The Solar System

608 APPENDIX A

■ Table A-9 ❙ The 15 Nearest Stars

Name

Absolute

Magnitude

(Mv)

Distance

(ly)

Spectral

Type

Apparent Visual

Magnitude

(mv)

Sun

Proxima Cen

Cen A

Cen B

Barnard’s Star

Wolf 359

Lalande 21185

Sirius A

Sirius B

Luyten 726-8A

Luyten 726-8B (UV Cet)

Ross 154

Ross 248

 Eri

Luyten 789-6

4.83

15.45

4.38

5.76

13.21

16.80

10.42

1.41

11.54

15.27

15.8

13.3

14.8

6.13

14.6

4.28

4.3

4.3

5.9

7.6

8.1

8.6

8.6

8.9

8.9

9.4

10.3

10.7

10.8

G2

M5

G2

K5

M5

M6

M2

A1

white dwarf

M5

M6

M5

M6

K2

M7

26.8

11.05

0.1

1.5

9.5

13.5

7.5

1.5

7.2

12.5

13.0

10.6

12.2

3.7

12.2

608 APPENDIX A

■ Table A-10 ❙ Properties of the Planets

Physical Properties (Earth  ⊕)

Planet

Equatorial Radius

Mass

(⊕  1)

Average

Density

(g/cm^3 )

Surface

Gravity

(⊕  1)

Escape

Velocity

(km/s)

Sidereal

Period of

Rotation

Inclination

of Equator

(km) (⊕  1) to Orbit

Mercury

Venus

Earth

Mars

Jupiter

Saturn

Uranus

Neptune

2439

6052

6378

3396

71,494

60,330

25,559

24,750

0.38

0.95

1.00

0.53

11.20

9.42

4.01

3.93

0.056

0.815

1.000

0.108

317.8

95.2

14.5

17.2

5.44

5.24

5.50

3.94

1.34

0.69

1.19

1.66

0.38

0.90

1.00

0.38

2.54

1.16

0.92

1.19

4.3

10.3

11.2

5.0

61

35.6

22

25

58.65d

243.02d

23.93h

24.62h

9.92h

10.23h

17.23h

16.05h

0°

177°

23°.5

25°.3

3°.1

26°.4

97°.9

28°.8

Orbital Properties

Planet

Average

Orbital

Velocity

(km/s)

Orbital

Eccentricity

Inclination

to Ecliptic

Semimajor Axis (a) Orbital Period (P)

(AU) (10^6 km) (y) (days)

Mercury

Venus

Earth

Mars

Jupiter

Saturn

Uranus

Neptune

0.39

0.72

1.00

1.52

5.20

9.54

19.18

30.06

57.9

108.2

149.6

227.9

778.3

1427.0

2869.0

4497.1

0.24

0.62

1.00

1.88

11.87

29.46

84.01

164.79

87.97

224.68

365.26

686.95

4334.3

10,760

30,685

60,189

47.89

35.03

29.79

24.13

13.06

9.64

6.81

5.43

0.206

0.007

0.017

0.093

0.048

0.056

0.046

0.010

7°.0

3°.4

0° *

1°.9

1°.3

2°.5

0°.8

1°.8

* By defi nition.