the Euclid telescope?

The Einstein Ring discovered using the European Space Agency's Euclid telescope provides a unique opportunity to test Einstein's general theory of relativity. This exceptionally bright ring was formed as light from a distant galaxy was bent by a closer lensing galaxy. Researchers can measure the lensing galaxy's mass in two ways: by analyzing light bending and by observing stellar velocity. When calculated, the mass was slightly higher than expected based on visible stars, potentially indicating dark matter clustering at the galaxy's center. This discrepancy offers valuable insights into gravitational models and dark matter distribution.