19. The hottest planet
Since the mercury is the closest planet but it is not the hottest of all. Mercury is only hot during day times since it has no atmosphere of its own.
At night, the temperature falls up to -180 C. Venus is the hottest planet in the solar system.
20. Astronauts are placed in quarantine
It was previously believed that the moon contains some deadly pathogens due to which astronauts were placed in quarantine after every space voyage.
But after Apollo 14 returned safely, it was confirmed that moon contains no deadly diseases and they were not placed in quarantine.
