Earlier this month, astronomers were excited to discover three supernovas in far-off galaxy, with a huge galaxy cluster sandwiched between us and them. The galaxies’ enormous gravity magnified the light of the exploding stars, an effect called gravitational lensing.
Since these were a particular type of exploding star, they can be used as cosmic yardsticks. That means astronomers were able to check the prescription, as it were, of the gravitational lenses. This is important for measuring the structure of the Universe (including dark matter), and for making sure astronomers’ measuring tools are calibrated correctly.
via DVICE
Image: Wikipedia
