From this article
From Google Translate:
Among the eight planets, Mercury, Venus, Earth, Mars, and Saturn could be seen on the earth by ancient humans. Astrology became popular between the Qin and Han Dynasties in ancient China, and the five planets were connected with gods. The silk book "Five-Star Zodiac" unearthed at Mawangdui in Changsha can be regarded as the earliest known astrological work, in which the five stars correspond to the five directions, the five elements, and the five emperors.
東方木，其帝太昊，其丞句芒，其神上為歲星。(Wood corresponds to East)
西方金，其帝少昊，其丞蓐收，其神上為太白。(Metal corresponds to West)
南方火，其帝炎帝，其丞朱明，其神上為熒惑。(Fire corresponds to South)
北方水，其帝顓頊，其丞玄冥，其神上為辰星。(Water corresponds to North)
中央土，其帝黃帝，其丞后土，其神上為填星 (Soil corresponds to Center)
Ancient Chinese observed the five planets and named them 金星, 木星, 水星, 火星, 土星 before they learned about the English names of those planets. We just keep using the existing Chinese names instead of translating the English name into Chinese.
Uranus, Neptune, and Pluto were discovered in modern time, therefore we translated them as 天王星, 海王星, and 冥王星 from English
If we translate Venus, Jupiter, Mercury, Mars, Saturn into Chinese, we might call them 愛神星，神王星，旅神星，戰神星 and 農神星