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© by Zane B. Stein

SIZE, ORBIT, DISCOVERY DEGREES & MORE

SIZE

To put things in perspective, here is a list of the relative diameters of most of the Centaurs, to the best of our knowledge. These sizes may change somewhat, as more accurate measurements are taken:

ESTIMATED SIZES


CENTAUR	DIAMETER 
             IN KM
1995 SN55	278
Chariklo	270
2002 GZ32	192
Pholus  	187
Chiron  	163
Bienor  	133
Amycus  	121
Hylonome	111
2002 FY36	92
2003 UW292	92
#121725 (1999 XX143)	84
2002 PQ152	84
2002 QX47	84
2003 QC112	80
#120061 	73
Thereus 	70
Crantor  	67
Asbolus 	66
1996 PX33	61
Cyllarus	61
Echeclus	55
2001 KF77	55
Nessus  	53
#119315 	51
Elatus  	47
#250112 (2002 KY14)	46
2000 C0104	42
2002 DH5	40
2003 UY292	40
1999 JV127	37
Pelion	       37
2003 UA118	30
2000 SN331	29
119976   	29
2003 QD112	29
2001 XZ255	27
2002 VG131	25
Okyrhoe  	24
2000 FZF3	23
1994 TA	22
2001 BL41	20
2002 CA249	18
2003 LH7	14
2003 QP112	13
1999 HD12	12
2003 QN112	12
2002 TK301	9
1996 AR20	7
2004 CJ39	7
2000 GM137	6

  

1995 SN55 is the largest Centaur so far, and the centaur with the highest eccentricity of all. And it is the brightest, as well, brighter than either Chiron or Chariklo. Most likely this means it will be huge.

DISCOVERIES

There are two different 'discovery dates' for each Centaur, although sometimes they are only minutes or hours apart. The first is the moment a photographic plate was taken of the body. The second is the moment the astronomer, while looking at the plate, first becomes aware that a new body has been sighted.

We have the exact times for both of the above only for Chiron and Pholus. For all the other Centaurs, the astronomers either don't remember exactly when they looked at the plates, or haven't responded to any enquiries on the subject.

When the actual 'human' discovery of a body is known, this is the most important discovery chart.

For Chiron, we have a letter from discover Charles Kowal giving "around 10 am" on November 1, 1977 as the discovery moment. So the discovery position of 3 Taurus 08 is most often quoted, and what I use throughout this website. (The photographic plates had been taken Oct. 18-19 that year.)

In response to a letter to David Rabinowitz, discoverer of Pholus, I received the following reply in 1994:

"Dear Mr. Stein,
You wrote to me asking about 1992 AD, which has since been named (5145) Pholus.
I discovered it 1992 Jan. 9 at 9:01 Universal time, about 2:01 in the morning at Kitt Peak in Arizona.
Sincerely,
David Rabinowitz"

Again, I use that discovery position whenever I refer to Pholus.

For all of the other Centaurs, though, the 'human' discovery moment is not known. Thus the tables below contains the photographic plates' discovery positions.

In some cases, the photographic plate was looked at only hours after it was shot. In those cases the discovery degree is virtually identical in both charts. Take for example these letters which I received from Jim Scotti, discoverer of Asbolus and Chariklo:

"Hi Zane,
Thanks for your interest in our objects. (8405) Asbolus (=1995 GO) was found by me on April 5, 1995 (the observation time was 09:26:20 UT). (10199) Chariklo (=1997 CU26) was found by me on February 15, 1997 (the observation time was 02:51:16 UT). I found them using our 36 inch Spacewatch telescope on Kitt Peak. We use a CCD camera to survey the solar system and reduce the data with automated software.
Jim."
As I read this, it sounded as though the time he listed was the time the photographs were taken, so I wrote back and questioned that, and asked if he remembered when he first verified the actual bodies....the actual moment of human discovery. His response:

"Hi, Zane,
Those are the actual mid-time of exposure. We take 3 electronic images of the sky and compare them digitally, so the object would have been recognized by the software about an hour later and confirmed the following afternoon by visual examination of the images.
Jim"

So, it appears that Asbolus was 'discovered' by Jim on the afternoon of April 6, 1995, while Chariklo was 'discovered' on the afternoon of February 16, 1997. As you can see by looking at the ephemeris, neither body moved much at all in one day, and so the discovery degrees, below, are virtually identical.

