What structure, extending over 1.37 billion light-years and mapped via visible galaxies, historically served as a major benchmark for cosmic size before the Quipu's confirmation?
Sloan Great Wall
Prior to the identification and measurement of gargantuan structures like the Quipu using Gamma-Ray Bursts, astronomers relied on surveys mapping visible galaxies to gauge the limits of cosmic architecture. The Sloan Great Wall was a significant milestone in this area, recognized for its immense scale, which stretches across approximately 1.37 billion light-years. This structure represented the largest known concentration of matter identified through traditional visible galaxy mapping efforts for a considerable period. However, visible surveys are inherently limited by how far back in time they can see based on observable light, potentially obscuring fainter, more diffuse large-scale structures that the GRB method later revealed.

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