Solar System Exploration: Solar System 101: Homework Helper

HOMEWORK HELPER

The Tilted Planet
Uranus is the only giant planet whose equator is nearly at right angles to its orbit. A collision with an Earth-sized object may explain the unique tilt. Nearly a twin in size to Neptune, Uranus has more methane in its mainly hydrogen and helium atmosphere than Jupiter or Saturn. Methane gives Uranus its blue tint.

Extreme Facts

Say What? Uranus is the only planet with a name sure to elicit giggles. The proper way to say the name is YOOR--un--nus. It was almost named "Georgium Sidus" to honor an English king, but tradition prevailed and in 1850 the planet got its frequently mispronounced mythological name.

A Long, Dark Winter Uranus' unique sideways rotation makes for weird seasons. The planet's north pole experiences 21 years of nighttime in winter, 21 years of daytime in summer and 42 years of day and night in the spring and fall.

Is That Planet Flirting? Uranus' rings were discovered by accident. Two teams were set up to watch a bright star pass behind Uranus -- a way to peek at the planet's atmosphere -- and were surprised when the star unexpectedly blinked out. Nine of Uranus's rings caused the star to wink at them as each ring in turn blocked the light of the star.

Shakespearian Satellites Uranus' moons get their names from classic literature, not mythology. Among the moons orbiting Uranus, you will find Shakespeare's star-crossed lover Juliet of "Romeo and Juliet," unfortunate Ophelia from "Hamlet" and that mischievous fairy Puck from "A Midsummer Night's Dream."

Quick Study Only one spacecraft has visited distant Uranus. After traveling more than 3 billion km (1.8 billion miles) in nine years, NASA's Voyager 2 gathered much of its critical information about the mysterious planet in a scant six hours.

Long Distance Upgrade Think upgrading software on your computer is a pain? Try doing it from billions of kilometers away. Voyager 2's mission controllers pulled off a long- distance upgrade in 1986 to enable the spacecraft to send back sharp pictures taken at high speed in faint sunlight -- only 1/400th of the light we see on Earth.

Retro Planet The sun rises in the west and sets in the east. Wait -- that does not sound right. On Earth you would be correct, but not on Uranus. Uranus is one of two planets (the other one is Venus) that rotate in an opposite direction (retrograde) from the other planets in our solar system. This means that on the planet Uranus the sun appears in the morning on the western horizon and then sets in the east.

A New World Uranus is pretty far out -- so far out that it was unbeknownst to people until the year 1781. William Herschel's discovery of the planet Uranus was the first discovery of a planet in the modern age and through the use of a telescope.

Sideswiped Uranus is the only planet known to rotate on its side. Uranus' odd rotation may be the direct result of a collision with a planet-sized body early in the planet's history.

Who You Calling Little? Even though Uranus and Neptune are much smaller than our solar system's two other giant gas planets, you could still pack nearly 60 Earths inside each.

Say What? Uranus is the only planet with a name sure to elicit giggles. The proper way to say the name is YOOR--un--nus. It was almost named "Georgium Sidus" to honor an English king, but tradition prevailed and in 1850 the planet got its frequently mispronounced mythological name.

A Long, Dark Winter Uranus' unique sideways rotation makes for weird seasons. The planet's north pole experiences 21 years of nighttime in winter, 21 years of daytime in summer and 42 years of day and night in the spring and fall.

Is That Planet Flirting? Uranus' rings were discovered by accident. Two teams were set up to watch a bright star pass behind Uranus -- a way to peek at the planet's atmosphere -- and were surprised when the star unexpectedly blinked out. Nine of Uranus's rings caused the star to wink at them as each ring in turn blocked the light of the star.

Shakespearian Satellites Uranus' moons get their names from classic literature, not mythology. Among the moons orbiting Uranus, you will find Shakespeare's star-crossed lover Juliet of "Romeo and Juliet," unfortunate Ophelia from "Hamlet" and that mischievous fairy Puck from "A Midsummer Night's Dream."

Quick Study Only one spacecraft has visited distant Uranus. After traveling more than 3 billion km (1.8 billion miles) in nine years, NASA's Voyager 2 gathered much of its critical information about the mysterious planet in a scant six hours.

Long Distance Upgrade Think upgrading software on your computer is a pain? Try doing it from billions of kilometers away. Voyager 2's mission controllers pulled off a long- distance upgrade in 1986 to enable the spacecraft to send back sharp pictures taken at high speed in faint sunlight -- only 1/400th of the light we see on Earth.

Retro Planet The sun rises in the west and sets in the east. Wait -- that does not sound right. On Earth you would be correct, but not on Uranus. Uranus is one of two planets (the other one is Venus) that rotate in an opposite direction (retrograde) from the other planets in our solar system. This means that on the planet Uranus the sun appears in the morning on the western horizon and then sets in the east.

A New World Uranus is pretty far out -- so far out that it was unbeknownst to people until the year 1781. William Herschel's discovery of the planet Uranus was the first discovery of a planet in the modern age and through the use of a telescope.

Sideswiped Uranus is the only planet known to rotate on its side. Uranus' odd rotation may be the direct result of a collision with a planet-sized body early in the planet's history.

Who You Calling Little? Even though Uranus and Neptune are much smaller than our solar system's two other giant gas planets, you could still pack nearly 60 Earths inside each.