Neptune, the Secretive Twin

Neptune has several things in common with its almost-twin, Uranus. It was seen and considered a star by early astronomers (it is invisible to the naked eye), similar to the way Uranus was cataloged as a star before creationist astronomer Sir William Herschel realized Uranus was a planet in 1781. The two planets are apparently similar in size and composition, the blue coloration probably caused by methane. Both have moons that do not quite act the way they should.

Neptune Full Disc, Voyager 2, NASA/JPL
Neptune's identification as a planet is both international and controversial. Astronomers watching Uranus were noticing some oddities in its orbit and asked, "Dude, what's up with that?" Creationist scientist Isaac Newton did some calculations on motion and gravitation, and Newtonian physics indicated that there should be something else up there. Several people went to work on the mathematics, especially John Couch Adams in England and Urbain Le Verrier in France. Both were unaware of each other's work. Some say that Adams was the first to discover Neptune, others stand by Le Verrier because Adams was inaccurate and submitted his work late, no he didn't, yes he did... Le Verrier ultimately was given credit for the discovery of Neptune as a planet. The controversy is occasionally revived even today.

Like other planets and moons in the solar system, Neptune presents problems for evolutionary cosmologists. One of those is the magnetic field, which was accurately predicted by creationist Dr. Russell Humphreys. Another frustration to evolutionary thinking is that its large moon Triton has a retrograde orbit (opposite of Neptune's rotation), unlike other large moons. Of course, these problems for "deep time" cosmologists are not a problem for biblical creationists.

The best way to find out about Neptune is to go up there and look. It is 2.7 billion miles (4.3 billion km) away at its closest point, why not? It took Voyager 2 twelve years to get there.
At an average solar distance of 2.8 billion miles (over 30 times farther out than Earth), Neptune is the most distant planet of the solar system. This makes it a difficult world to study. It is too faint to be seen with the unaided eye under any circumstances but can be detected in binoculars and is easily visible in a backyard telescope. In fact, it is likely that Galileo saw Neptune hundreds of years before its official discovery. This was purely by accident during one of his routine observations of Jupiter. On January 4, 1613, Jupiter passed directly in front of Neptune for several hours. While Galileo’s telescope was meager by today’s standards, Neptune would certainly have been visible for many nights before and after this event, though it would have been indistinguishable from background stars. Today, Neptune appears as a tiny, solid-blue sphere in even the most powerful Earth-based telescopes. Atmospheric features, such as white clouds, are occasionally visible—but just barely.
You can read the rest of "The Solar System: Neptune", in context.