According to a recent report, the Indian Army monitored two unidentified objects for six months, suspecting that they could have been Chinese drones — before learning they were actually just planets. The Telegraph reports that the army started tracking the two objects near the border of India and China back in August of 2012, noting certain patterns of behavior: one object appeared regularly at around 6PM local time and stayed visible until 5AM the following morning, while the other was visible between 4AM and 11AM.
By February of this year, 329 sightings had been logged, with the objects appearing to cross over into Indian territory 155 times. Given the escalating tensions and concern about unmanned aerial vehicles in the region, astronomers from the Indian Institute of Astrophysics were brought in. "Our task was to determine whether these unidentified objects were celestial or terrestrial," Tushar Prabhu, a senior astronomer with the Institute, told The Telegraph. Soldiers measured the horizontal angle and vertical elevation of the objects over a period of several days, after which the data was processed by the Institute. Tracking the motion and timing of the appearances led to the conclusion that the soldiers had actually been observing Jupiter and Venus all along.
While the mistake may seem absurd on its face, according to the astronomers the confusion wasn't unwarranted. Due to the altitude, both planets would have been the brightest objects in the sky, and as they rose in the east they would have been perceived by the soldiers to be moving across the border as observed.