Talk:Uranus (planet)

Natural satellites

Re: "Uranus has twenty-seven satellites, all named after Shakespearean characters, the largest being Titania, Oberon, Umbriel, Ariel and Miranda."

Nice addition Ro. The very thing that makes it more interesting to read.--Thomas Simmons 16:58, 23 November 2007 (CST)

Thanks - Ro Thorpe 14:52, 24 November 2007 (CST)

Seasons on Uranus

In discussing the seasons on Uranus, the article references the NASA Education section of the NASA web site (article on "Planetary seasons" at http://www.nasa.gov/audience/foreducators/postsecondary/features/F_Planet_Seasons.html). The full passage relating to seasons on Uranus reads:

"Uranus, like Earth, has a nearly circular orbit, so it remains at the same distance from the Sun throughout its long year. But the axis of Uranus is tilted by 82°. This causes 20-year-long seasons and unusual weather, although one thing that is for certain is that it is always cold. For nearly a quarter of the Uranian year (equal to 84 Earth years), the Sun shines directly over each pole, leaving the other half of the planet plunged into a long, dark winter. Uranus is a ball of mostly hydrogen and helium. Absorption of red light by methane in the atmosphere gives the planet its bluish color. Early visual observers reported Jupiter-like cloud belts on the planet, but when the Voyager 2 spacecraft flew by in 1986, Uranus appeared virtually featureless. The Northern Hemisphere of Uranus is just now coming out of the grip of its decades-long winter. As the Sunlight reaches some latitudes for the first time in years, it warms the atmosphere and triggers gigantic springtime storms comparable in size to North America with temperatures of 300° below zero. By the year 2007, the Sun will be shining directly over Uranus' equator, which will produce more evenly distributed Sunlight and the ability to see features on Uranus."

The section of the CZ article on Uranus regarding the seasons read (before I removed it):

"Uranus has a nearly circular orbit with the result that it is at almost the same distance from the sun throughout the year. Since the axis of Uranus is tilted by 82°, Uranus has 20-year-long seasons and it is always cold. For almost one-quarter of the Uranian year (about 84 Earth years), the Sun shines directly over each pole, leaving the other half of the planet in the dark causing a long winter. While its polar orientation switches back and forth as it orbits the sun, as the Sunlight reaches some latitudes for the first time in years, it warms the atmosphere and triggers gigantic springtime storms over areas nearly the size of North America with temperatures of 300° below zero. [8][9]"

I removed this passage because, in my opinion, it is too closely derivitive from the NASA article (and thus not original).

I will re-write the passage relating to seasons on Uranus. In doing so, it should not be necessary to reference any "atuhority" article (though that can be done). Instead, it is only necessary to understand the rotational characteristics of the planet and its axis of inclination as it circles the Sun.

James F. Perry 18:07, 26 November 2011 (UTC)

Seasonal appearances (and axial tilt)

I hope the explanation of the seasonal appearances is clear. A diagram would have helped.

The axis of rotation of Uranus is variously listed as 98 degrees or 82 degrees (in fact, prior to my recent edits, it was listed both ways in the article). When the planet is tilted almost on its side as Uranus is, it can be a question as to which pole you are referring to. The "north" pole is determined by the right hand rule using the direction of rotation of the planet (the planet would appear to be rotating counter-clockwise when looked upon from above the north pole) and it is this pole and its tilt with respect to the North Ecliptic Pole which determines the angle. In any case, my copy of the Encyclopedia of Astronomy (ed. Patrick Moore) lists the "inclination of the equator to the orbit" as 97 degrees, 52 minutes. James F. Perry 02:33, 27 November 2011 (UTC)