A third 'discovery date' has been proposed by at least one person....the moment that the Centaur's is officially announced to the world. However, I feel that utilizing that chart would be like using a chart for the moment the new parents mail out birth announcements to their friends.

Perhaps we can look at the discovery plates as the 'conception', and the human discovery moments as the 'birth' of each Centaur into humanity's awareness?

Here is a table of discovery dates, including the position of each Centaur at its discovery:

BODY DISCOVERY
DATE
DISCOVERY
POSITION
ORBIT
Chiron (2060) November 1, 1977 3 Tau 08 50.5 yrs
Pholus (5145) January 9, 1992 0 Leo 36 92.3 yrs
Nessus (7066) April 26, 1993 4 Sco 49 121 yrs
1994 TA (Pylenor) October 2, 1994 18 Ari 31 68.4 yrs
Hylonome (10370) February 27, 1995 4 Lib 42 127 yrs
Asbolus (8405) April 5, 1995 7 Lib 46 76.2 yrs
1995 SN55 September 20, 1995 14 Ari 16 114 yrs
1996 AR20 January 12, 1996 4 Leo 02 59.2 yrs
1996 AS20 January 14, 1996 19 Leo 23 214 yrs
1996 RX33 September 8, 1996 15 Pis 33 117 yrs
Chariklo (10199) February 15, 1997 6 Leo 03 63.2 yrs
#33128 (1998 BU48) January 22, 1998 13 Leo 10 193 yrs
Pelion (49036) August 21, 1998 9 Aqu 59 89.2 yrs
Okyrhoe (52872) September 19, 1998 24 Pis 35 24.3 yrs
Cyllarus (52975) October 12, 1998 18 Tau 34 133 yrs
1999 HD12 April 17, 1999 7 Lib 44 98.5 yrs
1999 JV127 May 10, 1999 1 Lib 04 68.4 yrs
#44594 (1999 OX3) July 21, 1999 2 Aqu 41 182 yrs
Elatus (31824) October 29, 1999 5 Tau 13 40.4 yrs
#121725 (1999 XX143) December 13, 1999 26 Can 44 76.1 yrs
2000 CO104 February 5, 2000 26 Leo 50 110 yrs
Echeclus (60558) March 3, 2000 16 Virgo 54 35.3 yrs
2000 FZ53 March 31, 2000 26 Lib 57 117 yrs
2000 GM137 April 2, 2000 22 Vir 20 21.9 yrs
#87555 (2000 QB243) August 25, 2000 9 Aqu 24 207 yrs
Bienor (54598) August 27, 2000 3 Pis 30 66.8 yrs
2000 SN331 September 23, 2000 0 Gem 20 87.09 yrs
#63252 (2001 BL41) January 21, 2001 24 Can 36 30.5 yrs
#88269 (2001 KF77) May 22, 2001 2 Sco 45 134 yrs
Thereus (32532) August 9, 2001 20 Sco 52 34.6 yrs
#119315 (2001 SQ73) September 19, 2001 20 Ari 01 72.7 yrs
2001 XA255 December 9, 2001 15 Can 48 166 yrs
2001 XZ255 December 11, 2001 14 Can 13 63.8 yrs
2002 CA249 February 6, 2002 15 Leo 51 94.3 yrs
2002 CB249 February 7, 2002 13 Vir 44 152 yrs
2002 DH5 February 20, 2002 3 Vir 54 104 yrs
2002 FY36 March 18, 2002 16 Vir 35 156 yrs
Amycus (55576) April 8, 2002 7 Lib 11 127 yrs
Crantor (83982) April 12, 2002 7 Sco 26 86.3 yrs
#95626 (2002 GZ32) April 13, 2002 0 Lib 48 112 yrs
#250112 (2002 KY14) May 19, 2002 13 Sag 23 45.4 yrs
#73480 (2002 PN34) August 6, 2002 3 Aqu 17 171 yrs
2002 PQ152 August 12, 2002 8 Pis 34 130 yrs
2002 QX47 August 26, 2002 22 Aqu 32 82.3 yrs
2002 TK301 October 6, 2002 0 Tau 47 64.6 yrs
#119976 (2002 VR130) November 7, 2002 19 Ari 12 111 yrs
2002 VG131 November 9, 2002 17 Ari 21 73.1 yrs
#120061 (2003 CO1) February 2, 2003 4 Vir 43 95.9 yrs
2003 KQ20 May 30, 2003 10 Sag 04 34.3 yrs
2003 LH7 June 1, 2003 8 Sag 46 69.9 yrs
2003 QC112 August 24, 2003 14 Pis 38 104 yrs
2003 QD112 August 26, 2003 27 Pis 43 82.4 yrs
2003 QN112* August 29, 2003 1 Pis 02 126 yrs
2003 QP112 August 29, 2003 1 Pis 09 97.1 yrs
2003 UW292 October 23, 2003 4 Tau 10 77.1 yrs
2003 UY292 October 23, 2003 23 Tau 23 102 yrs
2003 UA118 October 27, 2003 19 Ari 32 41.0 yrs
2003 WL7 November 16, 2003 12 Ari 57 133 yrs
2004 CJ39 February 14, 2004 5 Leo 58 46.7 yrs

