Radiometric dating planets

26-Jan-2019 16:37

In the 16th century, Johannes Kepler noticed a big gap between the orbits of Mars and Jupiter.

He imagined a planet might be there, but he didn’t actually look for it.

Some have been ruled out, but others might have actually existed in the past and may even exist now.

In the early 1800s, astronomers knew of all the major planets in our solar system except Neptune.

After Kepler, many astronomers noticed a pattern in the orbits of the planets.

The relative orbit sizes, from Mercury to Saturn, are approximately 4, 7, 10, 16, 52, and 100.

There’s also a strange factor of four between 12 and 48.

Astronomers began to wonder if there was a missing planet between 12 and 48, at 24—that is, between Mars and Jupiter.

Uranus wasn’t the only planet whose observed motions didn’t jive with predictions. The discrepancy was first observed by French mathematician Urbain Le Verrier, who noted that the low point in Mercury’s elliptical orbit, called the perihelion, was moving around the Sun faster than his calculations said it should.It was a small discrepancy, but additional observations of Mercury convinced him that it was real.He suggested that the discrepancy was caused by an undiscovered planet orbiting inside the orbit of Mercury, which he called Vulcan. Some turned out to be sunspots, but others were made by respectable astronomers and seemed plausible.When Le Verrier died in 1877, he believed that Vulcan’s existence had been confirmed.However, Einstein’s theory of general relativity was published in 1915, and it could properly predict the movements of Mercury.

Uranus wasn’t the only planet whose observed motions didn’t jive with predictions. The discrepancy was first observed by French mathematician Urbain Le Verrier, who noted that the low point in Mercury’s elliptical orbit, called the perihelion, was moving around the Sun faster than his calculations said it should.

It was a small discrepancy, but additional observations of Mercury convinced him that it was real.

He suggested that the discrepancy was caused by an undiscovered planet orbiting inside the orbit of Mercury, which he called Vulcan. Some turned out to be sunspots, but others were made by respectable astronomers and seemed plausible.

When Le Verrier died in 1877, he believed that Vulcan’s existence had been confirmed.

However, Einstein’s theory of general relativity was published in 1915, and it could properly predict the movements of Mercury.

In 1800, he organized several astronomers to perform a systematic search.