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Uranus is the seventh planet from the Sun

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and the third-largest planet in the solar system.

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It also may have the coldest interior,
emitting far

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less heat than its counterparts
Jupiter, Saturn and Neptune.

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It is known as an “ice giant”
because it contains more ices,

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including water, methane, and ammonia
than Jupiter or Saturn.

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And while NASA's learned a great deal
about this planet over the last

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three decades, there's a lot more waiting
to be discovered.

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Back in 1986,

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NASA's Voyager 2 spacecraft flew by Uranus,

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making it the first and only spacecraft
to visit this distant planet.

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Previous observations showed
that Uranus has a unique tilt of its axis,

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so it rotates almost on its side, causing
its poles to actually face the Sun.

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No other planet in our solar
system has this feature.

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In its quick sprint past Uranus, Voyager discovered

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ten new moons orbiting the planet
that had not been seen before.

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And in the decades
since, even more have been found.

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During its encounter, Voyager
also saw new faint rings

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and explored the complex magnetosphere.

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Voyager only briefly viewed
the planet's five major moons:

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Ariel, Miranda, Titania, Oberon and Umbriel.

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These moons have a wide variety
of terrains and geological features,

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some of which indicate possible subsurface
oceans.

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Small Miranda has chaotic terrain,
with deep canyons

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and tall mountains,
but is likely now frozen solid.

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Ariel appears to have the youngest surface
with few impact craters.

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While Titania has a very old surface,

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the lack of large craters and
presence of a large canyon system

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may indicate ancient resurfacing.

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Oberon is also covered with craters
and has valleys and large mountains.

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Umbriel’s surface is the darkest of the Uranian moons

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and it sports a strange polar ring.

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The origin of this ring
is still a mystery,

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but scientists believe that
it may have been formed by an icy impact.

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Since Voyager, ground based telescopes

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and the Hubble Space Telescope

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have played the leading role
in our understanding of Uranus.

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Since 1992, Hubble has watched the slowly
changing Uranian seasons,

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including changes in its unusual pale
blue color and polar hazes.

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Telescopes have also revealed
that Uranus has a complex weather system

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with massive storms
that can last for months or even years,

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with wind speeds over 500 miles per hour.

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The ongoing search for ocean worlds
and life beyond Earth

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makes Uranus an exciting target
for the James Webb Space Telescope

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and for future up close exploration.

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New data will help
scientists to understand the formation

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and evolution of Uranus, as well as its
moons and rings, and provide clues

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as to whether liquid water may reside
beneath their icy crusts.

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The fascinating properties of this planet,

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discovered in just the span of a few decades,

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reveal that unlocking mysteries here

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can help scientists learn, even more about
our solar system, and our place in it.