For nearly five decades, NASA’s Voyager 1 and 2 spacecraft have been instrumental in exploring the solar system’s outermost edge. As they ventured into the boundary where the Sun’s influence meets interstellar space, they uncovered a remarkable phenomenon: a blazing “wall of fire.” This thin, superheated region, reaching temperatures up to 50,000 Kelvin, marks the heliopause, the transition zone where solar wind pressure is balanced by the pressure of the interstellar medium.