Uranus

Uranus was identified as a planet by William Herschel in 1781. It is the third giant planet outward from the Sun, roughly half Saturn's diameter and close to Neptune in size and mass.

Its small greenish disk is bright enough to sit near the limit of naked-eye visibility. That is why Uranus appeared on star charts before its planetary nature was recognized; John Flamsteed recorded it as a star in Taurus. Even in larger amateur telescopes, Uranus usually shows little more than a tiny disk without obvious belts or storms.

Physical Data
Uranus
Mass ratio Sun/planet
22'962
Mass of planet
86.625000 1024 kg
Equator radius
25559 km
Rotation period
-0.71833 days
Flattening
0.022927
Density
1.3 kg/dm3
Visual magnitude at 1 AU
-7.19 mag
Albedo
0.51
Northpole RA
10h43.4m
Northpole DE
-15.09°
Orbit Data
Uranus
Revolution period
84 years 8 days
Sun radiation power
3.4 to 4.1 W/m2
Distance from Sun (min)
2735 Mio km
Distance from Sun (max)
3005 Mio km
Distance from Earth (min)
2590 Mio km
Distance from Earth (max)
3160 Mio km
Orbital Elements*
Uranus
Inclination
0.77271°
Longitude of node
74.0466°
Longitude of perihel
174.63°
Semi-major axis
19.24855 AU
Daily motion
0.01167123°/day
Eccentricity
0.0469442

*) Epoche 8 January 1994, 0h UT, Equ. J2000