126

Asteroids and Comets 1044

Asteroids

Ida24350Galileo

111993(NASA)

127

1-8

General properties

100

100

1-81001000

2-8

0.750.200.05

2.23.33-8

5

Vista

0.05

128

2-8 Gaspra5300Galileo1991

Eros(Near Earth Asteroid Rendezvous) NEAR 2000Mathilde

2400NEAR1997(NASA)

129

3-82.23.3

Naming of asteroids

1 Ceres, 2 Pallas, 3 Juno, 433 Eros, 243 Idah, …

1000 Piazzia,

Gaussia1001

Orbits of asteroids

9.524

64 Asteroidal belt 2.2

3.3

3.36

Resonance points

0.15

130

Trans-Neptunian objects

2005

100

10002000

6.4141968

Trojan Groups

150200

1000250

Lagrange

124-8

4-8

600600

131

Families of asteroids

Measurement of Asteroid size

1)

0.75-

8Rsd

s

sin (s) = tan (s) = s (in radians)

3600 2 = 6.28 radians

1 radian = 2π

360= 57.3

0 = 3438’ = 206265”

1 radian ~ 200 000” =2x105

5-8

radianin d

Rstan(s)

102 d

Rs" 5

dsR

s

d

R

132

2)

3)

Occultation

Mass of asteroids

243

0.0005

Types of asteroids

1) C asteroids

2) S asteroids

3) M asteroids

4)

The origin of Asteroids

Accretion

133

Comets

330

2001 Q4 Kitt Peak0.92004(NASA)

General properties

134

1997Hale-Bop

1910

1985

2061

200Enck

3.3200

6-8

6-8

135

The structure

7-8

0.5 13

coma0.80

CO, CO2HCNH2COCH3OH

CO+, N2

+, CO2

+, CH

+

8-8

H, OH,O, NH, NH2

7-82002 V1

9-8

50

1986

136

8-8(NASA)

9

19949

71992

Roche

10-8

19939

2112

137

1908Tunguska

11-8

Future of a comets

9

Meteors, meteorites and meteoroids

0.930.06

0.01

12-8

30

200110020

300

2

meteoroid swarm

13-8

138

1-8

1-8

Quadrantid Jan 343 -740 Lyrid Apr 2148 1861 I (Thatcher)41510

Eta Aquarid May 459 Halley7620 Delta Aquarid Jul 3043 -3.620

Perseid Aug 1161 1862 III (Swift-Tuttle)10550 Draconid Oct 924 Giacobini-Zinner6.6500 Orionid Oct 2066 Halley7630

Taurid Nov 730 Encke3.310 Leonid Nov 1672 1866 I (Tuttle)3312

Geminid Dec 1337 Phaethon1.650

9-8Tempel 1Deep Impact2005

Wild 2’sStardust20045.5

(NASA)

T=350 K T=200 K

139

10-8(HST)

(ESA)

11-8Tunguska

140

12-8200110030

20

13-8

141

Origin of the solar system

400

110

1100

T Tauri

0.11

142

Are there other solar systems?

Summary

100

143

1)

2)

3)

4)

5)

6)

7)

8)

9)

10)

11)

12)

13)

14)

15)

16)