*Note: The MPC (Minor Planet Center) has decided, for now, that the definition of Centaurs is a body which has its perihelion outside of Jupiter and semimajor axis inside of Neptune. So by that definition, some of the above bodies may not be Centaurs.

Juan Revilla has coined the names "Quasi-Centaurs" and "Pluto Steeds" to categorize those Centaur-like bodies that fit outside of the MPC's definition. These include #33128 (1998 BU48), #44594 (1999 OX3), #87555 (2000 QB243), 2001 XA255, and #73480 (2002 PN34).

Of special interest is the relationship that Elatus has with Chiron. Discovered in the 6th degree of Taurus (5 Taurus 13), its Sabian Symbol is "A bridge being built across a gorge." Chiron's Symbol has been described as a bridge linking the earthly with the celestial. Both bodies were discovered when the Sun was in Scorpio, in virtually the same part of that sign, giving another connection.

In the years 1955 and 1956, Chiron, Pholus, Heracles and Damocles were all very close together, in the first decanate of Aquarius. What did this mean for the world? What does it mean for people born at this time? And what does it mean that Uranus recently transited the following points? What are your thoughts on the matter?

Jan. 26, 1955, Damocles conjunct Pholus 4 Aquarius 34.
Jan. 30, 1955, Chiron conjunct Heracles 0 Aquarius 12.
Feb. 5, 1955, Pholus conjunct Heracles 4 Aquarius 54.
Feb. 6, 1955, Damocles conjunct Heracles 5 Aquarius 29.
Jan. 12, 1956, Damocles conjunct Pholus 5 Aquarius 18.
Jan. 24, 1956, Chiron conjunct Pholus 5 Aquarius 43.

Here are a few of my thoughts. During this period, the United States and Mainland China came perilously close to war over Nationalist China. Nikita Kruschev emerged as 'the' power in Russia, and declared his famous "We will bury you." Rosa Parks, in December 1954, refused to be moved, insisted on sitting in the front of a bus, and made history. On the other hand, the governors of Virginia, Georgia, Mississippi and South Carolina united to try to fight the integration of schools. The first atomic submarine was launched. IBM ended its 4-year antitrust suit and agreed to license patents and to SELL rather than rent computers. (Oh, and Proctor & Gamble first introduced Comet to the world!)

ORBITS

A lot can be understood about a Centaur by looking at its Perihelion (closest approach to the Sun) and Aphelion (furthest distance from the Sun), and by comparing these to the orbits of the major planets, and other bodies like the Trans-Plutonians. Here is that information, sorted by Perihelion. Perihelion and Aphelion are measured in AU. If it is not a Centaur, it will have one of the following codes next to the name: (M) = Minor Planet, (P) = Planet, (T) Trans-Plutonian.

