'13.8 billion years unraveled': Hubble's discovery set the stage for the biggest mystery yet

Produced by: Mohsin Shaikh

Star Puzzle

The early 20th century left astronomers grappling with the mystery of spiral nebulae. Were they part of the Milky Way or entire galaxies on their own? Edwin Hubble set out to answer this cosmic riddle.

Credit: ESA/Hubble & NASA, ESO, J. Lee and the PHANGS-HST Team

Light Shift

Vesto Slipher's observations of redshifted light revealed that spiral nebulae were moving away from Earth, hinting at a much larger universe than previously imagined.

Credit: NASA

Cepheid Breakthrough

Hubble used Cepheid variable stars to calculate the distance to Andromeda. His discovery, over 2 million light-years away, confirmed that spiral nebulae were galaxies beyond the Milky Way.

Cosmic Expansion

Hubble’s work showed galaxies moving apart, leading to the groundbreaking realization that the universe is expanding. This became the foundation for the Big Bang theory.

Shapley’s Loss

Harvard astronomer Harlow Shapley, once a proponent of a smaller universe, famously lamented Hubble’s findings as “the letter that destroyed my universe.”

Representative pic

Hubble’s Legacy

The Hubble Space Telescope, launched in 1990, honored Edwin Hubble's pioneering work. It has since expanded our view of the cosmos, capturing stunning images and refining the universe’s age.

Dark Energy

Hubble’s telescope revealed the universe’s accelerating expansion, driven by the mysterious force of dark energy. Scientists are still working to unravel its secrets.

Representative pic

Distance Ladder

Hubble’s discovery of V1 laid the foundation for the cosmic distance ladder, enabling astronomers to measure distances to far-flung galaxies with precision.

Representative pic

New Frontiers

Future missions like the Roman Space Telescope aim to deepen our understanding of dark energy and build on Hubble’s legacy of cosmic exploration.

Cosmic Perspective

Hubble’s discovery forever changed humanity’s view of itself. The Earth, once thought central, was revealed as a tiny part of an immense, humbling universe.