Twenty-six weird tales and unexplained phenomena from ancient times to today
Aliens
On October 11, 2018, strange lights over northern China provoked alien invasion fears, although experts theorized missile or “high-altitude aircraft” trails

(VCG)
Baigong
Centuries-old iron pipes discovered in 2002 on Mount Baigong, Qinghai province, suggest highly advanced engineering know-how with their formation, symmetry, and composition.