BODY PERIHELION APHELION ORBIT
MARS (P) 1.41 1.64 1.88 yrs
DAMOCLES (M) 1.5769 22.1028 40.71 yrs
JUPITER (P) 5.03 5.37 11.86 yrs
1996 AR20 5.68 25.99 59.2 yrs
Okyrhoe (52872) 5.8001 10.9806 24.3 yrs
Echeclus (60558) 5.8639 15.6718 35.3 yrs
2004 CJ39 6.72 19.2 46.7 yrs
Asbolus (8405) 6.8333 29.1 76.2 yrs
#63252 (2001 BL41) 6.905 12.638 30.5 yrs
2000 GM137 6.9337 8.861 21.9 yrs
Elatus (31824) 7.2663 16.3063 40.4 yrs
1995 SN55 7.41 223.5 114 yrs
2003 UA118* 7.55 54.42 41.0 yrs
1999 HD12 8.26 46.09 98.5 yrs
Chiron (2060) 8.4568 18.9034 50.5 yrs
2003 KQ20 8.5 12.8 34.3 yrs
Thereus (32532) 8.5122 12.7183 34.6 yrs
Pholus (5145) 8.7316 32.1297 92.3 yrs
SATURN (P) 9.2 9.96 29.46 yrs
2001 XA255 9.38 51.08 166 yrs
#121725 (1999 XX143) 9.67 26.2495 76.1 yrs
#120061 (2003 CO1) 10.93 30.98 95.9 yrs
#250112 (2002 KY14) 11.02 13.56 45.4 yrs
1994 TA (Pylenor) 11.6711 21.7891 68.4 yrs
Nessus (7066) 11.8009 37.4072 121 yrs
#29981 (1999 TD10) (T) 12.281 177.813 927 yrs
2003 LH7 12.3 18.42 69.9 yrs
2000 FZ53 12.42 35.3588 117 yrs
2002 CA249 12.47 31.62 94.3 yrs
Chariklo (10199) 13.0775 18.658 63.2 yrs
Bienor (54598) 13.1525 19.7818 66.8 yrs
#73480 (2002 PN34) 13.3267 48.4816 172 yrs
2002 CB249 13.8 42 152 yrs
2002 TK301 13.97 18.13 64.6 yrs
2002 DH5 13.994 30.3575 104 yrs
Crantor (83982) 14.0458 25.0133 86.3 yrs
2003 QP112 14.21 27.88 97.1 yrs
#119315 (2001 SQ73) 14.3616 20.4527 72.7 yrs
2002 VG131 14.87 19.94 73.1 yrs
#119976 (2002 VR130) 14.91 31.69 111 yrs
2003 QN112 15.01 47.26 126 yrs
2003 WL7 15.04 24.29 133 yrs
Amycus (55576) 15.1935 35.3432 127 yrs
#87555 (2000 QB243) 15.2196 54.5892 207 yrs
2001 XZ255 15.4403 16.4903 63.8 yrs
1999 JV127 15.46 20.97 68.4 yrs
1996 AS20 15.69 32.11 214 yrs
2003 UW292 15.86 20.48 77.1 yrs
2003 UY292 15.9 27.93 102 yrs
Cyllarus (52975) 16.2502 35.9635 133 yrs
Pelion (49036) 17.2417 22.6758 89.2 yrs
2003 QC112 17.36 26.76 104 yrs
#44594 (1999 OX3) 17.5923 46.6602 182 yrs
2002 QX47 18.05 18.17 82.3 yrs
#95626 (2002 GZ32) 18.0611 28.3582 112 yrs
URANUS (P) 18.64 19.75 84.01 yrs
1996 RX33 18.67 33.56 117 yrs
2000 SN331 18.81 20.48 87.09 yrs
Hylonome (10370) 18.8844 31.504 127 yrs
#88269 (2001 KF77) 19.8268 32.436 134 yrs
2002 PQ152 20.59 30.63 130 yrs
#33128 (1998 BU48) 20.6015 46.1508 193 yrs
2000 CO104 20.6088 27.8605 119 yrs
2002 FY36 25.66 32.43 156 yrs
Huya (38628) (T) 28.5507 50.9701 251 yrs
PLUTO (P) 29.73 49.5 247.7 yrs
NEPTUNE (P) 29.76 30.3 164.8 yrs
2003 QD112 29.95 82.44 82.4 yrs
Ixion (28978) (T) 30.0546 49.1574 240 yrs
Orcus (90482) (T) 30.7527 48.054 247 yrs
Rhadamanthus (38083)(T) 33.2148 45.2203 246 yrs
15874 (1996 TL66) (T) 35.0276 130.69 753 yrs
ERIS (136199) (T) 37.77 97.56 557 yrs
19308 (1996 TO66) (T) 37.9012 48.4033 284 yrs
Varuna (20000) (T) 40.7719 45.1886 282 yrs
15760 (1992 QB1) (T) 40.8722 46.6077 289 yrs
Chaos (19521) (T) 40.9277 50.331 308 yrs
Deucalion (53311) (T) 41.5676 47.1761 296 yrs
Quaoar (5000) (T) 41.99 45.0543 285.68 yrs
Sedna (90377) (T) 76.0332 913.544 10,706 yrs

