The document provides information about several comets that have been observed throughout history including Comet McNaught, Comet Lovejoy, Comet Hyakutake, Comet Hale-Bopp, Comet Holmes, Comet Pan-STARRS, and Comet Lemmon. It includes details about the apparent magnitude, year of observation, and credit for images of each comet. The document also discusses comet classification in ancient Chinese texts, provides examples of notable comets throughout history like Halley's Comet and Comet Shoemaker-Levy 9, and summarizes models of comet composition and structure like the dirty snowball model.
17. The Great Comet of 1577
• No parallax
observed
• at least 230 times
Earth radius away
• Coma > 1/4 Earth
diameter
• Tail million km
第谷 Tycho Brahe
The Uraniborg - "Castle of the Heavens"
33. This graph shows the number of comets with different orbital inclinations. All comets known as
of December 31, 1989 are included except those named SMM, SOHO, SOLWIND, and those
with a D/ designation.
34. Kuiper Belt 凱伯帶
~ 30-50 AU
Kuiper belt objects (KBOs)
Trans-Neptunian Objects (TNOs)
Credit: KAGAYA
60. Making a Comet 彗星餐單
Credit: NASA/JPL-Caltech/R. Hurt (SSC)
61. Complex
molecules in
space
Prof Kwok discovered
complex organic matter
with both aliphatic
(long-string) and
aromatic (ring) features
in the Universe
61
62. Cometary volatiles detected
in spectroscopic surveys.
Most listed species are
regarded as primary, except
for HNC, which is in large part
a product species. Others
may be both primary and
product in origin (e.g., H2CO,
CO). For each molecular
species, the number of
comets in which it has been
detected is shown on the right
margin, and the range of
values found among those
detections is shown as a color
bar (light green). The six
species designated “1” on the
right margin were detected
only in comet Hale-Bopp, the
brightest comet of the past
several decades.
69. Too close to the Sun - Sungrazer
ISON perihelion @ 2.7 Rsun
70.
71. The number of comets with different perihelion distances. It includes all comets known as of mid2008 except for those with perihelion distances exceeding 7.0 au, those named
SMM, SOHO, SOLWIND and STEREO and those with a D/ designation
77. Possible scenario
• Case 1: Disintegration well before perihelion
• Case 2: Destruction near perihelion
• Case 3: Survival
78. Comet Shoemaker-Levy 9 Impact with Jupiter
休梅克利維9號彗星撞擊木星
P Fragment
Q Fragment
30 Mar 94
11 Jul 94
17 May 94
20 Jul 94
Credit: Dr. Hal Weaver and T. Ed Smith (STScI), J.T. Trauger, R.W. Evans (JPL), and NASA
79. 07/23/94 08:08 UT
(5 days after G impact)
07/21/94 06:22 UT
(3 days after G impact,
1.3 days after L impact)
07/18/94 09:19 UT
(1.5 hours after G impact)
07/18/94 07:38 UT
(about 5 minutes after G impact)
Credit: R. Evans, J. Trauger, H. Hammel and the HST Comet Science Team and NASA
91. In scale 按比例
951 Gaspra
243 Ida/Dactyl
253 Mathilde
18.2 x 10.5 x 8.9 km
53.6 x 24.0 x 15.2 km
66 x 48 x 46 km
1991-10-29 Galileo Flyby
S-type Main-belt Asteroid
1993-08-28 Galileo Flyby
S-type Main Belt Asteroid
1997-06-27 NEAR Flyby
C-type Main Belt Asteroid
433 Eros
5535 Annefrank
25143 Itokawa
13 x 13 x 33 km
6.6 x 5.0 x 3.4 km
0.535 x 0.294 x 0.209 km
2000-02-14 NEAR Orbit Insertion
S-type NEA
2002-11-02 Stardust Flyby
Unknown type
2005-11-20 Hayabusa Landed
S-type NEA
99. • Comets are like cats, they have tails, and they
do precisely what they want – David Levy
• Might not be fascinated for naked eyes
• But still fascinated for science