The ninth planet of the solar system was 13 ______ not long ago. It happened in 1930. Scientists had been hunting for the planet for a 14 ______time. They had calculated its probable position but there was no proof that the planet really 15 ______. It was too 16 ______ away for the telescopes of that time to find it. It’s worth mentioning that the first photos of the planet were taken by a very young researcher. He was only twenty-four and had no formal education in astronomy. However, he was deeply involved in the search for the ninth planet. The planet at the edge of the 17 ______ system was called Pluto, after the Roman god. The name for the planet was 18 ______ by an 11-year-old British girl.