The biggest thing in the observable universe is estimated to be a vast cosmic structure known as the Hercules-Corona Borealis Great Wall. Discovered in 2013, this colossal wall-like formation spans approximately 10 billion light-years across and contains a mass equivalent to about 10,000 trillion suns. The Great Wall's immense size and density defy easy comprehension, making it one of the most intriguing and awe-inspiring astronomical discoveries in recent times.
