The Voyager spacecraft, launched in 1977, are the farthest human-made objects from Earth, traveling over 12 billion miles at speeds of 38,000 mph.

Originally tasked with studying the outer planets, they now journey into interstellar space, providing insights into the solar system’s boundary.

Both spacecraft encountered a “wall of fire” at the heliosphere’s edge, where temperatures reached up to 90,000°F, marking the transition from solar wind to the interstellar medium.

Voyager 1 crossed the heliopause in 2012, followed by Voyager 2 six years later, revealing that the heliosphere is teardrop-shaped and influenced by the solar system’s motion through space, Jalopink has reported.

Their journey has confirmed theories about solar wind limits, heliosphere shape, and the conditions at the edge of our solar system.