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Even as the solar eclipse was mesmerizing millions, astronomers were training their space- and land-based telescopes on a far more violent astrophysical event.
Astronomers thought that all Type Ia supernovas shine with the same brightness, making them incredibly useful cosmic yardsticks. But uncertainty over what causes these explosions has led researchers to reconsider their assumptions.
The newly developed theory of emergent gravity, proposed as an alternative to dark matter, struggles in one of its first trials.