Transcript Planet Uranus

A Blue-Green World
Uranus is the third largest
planet after Jupiter and
Saturn. Uranus has 21 moons
and small, dusty rings.
Voyager 2 acquired this view
of the seventh planet while
departing the Uranian system
in late January 1986. This
image looks at the planet
approximately along its
rotational pole.
Voyager 2 image of Uranus, 1986 (Image:NASA)
A Blue-Green World
Uranus has a thick hydrogenmethane atmosphere. Methane
causes the planet’s blue-green
color.
Some astronomers call Uranus and
Neptune ‘ice giants’ because most
of their mass is ice and some rocky
material.
It appears that Uranus does not
have a rocky core like Jupiter and
Saturn but rather that its material is
more or less uniformly distributed.
Hubble’s View
This image, taken by Hubble,
clearly shows Uranus and its
rings.
Uranus’ rings are smaller and
dustier than those of Saturn,
and will eventually dissipate.
Image: NASA
Deep exposure of Uranus taken
with the Hubble Space
Telescope reveal two small
moons and two faint rings. All
orbit outside of Uranus's
previously known (main) ring
system, but interior to the large,
classical moons.
Dusty Rings
This image reveals many broad
lanes of dust surrounding the 9
main rings of Uranus. It was
taken by Voyager 2 looking
back toward the sun through
the ring system.
Tipsy?
Uranus moves around the Sun
with its rotation axis is
perpendicular to its orbit
around the sun.
It is thought that a planet-sized
body hit Uranus early in its
history, “tipping” it over.
Because of this, Uranus’
seasons last over 20 years!
Earth
Uranus
Distance from Sun
1.7 Billion Miles
93 Million Miles
Diameter
32,000 Miles
7926 Miles
Length of Year
84 Earth Years
365.25 Days
Length of Day
17.24 hours
23 hours 56 minutes
Gravity
.89 that of Earth
2.66 times that of Mars
Temperature
Average -319 degrees F Average 57 degrees F
Number of Moons
27
1
George’s Star
• Uranus was discovered by
William Herschel, the British
royal astronomer, in 1781.
• Herschel thought the planet
was a comet at first!
• He tried to name it
“George’s Star” after King
George.
God of the Sky
The name "Uranus" was eventually
proposed in order to conform with
the other planetary names from
classical mythology. The name
didn't come into common use until
1850.
To the ancient Greeks, Uranus was
god of the sky and heavens.
Missions
Only one spacecraft has visited
Uranus. On Jan. 24, 1986
Voyager 2 passed within 50,600
miles.
Voyager 2 radioed images and
scientific data on the planet, its
moons, rings, atmosphere,
interior and the magnetic
environment surrounding
Uranus.
Uranus’ Moons
Miranda
Ariel
Umbriel
Titania
Oberon
Uranus has 5 medium-sized moons and 21 smaller moons.
The five main satellites are Miranda, Ariel, Umbriel, Tatania and Oberon.
Miranda
Uranus’ moon Miranda has
a strange fractured
appearance, as if it was
shattered then put back
together.
The high cliffs and winding
valleys of the moon may
indicate that Miranda was
larger in the past and shrank
to its current size.
Titania
Picture of Titania
taken by Voyager 2.
Titania is 1600
kilometers in
diameter.
An artists view,
this montage of
images of the
Uranian system
was prepared
from an
assemblage of
images taken by
the Voyager 2
spacecraft
during its Uranus
encounter in
January 1986.