***************

CENTAURS & SABIAN SYMBOLS

The degree a planet is in at its discovery seems to become a highly sensitive degree from that point on. For example, Uranus was found in the 25th degree of Gemini, and there has been something Uranian about that degree ever since.

The Sabian Symbols.....a system of abstract images, one for each of the 360 degrees of the zodiac.....is a powerful tool for understanding the nature of the 'coming into our awareness' of the newly discovered body. While there are other degree-symbol systems, this is the one that I find the most powerful. Originally derived by teamwork between Marc E Jones and a psychic, and further expounded upon by Dane Rudhyar, they have been given even more momentum in a book entitled "The Sabian Symbols as an Oracle" by Lynda Hill and Richard Hill. Click on the link to find out more on the book. Or, even better, jump to Lynda and Richard's website, http://www.sabiansymbols.com. Find out much more about the Sabian Symbols there. And there, you can also look up the Sabian symbol for any degree, including the interpretive text!

Here follows a list of the Centaur discovery degrees, and the symbols from the above book. When you meditate upon them, perhaps a flash of lightning will light up your consciousness.

2003 WL7 Aries 13 A bomb which failed to explode is now safely concealed
1995 SN55 Aries 15 An Indian weaving a blanket
2002 VG131 Aries 18 An empty hammock is hanging between two lovely trees.
1994 TA Aries 19 A magic carpet of oriental imagry
Eris (136199) & #119976 (2002 VR130) & UA118 Aries 20 A young girl feeding swans in a park on a wintry day.
#119315 (2001 SQ73) Aries 21 A pugilist entering the ring
2002 TK301 Taurus 1 A clear mountain stream flows through a rocky defile.
CHIRON
& #15874
conjunct star Sharatan
Taurus 4 A pot of gold at the end of the rainbow
2003 UW292 Taurus 5 A young widow, tranfigured by grief, kneels at a grave.
Elatus (31824) Taurus 6 A bridge being built across a gorge
Sedna Taurus 18 A woman is airing a linen bag through a sunny window
Cyllarus (52975)
conjunct star Epsilon Eridani
Taurus 19 A new continent rising out of the ocean
2003 UY292 Taurus 24 Indian, human scalps hanging at his belt, rides proudly.
Chaos Taurus 27 An old Indian woman selling beads and trinkets.
2000 SN331 Gemini 1 A glass-bottomed boat reveals undersea wonders
Varuna Cancer 11 A clown caricatures merrily all kinds of human traits
2001 XZ255 Cancer 15 A group of people who have overeaten and enjoyed it
2001 XA255 Cancer 16 A man studying a mandala in front of him, with the help of a very ancient book
#63252 (2001 BL41) Cancer 25 A leader of men wrapped in an invisible mantle of power
#121725 (1999 XX143) Cancer 27 A violent storm in a canyon filled with expensive homes
PHOLUS Leo 1 Under emotional stress, blood rushes to a man's head
1996 AR20 & TYPHON Leo 5 Rock formations tower over a deep canyon
2004 CJ39 Leo 6 An old-fashioned 'conservative' woman is confronted by an up-to-date girl
CHARIKLO Leo 7 The constellations of stars in the sky
#33128 (1998 BU48) Leo 14 Cherub-like, a human soul whispers, seeking to manifest
