Two supernovas in a galaxy, and one that's so utterly far away that we see it as it was 10 billion years ago, could be vital in helping reveal the expansion rate of the universe. This is a measurement that has rather created some tension among the scientific community.
The galaxy and the two supernovas were imaged by the Hubble and James Webb space telescopes. The galaxies are made visible by the power of gravitational lensing — a phenomenon in which large amounts of mass, such as what's found in a galaxy cluster, can warp space into a "lens" shape that can then magnify and distort the light of more distant galaxies.
