Jumat, 30 Januari 2009

uranus

Uranus Astronomical symbol of Uranus
Uranus as seen by Voyager 2
Uranus, as seen by Voyager 2
Discovery
Discovered by William Herschel
Discovery date March 13, 1781
Designations
Adjective Uranian
Epoch J2000
Aphelion 3 004 419 704 km
20.083 305 26 AU
Perihelion 2 748 938 461 km
18.375 518 63 AU
Semi-major axis 2 876 679 082 km
19.229 411 95 AU
Eccentricity 0.044 405 586
Orbital period 30 799.095 days
84.323 326 yr
Synodic period 369.66 days[2]
Average orbital speed 6.81 km/s[2]
Mean anomaly 142.955 717°
Inclination 0.772 556°
6.48° to Sun's equator
Longitude of ascending node 73.989 821°
Argument of perihelion 96.541 318°
Satellites 27
Physical characteristics
Equatorial radius 25 559 ± 4 km
4.007 Earths[3][c]
Polar radius 24 973 ± 20 km
3.929 Earths[3][c]
Flattening 0.022 9 ± 0.000 8[b]
Surface area 8.115 6×109 km²[4][c]
15.91 Earths
Volume 6.833×1013 km³[2][c]
63.086 Earths
Mass (8.6810 ± 0.0013)×1025 kg
14.536 Earths[5]
GM=5 793 939 ± 13 km³/s²
Mean density 1.27 g/cm³[2][c]
Equatorial surface gravity 8.69 m/s²[2][c]
0.886 g
Escape velocity 21.3 km/s[2][c]
Sidereal rotation
period
0.718 33 day
17 h 14 min 24 s[3]
Equatorial rotation velocity 2.59 km/s
9,320 km/h
Axial tilt 97.77°[3]
North pole right ascension 17 h 9 min 15 s
257.311°[3]
North pole declination −15.175°[3]
Albedo 0.300 (bond)
0.51 (geom.)[2]
Surface temp.
1 bar level[7]
0.1 bar
(tropopause)[8]
min mean max

76 K
49 K 53 K 57 K
Apparent magnitude 5.9[6] to 5.32[2]
Angular diameter 3.3"–4.1"[2]
Atmosphere[8][9][10][d]
Scale height 27.7 km[2]
Composition (Below 1.3 bar)
83 ± 3% Hydrogen (H2)
15 ± 3% Helium
2.3% Methane
0.009%
(0.007–0.015%)
Hydrogen deuteride (HD)[11]
Ices:

Ammonia

water

ammonium hydrosulfide (NH4SH)

methane (CH4)

caelus

Caelus, also known as Coelus, was the Roman god of the sky, personified from the Latin word for "sky", caelum.[1] Caelus was later equated with the Greek god of the heavens, Uranus, who was vastly more important to the Greeks than Caelus was to the Romans.

In the Roman adaptation of Greek mythology, Caelus was, by marriage to Tellus (Greek: Gaia), the father of Saturn (Greek: Cronus), Ops (Greek: Rhea), Oceanus, and the other Titans, as well as the Gigantes. Alone, Caelus was the father of Venus (Greek: Aphrodite).

Caelus is often associated with the sign of the zodiac, Aquarius.

The Roman Caelus (or Caelum) is simply a translation of the Greek Uranus or Ouranos (Οὐρανός), not the name of a distinct national divinity. There is no evidence of the existence of a cult of Caelus, though the name occurs in dedicatory inscriptions, due to Oriental influences; the worship of the sky being closely connected with that of Mithras. Caelus is sometimes associated with Terra, represented in sculptural art as an old, bearded man holding a robe billowing over his head in the form of an arch, a conventional sign of deity.

[edit] Notes

  1. ^ This personification is indicated by the use of the masculine form caelus rather that the neuter, caelum

[edit] References

  • Grimal, Pierre (1986). The Dictionary of Classical Mythology (pp. 83–84). Oxford: Basil Blackwell. ISBN 0-631-13209-0.

caelus

Caelus, also known as Coelus, was the Roman god of the sky, personified from the Latin word for "sky", caelum.[1] Caelus was later equated with the Greek god of the heavens, Uranus, who was vastly more important to the Greeks than Caelus was to the Romans.

In the Roman adaptation of Greek mythology, Caelus was, by marriage to Tellus (Greek: Gaia), the father of Saturn (Greek: Cronus), Ops (Greek: Rhea), Oceanus, and the other Titans, as well as the Gigantes. Alone, Caelus was the father of Venus (Greek: Aphrodite).

Caelus is often associated with the sign of the zodiac, Aquarius.

The Roman Caelus (or Caelum) is simply a translation of the Greek Uranus or Ouranos (Οὐρανός), not the name of a distinct national divinity. There is no evidence of the existence of a cult of Caelus, though the name occurs in dedicatory inscriptions, due to Oriental influences; the worship of the sky being closely connected with that of Mithras. Caelus is sometimes associated with Terra, represented in sculptural art as an old, bearded man holding a robe billowing over his head in the form of an arch, a conventional sign of deity.

[edit] Notes

  1. ^ This personification is indicated by the use of the masculine form caelus rather that the neuter, caelum

[edit] References

  • Grimal, Pierre (1986). The Dictionary of Classical Mythology (pp. 83–84). Oxford: Basil Blackwell. ISBN 0-631-13209-0.