The discovery of Neptune holds an interesting place in history. After Uranus was discovered, there seemed to be a problem. Astronomers had made calculations based on its position; however, there seemed to be an error as these calculations were at times incorrect. The only explanation was that it was being pulled off its course by something beyond even the boundary of Uranus, which was the farthest known planet at the time.

      In 1843, a young English astronomer and mathematician from Cambridge named John Couch Adams began the quest of finding this unknown force which was pulling on Uranus. With precise accuracy, Adams estimated this “planet” to be one billion miles farther from the sun than Uranus. He completed his work in September of 1845 and sent his findings to Sir George Airy at Greenwich. Sir George Airy was the Astronomer Royal of England and neglected to find this new planet with his telescope; he lacked confidence in Adams and was unwilling to stray from the observatory’s publicly funded work of timekeeping and navigation.

      Meanwhile, a young French mathematician called Urbain J.J. LeVerrier had calculated the position of this new planet by mid-1846. It was only after LeVerrier had published an article about the planet beyond Uranus that Sir George Airy asked Professor James Challis to search for it; Challis found the planet four times without recognizing it. However, Airy’s inaction paid off for the French; LeVerrier sent his findings to the Urania Observatory in Berlin, Germany. Here, Heinrich d’Arrest used the predictions of LeVerrier to find the planet on September 23, 1846. Today both LeVerrier and Adams are credited with discovering Neptune.

      Unable to see with the naked eye, Neptune was found using mathematics before it was even seen with a telescope. After its discovery, it was named Neptune in honor of the Roman sea god. Neptune has eight moons and several rings; it’s atmosphere is made up mostly of hydrogen, helium, methane, and acetylene; it’s surface temperature is about -353 degrees Fahrenheit, or about -214 degrees Celsius. Despite these freezing conditions, Neptune does have an internal heat source. One earth year, or rotation around the sun takes 165 years. However, it completes one revolution approximately every sixteen hours and seven minutes. Neptune has a diameter of 30,800 miles, which is four times that of earth’s; this is approximately the size of Uranus as they are sometimes referred to as twin planets.