2002 CA249 Leo 16 Brilliant sunshine just after a storm
1996 AR20 Leo 20 American Indians performa a ritual to the Sun
Orcus Leo 25 A man, alone, daringly crosses the desert on camelback
2000 CO104 Leo 27 Daybreak ďż˝ The luminescence of dawn in the eastern sky
2002 DH5 Virgo 4 Black and white children playing happily together
#120061 (2003 CO1) Virgo 5 Irishman dreams of "little people" beneath a tree.
2002 CB249 Virgo 14 A family tree
Echeclus (60558)
2002 FY36
Virgo 17 A volcanic eruption
2000 GM137 Virgo 23 A lion-tamer rushes fearlessly into the circus arena
2002 GZ32 Libra 1 A butterfly preserved and made perfect with a dart through it
1999 JV127 & Rhadomanthus Libra 2 A symphony is played dramatizing man's heroic ascent.
Hylonome Libra 5 A man teaching the true inner knowledge of the new
world to his students
ASBOLUS
1999 HD12
Amycus (55576)
Libra 8 A blazing fireplace in a deserted home
Huya Libra 19 Robbers are hiding, ready to attack heavily armed caravan
Deucalion Libra 25 Falling golden leaf teaches life to rebellious schoolboy
2000 FZ53 Libra 27 An airplane sails, high in the clear sky
2001 KF77 Scorpio 3 Neighbors help in a house-raising party in a small village
NESSUS Scorpio 5 A massive, rocky shore resists the pounding of the sea
Crantor (83982) Scorpio 8 The moon shining across a lake
Thereus (32532) Scorpio 21 Soldier ready to face charges of desertion for love's sake
(28978) Ixion (a TNO) Sagittarius 6 A cricket game is being watched by a colorful crowd
2003 LH7 Sagittarius 9 A mother is leading her children up a broad stairway
2003 KQ20 & Quaoar Sagittarius 11 An ever-burning lamp throws light upon an archaic idol.
#250112 (2002 KY14) Sagittarius 14 Sphinx and Pyramids stand, remains of a glorious past.
#44594 (1999 OX3) Aquarius 3 A deserter suddenly realizes the fallacy of his conduct
#73480 (2002 PN34) Aquarius 4 A Hindu pundit reveals himself suddenly a great healer.
Pelion (#49036)
Bienor (#87555)
Aquarius 10 A popularity that proves to be fleeting
2002 QX47 Aquarius 23 A big trained bear performs, sitting on a huge chair.
2003 QN112 & 2003 QP112 Pisces 2 Squirrel, showing human acumen, hides from hunter.
Bienor (54598) Pisces 4 Heavy traffic on a narrow isthmus linking two seaside resorts
2002 PQ152 Pisces 9 The race begins: intent on outdistancing his rivals, a jockey spurs his horse to great speed
2003 QC112 Pisces 15 An officer in unkempt campaign uniform drills his men.
1996 RX33 Pisces 16 In a quiet museum, an art student drinks in inspiration
Okyrhoe(52872)
conjunct star 51 Pegasi
Pisces 25 The purging of the priesthood
2003 QD112 Pisces 28 Under the full moon the fields seem strangely alive.

NOTE: The symbols for some of the Centaurs in this chart were designed by Sandy Turnbull.

MINI EPHEMERIDES FOR CHIRON AND THE OTHER CENTAURS

Jump to the Ephemeris Page.

THE OUTER SOLAR SYSTEM

If you would like to see a chart of the outer solar system that includes Chiron, Pholus, Damocles, and many other bodies, jump to this Outer Plot Chart

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