Planet Comparison- Uranus and Neptune

Planet Comparison Report

Uranus:

Uranus was discovered in 1781 by Sir William Herschel. He at first wanted to name the planet Sidus Georgium which is latin for George’s star after the king of England. Another astronomer Johann Bode advised Herschel against it and suggested instead that he use a name from Greco-Roman mythology like all other planets. So Uranus was given its name which is the father of Saturn.

Uranus is one of the Jovian planets and like the others it has a short rotation period. Uranus’s day is 17.2 hours. Its revolution around the sun however is slightly more than 84 years. It is the seventh planet from the sun at a distance of 1.78 billion miles.

Uranus is about 4 times the diameter of earth at 46,700km. Its mass is 15 times that of earth at 8.68*10 kg. The axial tilt of this planet is one of the most unusual things about it. It is tilted 98 degrees which classifies it as being in retrograde rotation. Uranus is also unique because it has the most inclined magnetic field. The surface magnetic field is 74 percent that of the earth. The surface gravity on Uranus is 8.87 m/s².

The atmosphere of Uranus is thick with a lot of hydrogen, helium, and methane. It has a very low density, the mean density is 1271 kg/m³. Uranus lacks any really significant internal heat source and it mean surface temperature is 58° K.

To date Uranus has been found to have 21 satellites four of which have yet to be named and 11 rings.

News Articles:

From: Regulatory Intelligence Data.

Title: Release 99-47 Huge Spring Storms Rouse Uranus From Winter Hibernation

Date: 03/29/99

NASA’s Hubble Space telescope showed that for the first time seasonal changes on Uranus.

From: ScienceNOW

Title: New moon for Uranus

Date: 05/19/99

A new moon was discovered for Uranus that had previously been overlooked for 13 years. As of 1999 this discovery brought the total of Uranus’s satellites to 18.

Neptune:

Neptune was discovered through a discrepancy in Uranus’s orbit. Uranus’s orbit was not moving how astronomers predicted it would. They could not find an elliptical orbit that fit Uranus’s trajectory. They therefore assumed that there had to be another planet that’s gravitational pull was effecting Uranus. Johann Galle was the first to find Neptune in 1846, even though many before him had mathematically predicted where this new planet would be. The planet was named Neptune and two astronomers who had predicted mathematically where it would be are credited with finding it not Galle.