World’s Largest Map of Space Offers Clues on Dark Energy
A new chart of millions of galaxies across 11 billion years of cosmic history helps to answer some of the biggest cosmological questions.
The maps we create are crucial for studying the physics that drives cosmic history. In July 2020, a 20-year project we worked on called the Sloan Digital Sky Survey produced the largest map of the cosmos ever made. It includes our immediate surroundings, the farthest reaches of space, and everything in between. This three-dimensional chart contains the positions of four million galaxies laid out like signposts over many billions of light-years, stretching back in time to some of the earliest epochs of the universe.
The map shows that galaxies are not distributed randomly. Instead they cluster in patterns: long filaments and two-dimensional sheets of galaxies in some areas; dark voids containing few galaxies in others. Scientists believe these patterns emerged before the galaxies were born, starting less than one billion years after the big bang. By mapping as much of cosmic history as possible, we can record the growth of these patterns and deduce the fundamental laws that guided their evolution. This atlas of galaxies provides crucial information in the quest to understand some of the biggest mysteries in physics, such as the geometry of the universe and the nature of the dark energy driving the accelerating expansion of space...