Kanji From Zero! 1: Proven Techniques to Learn Kanji with Integrated Workbook

We have chosen to include recently discovered planets such as Eris (2005) and Sedna (2003) in order to have an accurate list. Also, it's interesting to see that the more recently discovered planets do not have kanji assigned to them. Despite Ceres being discovered in 1801, even before Neptune, it doesn't have kanji. In China, Ceres is written as 穀神星, however Japan never adopted a kanji for this dwarf planet (asteroid).

Unfortunately, for kanji lovers such as myself, new Japanese words are often "borrowed" from English and are only written in katakana. These borrowed words are called 外来語 (がいらいご), which ironically, is written in kanji.