The planet Neptune was first observed by astronomer Johann Gottfried Galle in the night sky of September 23, 01846. Well, it wasn’t until recently that the large blue planet completed its first (roughly) 165-year orbit since the night when Galle first viewed it from the Berlin Observatory. Paul Gilster at Centauri Dreams wrote a thoughtful and interesting post on the event, which occurred on July 12 of 02011. Gilster even includes a brief overview of Neptune’s appearances in science fiction:
H.G. Wells likewise wrote about Neptune in ‘The Star’ (1897), a short story in which the planet is destroyed by a collision with what appears to be a rogue wandering planet from the interstellar deep. The event puts a brilliant new star in Earth’s sky, one that inexorably approaches our planet. Interestingly, the massive new object now gets a gravitational assist from Jupiter, as foreseen by a canny mathematician who forecasts the end of the human race…
To put Neptune’s orbital longevity in perspective, I like to reflect on the fact that it will orbit the sun a mere sixty times in the next 10,000 years.
