Lecture 14 Review
Object
Equatorial
Radius
(km)
Mass
(kg)
Rotation
Period
(d)
Orbital
Period
(d)
Primary
Distance
(103 km)
Orbital
Inclination
(degrees)
Sun
695,700
1.99(30)
256.4
Mercury
2439
3.30(23)
58.6
89
.387 AU
7.0
Venus
6052
4.87(24)
243R
225
.723 AU
Earth
6378
5.98(24)
1.0
365
1738
7.35(22)
S
3394
6.44(23)
Phobos
14 x 10
Deimos
8x6
Moon
Mars
Orbital
Eccentri
city
Escape
Velocity
(km/s)
Known or
Probable Surface
617
ionized gas
0.206
4.2
basaltic dust/rock
3.4
0.007
10.4
basalt/granite
1.00 AU
0.0
0.017
11.2
water/granite/soil
27
384
18-29
0.055
2.4
basaltic dust/rock
1.02
687
1.52 AU
1.8
0.093
5.0
basaltic dust/rock
9.6(15)
S
0.32
9.4
1.0
0.015
.011
carbonaceous soil
1.0(15)
S
1.26
23
2.8
0.001
.006
carbonaceous soil
3-6 y
2-3 AU
Asteroid Belt
Ceres
510
1.2(21)?
0.38
4.6 y
2.77 AU
10.6
0.08
0.6
carbonaceous soil
Vesta
275
2.4(20)?
0.22
3.6 y
2.36 AU
7.1
0.09
0.3
basaltic soil
Pallas
269
?
0.33
4.6 y
2.77 AU
34.8
0.24
0.3
meteoritic soil
countless other asteroids of smaller size
Jupiter
71,400
1.90(27)
0.41
11.9 y
5.20 AU
1.3
0.048
60
liquid hydrogen?
Io
1815
8.94(22)
S
1.77
422
0.0
0.000
2.6
sulfur compounds
Europa
1569
2.80(22)
S
3.55
671
0.5
0.000
2.0
H2O ice
Ganymede
2631
1.48(23)
S
7.16
1070
0.2
0.001
3.6
H20 ice, dust
Callisto
2400
1.08(23)
S
16.69
1883
0.2
0.008
2.4
dust, H20 ice
24 small moons made up of dust, rock, and ice inside and outside the 4 Galilean satellites plus a faint ring
Saturn
60,330
5.69(26)
0.43
29.5 y
9.54 AU
2.49
0.056
36
liquid hydrogen?
Titan
2575
1.3(23)
?
15.04
1222
0.3
0.03
2.7
ice, liq NH3 CH3
Mimas
196
3.8(19)
S
0.94
186
1.5
0.02
0.2
mostly H20 ice
Enceladus
251
8.4(19)
S
1.37
234
0.0
0.00
0.2
mostly H20 ice
Tethys
524
7.5(20)
S
1.89
295
1.1
0.00
0.4
mostly H20 ice
Dione
559
1.0(21)
S
2.74
377
0.0
0.00
0.5
mostly H20 ice
Rhea
764
2.5(21)
S
4.52
527
0.4
0.00
0.7
mostly H20 ice
Iapetus
718
1.9(21)
S
79.23
3560
14.7
0.03
0.6
ice and soil
28 small moons plus a major ring system; Titan is comparable in size to the terrestrial planets
Chiron
100?
?
0.25
50.7 y
13.7 AU
7.0
0.33
0.17
soil and ice
Uranus
25,400
8.76(25)
0.72 h
84.0 y
19.13 AU
0.8
0.05
21
rock, liq H2, He
Miranda
242
?(19)
S
1.41
130
3.4
0.02
0.4
H20, soil
Ariel
550
1.4(21)
S
2.52
192
0
0.00
0.7
H20, soil
Umbriel
595
1.2(21)
S
4.14
267
0
0.00
0.6
H20, soil
Titania
800
3.4(21)?
S
8.71
436
0
0.00
1.1
H20, soil
Oberon
775
2.9(21)
S
13.45
586
0
0.00
1.0
H20, soil
10 small moons plus faint rings
Neptune
Triton
24,300
1.03(26)
0.67
184.8 y
30.07 AU
1.8
0.01
24
rock, liq H2, He
1353
2.1(22)
S
5.88
354
159R
0.00
2.6
CH3, ice
7 small moons plus faint dark rings
Pluto
1150
1.5(22)
6.4
247.7 y
39.4 AU
17.2
0.25
0.9
CH3, ice
Charon
600
2.0(21)?
S
6.39
19.6
0?
0?
?
CH3, ice
Kuiper Belt 50-500 AU in ecliptic plane; Öort Cloud 500-50,000 Au in spherical shell
Solar System Characteristics to be Explained by a Theory of Origin
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
All the planets’ orbits lie roughly in a single plane.
The Sun’s rotational equator lies nearly in this plane.
Planetary orbits are nearly circular.
The planets and the Sun all revolve in the same west-to-east direction, called
prograde (or direct) revolution.
Planets differ in composition.
The composition of planets varies roughly with distance from the Sun: Dense,
metal-rich planets lie in the inner system.
Meteorites differ in chemical and geological properties from all known planetary
and lunar rocks.
The Sun and all the planets except Venus and Uranus rotate on their axis in the
same direction (prograde rotation). Obliquity (tilt between equatorial and orbital
planes is generally small.
Planets and asteroids rotate with rather similar periods, about 5 to 10 hours,
unless obvious tidal forces allow them (as in Earth’s case).
Distances between planets usually obey the simple Bode’s rule.
Planet-satellite systems resemble the solar system.
As a group, most comet’s orbits define a large, almost spherical swarm around
the solar system (the Ort cloud). Other comets reside in the Kuiper belt, near
Pluto and just beyond it.
The planets have much more angular momentum (a measure relating orbital
speed, size, and mass) than the Sun. (Failure ot explain this was the great flaw of
the early evolutionary theories.)
Masses
Sun
Jupiter
Saturn
Uranus
Neptune
Earth
Venus
Mars
Mercury
Pluto
2(30)
2(27)
6(26)
9(25)
1(26)
6(24)
5(24)
6(23)
3(23)
1.5(22)