Comet Shoemaker–Levy 9 rarity: one post-impact study estimated that comets in diameter impact the planet once in approximately 500 years and those in diameter do so just once in every 6,000 years. There is very strong evidence that comets have previously been fragmented and collided with Jupiter and its satellites. During the Voyager missions to the planet, planetary scientists identified 13 crater chains on Callisto and three on Ganymede, the origin of which was initially a mystery. Crater chains seen on the Moon often radiate from large craters, and are thought to be caused by secondary impacts of the original ejecta, but the
Social media and television a sign of superficiality." Interactive media such as Amazon's Alexa and Apple's Siri have enabled computers to interact with people in human-like ways. "Computers, in the way that they communicate, instruct and take turns interacting, are close enough to humans that they encourage social responses. The encouragement is necessary for such a reaction need not be much. As long as there are some behaviors that suggest a social presence, people will respond accordingly." The exponential growth in the number of social media users between 2006 and 2016 has impacted how television shows are marketed. As well, the huge increase in